--- /dev/null
+// stb_voxel_render.h - v0.84 - Sean Barrett, 2015 - public domain
+//
+// This library helps render large-scale "voxel" worlds for games,
+// in this case, one with blocks that can have textures and that
+// can also be a few shapes other than cubes.
+//
+// Video introduction:
+// http://www.youtube.com/watch?v=2vnTtiLrV1w
+//
+// Minecraft-viewer sample app (not very simple though):
+// http://github.com/nothings/stb/tree/master/tests/caveview
+//
+// It works by creating triangle meshes. The library includes
+//
+// - converter from dense 3D arrays of block info to vertex mesh
+// - shader for the vertex mesh
+// - assistance in setting up shader state
+//
+// For portability, none of the library code actually accesses
+// the 3D graphics API. (At the moment, it's not actually portable
+// since the shaders are GLSL only, but patches are welcome.)
+//
+// You have to do all the caching and tracking of vertex buffers
+// yourself. However, you could also try making a game with
+// a small enough world that it's fully loaded rather than
+// streaming. Currently the preferred vertex format is 20 bytes
+// per quad. There are plans to allow much more compact formats
+// with a slight reduction in shader features.
+//
+//
+// USAGE
+//
+// #define the symbol STB_VOXEL_RENDER_IMPLEMENTATION in *one*
+// C/C++ file before the #include of this file; the implementation
+// will be generated in that file.
+//
+// If you define the symbols STB_VOXEL_RENDER_STATIC, then the
+// implementation will be private to that file.
+//
+//
+// FEATURES
+//
+// - you can choose textured blocks with the features below,
+// or colored voxels with 2^24 colors and no textures.
+//
+// - voxels are mostly just cubes, but there's support for
+// half-height cubes and diagonal slopes, half-height
+// diagonals, and even odder shapes especially for doing
+// more-continuous "ground".
+//
+// - texture coordinates are projections along one of the major
+// axes, with the per-texture scaling.
+//
+// - a number of aspects of the shader and the vertex format
+// are configurable; the library generally takes care of
+// coordinating the vertex format with the mesh for you.
+//
+//
+// FEATURES (SHADER PERSPECTIVE)
+//
+// - vertices aligned on integer lattice, z on multiples of 0.5
+// - per-vertex "lighting" or "ambient occlusion" value (6 bits)
+// - per-vertex texture crossfade (3 bits)
+//
+// - per-face texture #1 id (8-bit index into array texture)
+// - per-face texture #2 id (8-bit index into second array texture)
+// - per-face color (6-bit palette index, 2 bits of per-texture boolean enable)
+// - per-face 5-bit normal for lighting calculations & texture coord computation
+// - per-face 2-bit texture matrix rotation to rotate faces
+//
+// - indexed-by-texture-id scale factor (separate for texture #1 and texture #2)
+// - indexed-by-texture-#2-id blend mode (alpha composite or modulate/multiply);
+// the first is good for decals, the second for detail textures, "light maps",
+// etc; both modes are controlled by texture #2's alpha, scaled by the
+// per-vertex texture crossfade and the per-face color (if enabled on texture #2);
+// modulate/multiply multiplies by an extra factor of 2.0 so that if you
+// make detail maps whose average brightness is 0.5 everything works nicely.
+//
+// - ambient lighting: half-lambert directional plus constant, all scaled by vertex ao
+// - face can be fullbright (emissive), controlled by per-face color
+// - installable lighting, with default single-point-light
+// - installable fog, with default hacked smoothstep
+//
+// Note that all the variations of lighting selection and texture
+// blending are run-time conditions in the shader, so they can be
+// intermixed in a single mesh.
+//
+//
+// INTEGRATION ARC
+//
+// The way to get this library to work from scratch is to do the following:
+//
+// Step 1. define STBVOX_CONFIG_MODE to 0
+//
+// This mode uses only vertex attributes and uniforms, and is easiest
+// to get working. It requires 32 bytes per quad and limits the
+// size of some tables to avoid hitting uniform limits.
+//
+// Step 2. define STBVOX_CONFIG_MODE to 1
+//
+// This requires using a texture buffer to store the quad data,
+// reducing the size to 20 bytes per quad.
+//
+// Step 3: define STBVOX_CONFIG_PREFER_TEXBUFFER
+//
+// This causes some uniforms to be stored as texture buffers
+// instead. This increases the size of some of those tables,
+// and avoids a potential slow path (gathering non-uniform
+// data from uniforms) on some hardware.
+//
+// In the future I hope to add additional modes that have significantly
+// smaller meshes but reduce features, down as small as 6 bytes per quad.
+// See elsewhere in this file for a table of candidate modes. Switching
+// to a mode will require changing some of your mesh creation code, but
+// everything else should be seamless. (And I'd like to change the API
+// so that mesh creation is data-driven the way the uniforms are, and
+// then you wouldn't even have to change anything but the mode number.)
+//
+//
+// IMPROVEMENTS FOR SHIP-WORTHY PROGRAMS USING THIS LIBRARY
+//
+// I currently tolerate a certain level of "bugginess" in this library.
+//
+// I'm referring to things which look a little wrong (as long as they
+// don't cause holes or cracks in the output meshes), or things which
+// do not produce as optimal a mesh as possible. Notable examples:
+//
+// - incorrect lighting on slopes
+// - inefficient meshes for vheight blocks
+//
+// I am willing to do the work to improve these things if someone is
+// going to ship a substantial program that would be improved by them.
+// (It need not be commercial, nor need it be a game.) I just didn't
+// want to do the work up front if it might never be leveraged. So just
+// submit a bug report as usual (github is preferred), but add a note
+// that this is for a thing that is really going to ship. (That means
+// you need to be far enough into the project that it's clear you're
+// committed to it; not during early exploratory development.)
+//
+//
+// VOXEL MESH API
+//
+// Context
+//
+// To understand the API, make sure you first understand the feature set
+// listed above.
+//
+// Because the vertices are compact, they have very limited spatial
+// precision. Thus a single mesh can only contain the data for a limited
+// area. To make very large voxel maps, you'll need to build multiple
+// vertex buffers. (But you want this anyway for frustum culling.)
+//
+// Each generated mesh has three components:
+// - vertex data (vertex buffer)
+// - face data (optional, stored in texture buffer)
+// - mesh transform (uniforms)
+//
+// Once you've generated the mesh with this library, it's up to you
+// to upload it to the GPU, to keep track of the state, and to render
+// it.
+//
+// Concept
+//
+// The basic design is that you pass in one or more 3D arrays; each array
+// is (typically) one-byte-per-voxel and contains information about one
+// or more properties of some particular voxel property.
+//
+// Because there is so much per-vertex and per-face data possible
+// in the output, and each voxel can have 6 faces and 8 vertices, it
+// would require an very large data structure to describe all
+// of the possibilities, and this would cause the mesh-creation
+// process to be slow. Instead, the API provides multiple ways
+// to express each property, some more compact, others less so;
+// each such way has some limitations on what it can express.
+//
+// Note that there are so many paths and combinations, not all of them
+// have been tested. Just report bugs and I'll fix 'em.
+//
+// Details
+//
+// See the API documentation in the header-file section.
+//
+//
+// CONTRIBUTORS
+//
+// Features Porting Bugfixes & Warnings
+// Sean Barrett github:r-leyh Jesus Fernandez
+// Miguel Lechon github:Arbeiterunfallversicherungsgesetz
+// Thomas Frase James Hofmann
+// Stephen Olsen
+//
+// VERSION HISTORY
+//
+// 0.84 (2016-04-02) fix GLSL syntax error on glModelView path
+// 0.83 (2015-09-13) remove non-constant struct initializers to support more compilers
+// 0.82 (2015-08-01) added input.packed_compact to store rot, vheight & texlerp efficiently
+// fix broken tex_overlay2
+// 0.81 (2015-05-28) fix broken STBVOX_CONFIG_OPTIMIZED_VHEIGHT
+// 0.80 (2015-04-11) fix broken STBVOX_CONFIG_ROTATION_IN_LIGHTING refactoring
+// change STBVOX_MAKE_LIGHTING to STBVOX_MAKE_LIGHTING_EXT so
+// that header defs don't need to see config vars
+// add STBVOX_CONFIG_VHEIGHT_IN_LIGHTING and other vheight fixes
+// added documentation for vheight ("weird slopes")
+// 0.79 (2015-04-01) fix the missing types from 0.78; fix string constants being const
+// 0.78 (2015-04-02) bad "#else", compile as C++
+// 0.77 (2015-04-01) documentation tweaks, rename config var to STB_VOXEL_RENDER_STATIC
+// 0.76 (2015-04-01) typos, signed/unsigned shader issue, more documentation
+// 0.75 (2015-04-01) initial release
+//
+//
+// HISTORICAL FOUNDATION
+//
+// stb_voxel_render 20-byte quads 2015/01
+// zmc engine 32-byte quads 2013/12
+// zmc engine 96-byte quads 2011/10
+//
+//
+// LICENSE
+//
+// This software is dual-licensed to the public domain and under the following
+// license: you are granted a perpetual, irrevocable license to copy, modify,
+// publish, and distribute this file as you see fit.
+
+#ifndef INCLUDE_STB_VOXEL_RENDER_H
+#define INCLUDE_STB_VOXEL_RENDER_H
+
+#include <stdlib.h>
+
+typedef struct stbvox_mesh_maker stbvox_mesh_maker;
+typedef struct stbvox_input_description stbvox_input_description;
+
+#ifdef STB_VOXEL_RENDER_STATIC
+#define STBVXDEC static
+#else
+#define STBVXDEC extern
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// CONFIGURATION MACROS
+//
+// #define STBVOX_CONFIG_MODE <integer> // REQUIRED
+// Configures the overall behavior of stb_voxel_render. This
+// can affect the shaders, the uniform info, and other things.
+// (If you need more than one mode in the same app, you can
+// use STB_VOXEL_RENDER_STATIC to create multiple versions
+// in separate files, and then wrap them.)
+//
+// Mode value Meaning
+// 0 Textured blocks, 32-byte quads
+// 1 Textured blocks, 20-byte quads
+// 20 Untextured blocks, 32-byte quads
+// 21 Untextured blocks, 20-byte quads
+//
+//
+// #define STBVOX_CONFIG_PRECISION_Z <integer> // OPTIONAL
+// Defines the number of bits of fractional position for Z.
+// Only 0 or 1 are valid. 1 is the default. If 0, then a
+// single mesh has twice the legal Z range; e.g. in
+// modes 0,1,20,21, Z in the mesh can extend to 511 instead
+// of 255. However, half-height blocks cannot be used.
+//
+// All of the following just #ifdef tested so need no values, and are optional.
+//
+// STBVOX_CONFIG_BLOCKTYPE_SHORT
+// use unsigned 16-bit values for 'blocktype' in the input instead of 8-bit values
+//
+// STBVOX_CONFIG_OPENGL_MODELVIEW
+// use the gl_ModelView matrix rather than the explicit uniform
+//
+// STBVOX_CONFIG_HLSL
+// NOT IMPLEMENTED! Define HLSL shaders instead of GLSL shaders
+//
+// STBVOX_CONFIG_PREFER_TEXBUFFER
+// Stores many of the uniform arrays in texture buffers intead,
+// so they can be larger and may be more efficient on some hardware.
+//
+// STBVOX_CONFIG_LIGHTING_SIMPLE
+// Creates a simple lighting engine with a single point light source
+// in addition to the default half-lambert ambient light.
+//
+// STBVOX_CONFIG_LIGHTING
+// Declares a lighting function hook; you must append a lighting function
+// to the shader before compiling it:
+// vec3 compute_lighting(vec3 pos, vec3 norm, vec3 albedo, vec3 ambient);
+// 'ambient' is the half-lambert ambient light with vertex ambient-occlusion applied
+//
+// STBVOX_CONFIG_FOG_SMOOTHSTEP
+// Defines a simple unrealistic fog system designed to maximize
+// unobscured view distance while not looking too weird when things
+// emerge from the fog. Configured using an extra array element
+// in the STBVOX_UNIFORM_ambient uniform.
+//
+// STBVOX_CONFIG_FOG
+// Defines a fog function hook; you must append a fog function to
+// the shader before compiling it:
+// vec3 compute_fog(vec3 color, vec3 relative_pos, float fragment_alpha);
+// "color" is the incoming pre-fogged color, fragment_alpha is the alpha value,
+// and relative_pos is the vector from the point to the camera in worldspace
+//
+// STBVOX_CONFIG_DISABLE_TEX2
+// This disables all processing of texture 2 in the shader in case
+// you don't use it. Eventually this will be replaced with a mode
+// that omits the unused data entirely.
+//
+// STBVOX_CONFIG_TEX1_EDGE_CLAMP
+// STBVOX_CONFIG_TEX2_EDGE_CLAMP
+// If you want to edge clamp the textures, instead of letting them wrap,
+// set this flag. By default stb_voxel_render relies on texture wrapping
+// to simplify texture coordinate generation. This flag forces it to do
+// it correctly, although there can still be minor artifacts.
+//
+// STBVOX_CONFIG_ROTATION_IN_LIGHTING
+// Changes the meaning of the 'lighting' mesher input variable to also
+// store the rotation; see later discussion.
+//
+// STBVOX_CONFIG_VHEIGHT_IN_LIGHTING
+// Changes the meaning of the 'lighting' mesher input variable to also
+// store the vheight; see later discussion. Cannot use both this and
+// the previous variable.
+//
+// STBVOX_CONFIG_PREMULTIPLIED_ALPHA
+// Adjusts the shader calculations on the assumption that tex1.rgba,
+// tex2.rgba, and color.rgba all use premultiplied values, and that
+// the output of the fragment shader should be premultiplied.
+//
+// STBVOX_CONFIG_UNPREMULTIPLY
+// Only meaningful if STBVOX_CONFIG_PREMULTIPLIED_ALPHA is defined.
+// Changes the behavior described above so that the inputs are
+// still premultiplied alpha, but the output of the fragment
+// shader is not premultiplied alpha. This is needed when allowing
+// non-unit alpha values but not doing alpha-blending (for example
+// when alpha testing).
+//
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// MESHING
+//
+// A mesh represents a (typically) small chunk of a larger world.
+// Meshes encode coordinates using small integers, so those
+// coordinates must be relative to some base location.
+// All of the coordinates in the functions below use
+// these relative coordinates unless explicitly stated
+// otherwise.
+//
+// Input to the meshing step is documented further down
+
+STBVXDEC void stbvox_init_mesh_maker(stbvox_mesh_maker *mm);
+// Call this function to initialize a mesh-maker context structure
+// used to build meshes. You should have one context per thread
+// that's building meshes.
+
+STBVXDEC void stbvox_set_buffer(stbvox_mesh_maker *mm, int mesh, int slot, void *buffer, size_t len);
+// Call this to set the buffer into which stbvox will write the mesh
+// it creates. It can build more than one mesh in parallel (distinguished
+// by the 'mesh' parameter), and each mesh can be made up of more than
+// one buffer (distinguished by the 'slot' parameter).
+//
+// Multiple meshes are under your control; use the 'selector' input
+// variable to choose which mesh each voxel's vertices are written to.
+// For example, you can use this to generate separate meshes for opaque
+// and transparent data.
+//
+// You can query the number of slots by calling stbvox_get_buffer_count
+// described below. The meaning of the buffer for each slot depends
+// on STBVOX_CONFIG_MODE.
+//
+// In mode 0 & mode 20, there is only one slot. The mesh data for that
+// slot is two interleaved vertex attributes: attr_vertex, a single
+// 32-bit uint, and attr_face, a single 32-bit uint.
+//
+// In mode 1 & mode 21, there are two slots. The first buffer should
+// be four times as large as the second buffer. The first buffer
+// contains a single vertex attribute: 'attr_vertex', a single 32-bit uint.
+// The second buffer contains texture buffer data (an array of 32-bit uints)
+// that will be accessed through the sampler identified by STBVOX_UNIFORM_face_data.
+
+STBVXDEC int stbvox_get_buffer_count(stbvox_mesh_maker *mm);
+// Returns the number of buffers needed per mesh as described above.
+
+STBVXDEC int stbvox_get_buffer_size_per_quad(stbvox_mesh_maker *mm, int slot);
+// Returns how much of a given buffer will get used per quad. This
+// allows you to choose correct relative sizes for each buffer, although
+// the values are fixed based on the configuration you've selected at
+// compile time, and the details are described in stbvox_set_buffer.
+
+STBVXDEC void stbvox_set_default_mesh(stbvox_mesh_maker *mm, int mesh);
+// Selects which mesh the mesher will output to (see previous function)
+// if the input doesn't specify a per-voxel selector. (I doubt this is
+// useful, but it's here just in case.)
+
+STBVXDEC stbvox_input_description *stbvox_get_input_description(stbvox_mesh_maker *mm);
+// This function call returns a pointer to the stbvox_input_description part
+// of stbvox_mesh_maker (which you should otherwise treat as opaque). You
+// zero this structure, then fill out the relevant pointers to the data
+// describing your voxel object/world.
+//
+// See further documentation at the description of stbvox_input_description below.
+
+STBVXDEC void stbvox_set_input_stride(stbvox_mesh_maker *mm, int x_stride_in_elements, int y_stride_in_elements);
+// This sets the stride between successive elements of the 3D arrays
+// in the stbvox_input_description. Z values are always stored consecutively.
+// (The preferred coordinate system for stbvox is X right, Y forwards, Z up.)
+
+STBVXDEC void stbvox_set_input_range(stbvox_mesh_maker *mm, int x0, int y0, int z0, int x1, int y1, int z1);
+// This sets the range of values in the 3D array for the voxels that
+// the mesh generator will convert. The lower values are inclusive,
+// the higher values are exclusive, so (0,0,0) to (16,16,16) generates
+// mesh data associated with voxels up to (15,15,15) but no higher.
+//
+// The mesh generate generates faces at the boundary between open space
+// and solid space but associates them with the solid space, so if (15,0,0)
+// is open and (16,0,0) is solid, then the mesh will contain the boundary
+// between them if x0 <= 16 and x1 > 16.
+//
+// Note that the mesh generator will access array elements 1 beyond the
+// limits set in these parameters. For example, if you set the limits
+// to be (0,0,0) and (16,16,16), then the generator will access all of
+// the voxels between (-1,-1,-1) and (16,16,16), including (16,16,16).
+// You may have to do pointer arithmetic to make it work.
+//
+// For example, caveview processes mesh chunks that are 32x32x16, but it
+// does this using input buffers that are 34x34x18.
+//
+// The lower limits are x0 >= 0, y0 >= 0, and z0 >= 0.
+//
+// The upper limits are mode dependent, but all the current methods are
+// limited to x1 < 127, y1 < 127, z1 < 255. Note that these are not
+// powers of two; if you want to use power-of-two chunks (to make
+// it efficient to decide which chunk a coordinate falls in), you're
+// limited to at most x1=64, y1=64, z1=128. For classic Minecraft-style
+// worlds with limited vertical extent, I recommend using a single
+// chunk for the entire height, which limits the height to 255 blocks
+// (one less than Minecraft), and only chunk the map in X & Y.
+
+STBVXDEC int stbvox_make_mesh(stbvox_mesh_maker *mm);
+// Call this function to create mesh data for the currently configured
+// set of input data. This appends to the currently configured mesh output
+// buffer. Returns 1 on success. If there is not enough room in the buffer,
+// it outputs as much as it can, and returns 0; you need to switch output
+// buffers (either by calling stbvox_set_buffer to set new buffers, or
+// by copying the data out and calling stbvox_reset_buffers), and then
+// call this function again without changing any of the input parameters.
+//
+// Note that this function appends; you can call it multiple times to
+// build a single mesh. For example, caveview uses chunks that are
+// 32x32x255, but builds the mesh for it by processing 32x32x16 at atime
+// (this is faster as it is reuses the same 34x34x18 input buffers rather
+// than needing 34x34x257 input buffers).
+
+// Once you're done creating a mesh into a given buffer,
+// consider the following functions:
+
+STBVXDEC int stbvox_get_quad_count(stbvox_mesh_maker *mm, int mesh);
+// Returns the number of quads in the mesh currently generated by mm.
+// This is the sum of all consecutive stbvox_make_mesh runs appending
+// to the same buffer. 'mesh' distinguishes between the multiple user
+// meshes available via 'selector' or stbvox_set_default_mesh.
+//
+// Typically you use this function when you're done building the mesh
+// and want to record how to draw it.
+//
+// Note that there are no index buffers; the data stored in the buffers
+// should be drawn as quads (e.g. with GL_QUAD); if your API does not
+// support quads, you can create a single index buffer large enough to
+// draw your largest vertex buffer, and reuse it for every rendering.
+// (Note that if you use 32-bit indices, you'll use 24 bytes of bandwidth
+// per quad, more than the 20 bytes for the vertex/face mesh data.)
+
+STBVXDEC void stbvox_set_mesh_coordinates(stbvox_mesh_maker *mm, int x, int y, int z);
+// Sets the global coordinates for this chunk, such that (0,0,0) relative
+// coordinates will be at (x,y,z) in global coordinates.
+
+STBVXDEC void stbvox_get_bounds(stbvox_mesh_maker *mm, float bounds[2][3]);
+// Returns the bounds for the mesh in global coordinates. Use this
+// for e.g. frustum culling the mesh. @BUG: this just uses the
+// values from stbvox_set_input_range(), so if you build by
+// appending multiple values, this will be wrong, and you need to
+// set stbvox_set_input_range() to the full size. Someday this
+// will switch to tracking the actual bounds of the *mesh*, though.
+
+STBVXDEC void stbvox_get_transform(stbvox_mesh_maker *mm, float transform[3][3]);
+// Returns the 'transform' data for the shader uniforms. It is your
+// job to set this to the shader before drawing the mesh. It is the
+// only uniform that needs to change per-mesh. Note that it is not
+// a 3x3 matrix, but rather a scale to decode fixed point numbers as
+// floats, a translate from relative to global space, and a special
+// translation for texture coordinate generation that avoids
+// floating-point precision issues. @TODO: currently we add the
+// global translation to the vertex, than multiply by modelview,
+// but this means if camera location and vertex are far from the
+// origin, we lose precision. Need to make a special modelview with
+// the translation (or some of it) factored out to avoid this.
+
+STBVXDEC void stbvox_reset_buffers(stbvox_mesh_maker *mm);
+// Call this function if you're done with the current output buffer
+// but want to reuse it (e.g. you're done appending with
+// stbvox_make_mesh and you've copied the data out to your graphics API
+// so can reuse the buffer).
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// RENDERING
+//
+
+STBVXDEC char *stbvox_get_vertex_shader(void);
+// Returns the (currently GLSL-only) vertex shader.
+
+STBVXDEC char *stbvox_get_fragment_shader(void);
+// Returns the (currently GLSL-only) fragment shader.
+// You can override the lighting and fogging calculations
+// by appending data to the end of these; see the #define
+// documentation for more information.
+
+STBVXDEC char *stbvox_get_fragment_shader_alpha_only(void);
+// Returns a slightly cheaper fragment shader that computes
+// alpha but not color. This is useful for e.g. a depth-only
+// pass when using alpha test.
+
+typedef struct stbvox_uniform_info stbvox_uniform_info;
+
+STBVXDEC int stbvox_get_uniform_info(stbvox_uniform_info *info, int uniform);
+// Gets the information about a uniform necessary for you to
+// set up each uniform with a minimal amount of explicit code.
+// See the sample code after the structure definition for stbvox_uniform_info,
+// further down in this header section.
+//
+// "uniform" is from the list immediately following. For many
+// of these, default values are provided which you can set.
+// Most values are shared for most draw calls; e.g. for stateful
+// APIs you can set most of the state only once. Only
+// STBVOX_UNIFORM_transform needs to change per draw call.
+//
+// STBVOX_UNIFORM_texscale
+// 64- or 128-long vec4 array. (128 only if STBVOX_CONFIG_PREFER_TEXBUFFER)
+// x: scale factor to apply to texture #1. must be a power of two. 1.0 means 'face-sized'
+// y: scale factor to apply to texture #2. must be a power of two. 1.0 means 'face-sized'
+// z: blend mode indexed by texture #2. 0.0 is alpha compositing; 1.0 is multiplication.
+// w: unused currently. @TODO use to support texture animation?
+//
+// Texscale is indexed by the bottom 6 or 7 bits of the texture id; thus for
+// example the texture at index 0 in the array and the texture in index 128 of
+// the array must be scaled the same. This means that if you only have 64 or 128
+// unique textures, they all get distinct values anyway; otherwise you have
+// to group them in pairs or sets of four.
+//
+// STBVOX_UNIFORM_ambient
+// 4-long vec4 array:
+// ambient[0].xyz - negative of direction of a directional light for half-lambert
+// ambient[1].rgb - color of light scaled by NdotL (can be negative)
+// ambient[2].rgb - constant light added to above calculation;
+// effectively light ranges from ambient[2]-ambient[1] to ambient[2]+ambient[1]
+// ambient[3].rgb - fog color for STBVOX_CONFIG_FOG_SMOOTHSTEP
+// ambient[3].a - reciprocal of squared distance of farthest fog point (viewing distance)
+
+
+ // +----- has a default value
+ // | +-- you should always use the default value
+enum // V V
+{ // ------------------------------------------------
+ STBVOX_UNIFORM_face_data, // n the sampler with the face texture buffer
+ STBVOX_UNIFORM_transform, // n the transform data from stbvox_get_transform
+ STBVOX_UNIFORM_tex_array, // n an array of two texture samplers containing the two texture arrays
+ STBVOX_UNIFORM_texscale, // Y a table of texture properties, see above
+ STBVOX_UNIFORM_color_table, // Y 64 vec4 RGBA values; a default palette is provided; if A > 1.0, fullbright
+ STBVOX_UNIFORM_normals, // Y Y table of normals, internal-only
+ STBVOX_UNIFORM_texgen, // Y Y table of texgen vectors, internal-only
+ STBVOX_UNIFORM_ambient, // n lighting & fog info, see above
+ STBVOX_UNIFORM_camera_pos, // Y camera position in global voxel space (for lighting & fog)
+
+ STBVOX_UNIFORM_count,
+};
+
+enum
+{
+ STBVOX_UNIFORM_TYPE_none,
+ STBVOX_UNIFORM_TYPE_sampler,
+ STBVOX_UNIFORM_TYPE_vec2,
+ STBVOX_UNIFORM_TYPE_vec3,
+ STBVOX_UNIFORM_TYPE_vec4,
+};
+
+struct stbvox_uniform_info
+{
+ int type; // which type of uniform
+ int bytes_per_element; // the size of each uniform array element (e.g. vec3 = 12 bytes)
+ int array_length; // length of the uniform array
+ char *name; // name in the shader @TODO use numeric binding
+ float *default_value; // if not NULL, you can use this as the uniform pointer
+ int use_tex_buffer; // if true, then the uniform is a sampler but the data can come from default_value
+};
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Uniform sample code
+//
+
+#if 0
+// Run this once per frame before drawing all the meshes.
+// You still need to separately set the 'transform' uniform for every mesh.
+void setup_uniforms(GLuint shader, float camera_pos[4], GLuint tex1, GLuint tex2)
+{
+ int i;
+ glUseProgram(shader); // so uniform binding works
+ for (i=0; i < STBVOX_UNIFORM_count; ++i) {
+ stbvox_uniform_info sui;
+ if (stbvox_get_uniform_info(&sui, i)) {
+ GLint loc = glGetUniformLocation(shader, sui.name);
+ if (loc != 0) {
+ switch (i) {
+ case STBVOX_UNIFORM_camera_pos: // only needed for fog
+ glUniform4fv(loc, sui.array_length, camera_pos);
+ break;
+
+ case STBVOX_UNIFORM_tex_array: {
+ GLuint tex_unit[2] = { 0, 1 }; // your choice of samplers
+ glUniform1iv(loc, 2, tex_unit);
+
+ glActiveTexture(GL_TEXTURE0 + tex_unit[0]); glBindTexture(GL_TEXTURE_2D_ARRAY, tex1);
+ glActiveTexture(GL_TEXTURE0 + tex_unit[1]); glBindTexture(GL_TEXTURE_2D_ARRAY, tex2);
+ glActiveTexture(GL_TEXTURE0); // reset to default
+ break;
+ }
+
+ case STBVOX_UNIFORM_face_data:
+ glUniform1i(loc, SAMPLER_YOU_WILL_BIND_PER_MESH_FACE_DATA_TO);
+ break;
+
+ case STBVOX_UNIFORM_ambient: // you definitely want to override this
+ case STBVOX_UNIFORM_color_table: // you might want to override this
+ case STBVOX_UNIFORM_texscale: // you may want to override this
+ glUniform4fv(loc, sui.array_length, sui.default_value);
+ break;
+
+ case STBVOX_UNIFORM_normals: // you never want to override this
+ case STBVOX_UNIFORM_texgen: // you never want to override this
+ glUniform3fv(loc, sui.array_length, sui.default_value);
+ break;
+ }
+ }
+ }
+ }
+}
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// INPUT TO MESHING
+//
+
+// Shapes of blocks that aren't always cubes
+enum
+{
+ STBVOX_GEOM_empty,
+ STBVOX_GEOM_knockout, // creates a hole in the mesh
+ STBVOX_GEOM_solid,
+ STBVOX_GEOM_transp, // solid geometry, but transparent contents so neighbors generate normally, unless same blocktype
+
+ // following 4 can be represented by vheight as well
+ STBVOX_GEOM_slab_upper,
+ STBVOX_GEOM_slab_lower,
+ STBVOX_GEOM_floor_slope_north_is_top,
+ STBVOX_GEOM_ceil_slope_north_is_bottom,
+
+ STBVOX_GEOM_floor_slope_north_is_top_as_wall_UNIMPLEMENTED, // same as floor_slope above, but uses wall's texture & texture projection
+ STBVOX_GEOM_ceil_slope_north_is_bottom_as_wall_UNIMPLEMENTED,
+ STBVOX_GEOM_crossed_pair, // corner-to-corner pairs, with normal vector bumped upwards
+ STBVOX_GEOM_force, // like GEOM_transp, but faces visible even if neighbor is same type, e.g. minecraft fancy leaves
+
+ // these access vheight input
+ STBVOX_GEOM_floor_vheight_03 = 12, // diagonal is SW-NE
+ STBVOX_GEOM_floor_vheight_12, // diagonal is SE-NW
+ STBVOX_GEOM_ceil_vheight_03,
+ STBVOX_GEOM_ceil_vheight_12,
+
+ STBVOX_GEOM_count, // number of geom cases
+};
+
+enum
+{
+ STBVOX_FACE_east,
+ STBVOX_FACE_north,
+ STBVOX_FACE_west,
+ STBVOX_FACE_south,
+ STBVOX_FACE_up,
+ STBVOX_FACE_down,
+
+ STBVOX_FACE_count,
+};
+
+#ifdef STBVOX_CONFIG_BLOCKTYPE_SHORT
+typedef unsigned short stbvox_block_type;
+#else
+typedef unsigned char stbvox_block_type;
+#endif
+
+// 24-bit color
+typedef struct
+{
+ unsigned char r,g,b;
+} stbvox_rgb;
+
+#define STBVOX_COLOR_TEX1_ENABLE 64
+#define STBVOX_COLOR_TEX2_ENABLE 128
+
+// This is the data structure you fill out. Most of the arrays can be
+// NULL, except when one is required to get the value to index another.
+//
+// The compass system used in the following descriptions is:
+// east means increasing x
+// north means increasing y
+// up means increasing z
+struct stbvox_input_description
+{
+ unsigned char lighting_at_vertices;
+ // The default is lighting values (i.e. ambient occlusion) are at block
+ // center, and the vertex light is gathered from those adjacent block
+ // centers that the vertex is facing. This makes smooth lighting
+ // consistent across adjacent faces with the same orientation.
+ //
+ // Setting this flag to non-zero gives you explicit control
+ // of light at each vertex, but now the lighting/ao will be
+ // shared by all vertices at the same point, even if they
+ // have different normals.
+
+ // these are mostly 3D maps you use to define your voxel world, using x_stride and y_stride
+ // note that for cache efficiency, you want to use the block_foo palettes as much as possible instead
+
+ stbvox_rgb *rgb;
+ // Indexed by 3D coordinate.
+ // 24-bit voxel color for STBVOX_CONFIG_MODE = 20 or 21 only
+
+ unsigned char *lighting;
+ // Indexed by 3D coordinate. The lighting value / ambient occlusion
+ // value that is used to define the vertex lighting values.
+ // The raw lighting values are defined at the center of blocks
+ // (or at vertex if 'lighting_at_vertices' is true).
+ //
+ // If the macro STBVOX_CONFIG_ROTATION_IN_LIGHTING is defined,
+ // then an additional 2-bit block rotation value is stored
+ // in this field as well.
+ //
+ // Encode with STBVOX_MAKE_LIGHTING_EXT(lighting,rot)--here
+ // 'lighting' should still be 8 bits, as the macro will
+ // discard the bottom bits automatically. Similarly, if
+ // using STBVOX_CONFIG_VHEIGHT_IN_LIGHTING, encode with
+ // STBVOX_MAKE_LIGHTING_EXT(lighting,vheight).
+ //
+ // (Rationale: rotation needs to be independent of blocktype,
+ // but is only 2 bits so doesn't want to be its own array.
+ // Lighting is the one thing that was likely to already be
+ // in use and that I could easily steal 2 bits from.)
+
+ stbvox_block_type *blocktype;
+ // Indexed by 3D coordinate. This is a core "block type" value, which is used
+ // to index into other arrays; essentially a "palette". This is much more
+ // memory-efficient and performance-friendly than storing the values explicitly,
+ // but only makes sense if the values are always synchronized.
+ //
+ // If a voxel's blocktype is 0, it is assumed to be empty (STBVOX_GEOM_empty),
+ // and no other blocktypes should be STBVOX_GEOM_empty. (Only if you do not
+ // have blocktypes should STBVOX_GEOM_empty ever used.)
+ //
+ // Normally it is an unsigned byte, but you can override it to be
+ // a short if you have too many blocktypes.
+
+ unsigned char *geometry;
+ // Indexed by 3D coordinate. Contains the geometry type for the block.
+ // Also contains a 2-bit rotation for how the whole block is rotated.
+ // Also includes a 2-bit vheight value when using shared vheight values.
+ // See the separate vheight documentation.
+ // Encode with STBVOX_MAKE_GEOMETRY(geom, rot, vheight)
+
+ unsigned char *block_geometry;
+ // Array indexed by blocktype containing the geometry for this block, plus
+ // a 2-bit "simple rotation". Note rotation has limited use since it's not
+ // independent of blocktype.
+ //
+ // Encode with STBVOX_MAKE_GEOMETRY(geom,simple_rot,0)
+
+ unsigned char *block_tex1;
+ // Array indexed by blocktype containing the texture id for texture #1.
+
+ unsigned char (*block_tex1_face)[6];
+ // Array indexed by blocktype and face containing the texture id for texture #1.
+ // The N/E/S/W face choices can be rotated by one of the rotation selectors;
+ // The top & bottom face textures will rotate to match.
+ // Note that it only makes sense to use one of block_tex1 or block_tex1_face;
+ // this pattern repeats throughout and this notice is not repeated.
+
+ unsigned char *tex2;
+ // Indexed by 3D coordinate. Contains the texture id for texture #2
+ // to use on all faces of the block.
+
+ unsigned char *block_tex2;
+ // Array indexed by blocktype containing the texture id for texture #2.
+
+ unsigned char (*block_tex2_face)[6];
+ // Array indexed by blocktype and face containing the texture id for texture #2.
+ // The N/E/S/W face choices can be rotated by one of the rotation selectors;
+ // The top & bottom face textures will rotate to match.
+
+ unsigned char *color;
+ // Indexed by 3D coordinate. Contains the color for all faces of the block.
+ // The core color value is 0..63.
+ // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable)
+
+ unsigned char *block_color;
+ // Array indexed by blocktype containing the color value to apply to the faces.
+ // The core color value is 0..63.
+ // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable)
+
+ unsigned char (*block_color_face)[6];
+ // Array indexed by blocktype and face containing the color value to apply to that face.
+ // The core color value is 0..63.
+ // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable)
+
+ unsigned char *block_texlerp;
+ // Array indexed by blocktype containing 3-bit scalar for texture #2 alpha
+ // (known throughout as 'texlerp'). This is constant over every face even
+ // though the property is potentially per-vertex.
+
+ unsigned char (*block_texlerp_face)[6];
+ // Array indexed by blocktype and face containing 3-bit scalar for texture #2 alpha.
+ // This is constant over the face even though the property is potentially per-vertex.
+
+ unsigned char *block_vheight;
+ // Array indexed by blocktype containing the vheight values for the
+ // top or bottom face of this block. These will rotate properly if the
+ // block is rotated. See discussion of vheight.
+ // Encode with STBVOX_MAKE_VHEIGHT(sw_height, se_height, nw_height, ne_height)
+
+ unsigned char *selector;
+ // Array indexed by 3D coordinates indicating which output mesh to select.
+
+ unsigned char *block_selector;
+ // Array indexed by blocktype indicating which output mesh to select.
+
+ unsigned char *side_texrot;
+ // Array indexed by 3D coordinates encoding 2-bit texture rotations for the
+ // faces on the E/N/W/S sides of the block.
+ // Encode with STBVOX_MAKE_SIDE_TEXROT(rot_e, rot_n, rot_w, rot_s)
+
+ unsigned char *block_side_texrot;
+ // Array indexed by blocktype encoding 2-bit texture rotations for the faces
+ // on the E/N/W/S sides of the block.
+ // Encode with STBVOX_MAKE_SIDE_TEXROT(rot_e, rot_n, rot_w, rot_s)
+
+ unsigned char *overlay; // index into palettes listed below
+ // Indexed by 3D coordinate. If 0, there is no overlay. If non-zero,
+ // it indexes into to the below arrays and overrides the values
+ // defined by the blocktype.
+
+ unsigned char (*overlay_tex1)[6];
+ // Array indexed by overlay value and face, containing an override value
+ // for the texture id for texture #1. If 0, the value defined by blocktype
+ // is used.
+
+ unsigned char (*overlay_tex2)[6];
+ // Array indexed by overlay value and face, containing an override value
+ // for the texture id for texture #2. If 0, the value defined by blocktype
+ // is used.
+
+ unsigned char (*overlay_color)[6];
+ // Array indexed by overlay value and face, containing an override value
+ // for the face color. If 0, the value defined by blocktype is used.
+
+ unsigned char *overlay_side_texrot;
+ // Array indexed by overlay value, encoding 2-bit texture rotations for the faces
+ // on the E/N/W/S sides of the block.
+ // Encode with STBVOX_MAKE_SIDE_TEXROT(rot_e, rot_n, rot_w, rot_s)
+
+ unsigned char *rotate;
+ // Indexed by 3D coordinate. Allows independent rotation of several
+ // parts of the voxel, where by rotation I mean swapping textures
+ // and colors between E/N/S/W faces.
+ // Block: rotates anything indexed by blocktype
+ // Overlay: rotates anything indexed by overlay
+ // EColor: rotates faces defined in ecolor_facemask
+ // Encode with STBVOX_MAKE_MATROT(block,overlay,ecolor)
+
+ unsigned char *tex2_for_tex1;
+ // Array indexed by tex1 containing the texture id for texture #2.
+ // You can use this if the two are always/almost-always strictly
+ // correlated (e.g. if tex2 is a detail texture for tex1), as it
+ // will be more efficient (touching fewer cache lines) than using
+ // e.g. block_tex2_face.
+
+ unsigned char *tex2_replace;
+ // Indexed by 3D coordinate. Specifies the texture id for texture #2
+ // to use on a single face of the voxel, which must be E/N/W/S (not U/D).
+ // The texture id is limited to 6 bits unless tex2_facemask is also
+ // defined (see below).
+ // Encode with STBVOX_MAKE_TEX2_REPLACE(tex2, face)
+
+ unsigned char *tex2_facemask;
+ // Indexed by 3D coordinate. Specifies which of the six faces should
+ // have their tex2 replaced by the value of tex2_replace. In this
+ // case, all 8 bits of tex2_replace are used as the texture id.
+ // Encode with STBVOX_MAKE_FACE_MASK(east,north,west,south,up,down)
+
+ unsigned char *extended_color;
+ // Indexed by 3D coordinate. Specifies a value that indexes into
+ // the ecolor arrays below (both of which must be defined).
+
+ unsigned char *ecolor_color;
+ // Indexed by extended_color value, specifies an optional override
+ // for the color value on some faces.
+ // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable)
+
+ unsigned char *ecolor_facemask;
+ // Indexed by extended_color value, this specifies which faces the
+ // color in ecolor_color should be applied to. The faces can be
+ // independently rotated by the ecolor value of 'rotate', if it exists.
+ // Encode with STBVOX_MAKE_FACE_MASK(e,n,w,s,u,d)
+
+ unsigned char *color2;
+ // Indexed by 3D coordinates, specifies an alternative color to apply
+ // to some of the faces of the block.
+ // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable)
+
+ unsigned char *color2_facemask;
+ // Indexed by 3D coordinates, specifies which faces should use the
+ // color defined in color2. No rotation value is applied.
+ // Encode with STBVOX_MAKE_FACE_MASK(e,n,w,s,u,d)
+
+ unsigned char *color3;
+ // Indexed by 3D coordinates, specifies an alternative color to apply
+ // to some of the faces of the block.
+ // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable)
+
+ unsigned char *color3_facemask;
+ // Indexed by 3D coordinates, specifies which faces should use the
+ // color defined in color3. No rotation value is applied.
+ // Encode with STBVOX_MAKE_FACE_MASK(e,n,w,s,u,d)
+
+ unsigned char *texlerp_simple;
+ // Indexed by 3D coordinates, this is the smallest texlerp encoding
+ // that can do useful work. It consits of three values: baselerp,
+ // vertlerp, and face_vertlerp. Baselerp defines the value
+ // to use on all of the faces but one, from the STBVOX_TEXLERP_BASE
+ // values. face_vertlerp is one of the 6 face values (or STBVOX_FACE_NONE)
+ // which specifies the face should use the vertlerp values.
+ // Vertlerp defines a lerp value at every vertex of the mesh.
+ // Thus, one face can have per-vertex texlerp values, and those
+ // values are encoded in the space so that they will be shared
+ // by adjacent faces that also use vertlerp, allowing continuity
+ // (this is used for the "texture crossfade" bit of the release video).
+ // Encode with STBVOX_MAKE_TEXLERP_SIMPLE(baselerp, vertlerp, face_vertlerp)
+
+ // The following texlerp encodings are experimental and maybe not
+ // that useful.
+
+ unsigned char *texlerp;
+ // Indexed by 3D coordinates, this defines four values:
+ // vertlerp is a lerp value at every vertex of the mesh (using STBVOX_TEXLERP_BASE values).
+ // ud is the value to use on up and down faces, from STBVOX_TEXLERP_FACE values
+ // ew is the value to use on east and west faces, from STBVOX_TEXLERP_FACE values
+ // ns is the value to use on north and south faces, from STBVOX_TEXLERP_FACE values
+ // If any of ud, ew, or ns is STBVOX_TEXLERP_FACE_use_vert, then the
+ // vertlerp values for the vertices are gathered and used for those faces.
+ // Encode with STBVOX_MAKE_TEXLERP(vertlerp,ud,ew,sw)
+
+ unsigned short *texlerp_vert3;
+ // Indexed by 3D coordinates, this works with texlerp and
+ // provides a unique texlerp value for every direction at
+ // every vertex. The same rules of whether faces share values
+ // applies. The STBVOX_TEXLERP_FACE vertlerp value defined in
+ // texlerp is only used for the down direction. The values at
+ // each vertex in other directions are defined in this array,
+ // and each uses the STBVOX_TEXLERP3 values (i.e. full precision
+ // 3-bit texlerp values).
+ // Encode with STBVOX_MAKE_VERT3(vertlerp_e,vertlerp_n,vertlerp_w,vertlerp_s,vertlerp_u)
+
+ unsigned short *texlerp_face3; // e:3,n:3,w:3,s:3,u:2,d:2
+ // Indexed by 3D coordinates, this provides a compact way to
+ // fully specify the texlerp value indepenendly for every face,
+ // but doesn't allow per-vertex variation. E/N/W/S values are
+ // encoded using STBVOX_TEXLERP3 values, whereas up and down
+ // use STBVOX_TEXLERP_SIMPLE values.
+ // Encode with STBVOX_MAKE_FACE3(face_e,face_n,face_w,face_s,face_u,face_d)
+
+ unsigned char *vheight; // STBVOX_MAKE_VHEIGHT -- sw:2, se:2, nw:2, ne:2, doesn't rotate
+ // Indexed by 3D coordinates, this defines the four
+ // vheight values to use if the geometry is STBVOX_GEOM_vheight*.
+ // See the vheight discussion.
+
+ unsigned char *packed_compact;
+ // Stores block rotation, vheight, and texlerp values:
+ // block rotation: 2 bits
+ // vertex vheight: 2 bits
+ // use_texlerp : 1 bit
+ // vertex texlerp: 3 bits
+ // If STBVOX_CONFIG_UP_TEXLERP_PACKED is defined, then 'vertex texlerp' is
+ // used for up faces if use_texlerp is 1. If STBVOX_CONFIG_DOWN_TEXLERP_PACKED
+ // is defined, then 'vertex texlerp' is used for down faces if use_texlerp is 1.
+ // Note if those symbols are defined but packed_compact is NULL, the normal
+ // texlerp default will be used.
+ // Encode with STBVOX_MAKE_PACKED_COMPACT(rot, vheight, texlerp, use_texlerp)
+};
+// @OPTIMIZE allow specializing; build a single struct with all of the
+// 3D-indexed arrays combined so it's AoS instead of SoA for better
+// cache efficiency
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// VHEIGHT DOCUMENTATION
+//
+// "vheight" is the internal name for the special block types
+// with sloped tops or bottoms. "vheight" stands for "vertex height".
+//
+// Note that these blocks are very flexible (there are 256 of them,
+// although at least 17 of them should never be used), but they
+// also have a disadvantage that they generate extra invisible
+// faces; the generator does not currently detect whether adjacent
+// vheight blocks hide each others sides, so those side faces are
+// always generated. For a continuous ground terrain, this means
+// that you may generate 5x as many quads as needed. See notes
+// on "improvements for shipping products" in the introduction.
+
+enum
+{
+ STBVOX_VERTEX_HEIGHT_0,
+ STBVOX_VERTEX_HEIGHT_half,
+ STBVOX_VERTEX_HEIGHT_1,
+ STBVOX_VERTEX_HEIGHT_one_and_a_half,
+};
+// These are the "vheight" values. Vheight stands for "vertex height".
+// The idea is that for a "floor vheight" block, you take a cube and
+// reposition the top-most vertices at various heights as specified by
+// the vheight values. Similarly, a "ceiling vheight" block takes a
+// cube and repositions the bottom-most vertices.
+//
+// A floor block only adjusts the top four vertices; the bottom four vertices
+// remain at the bottom of the block. The height values are 2 bits,
+// measured in halves of a block; so you can specify heights of 0/2,
+// 1/2, 2/2, or 3/2. 0 is the bottom of the block, 1 is halfway
+// up the block, 2 is the top of the block, and 3 is halfway up the
+// next block (and actually outside of the block). The value 3 is
+// actually legal for floor vheight (but not ceiling), and allows you to:
+//
+// (A) have smoother terrain by having slopes that cross blocks,
+// e.g. (1,1,3,3) is a regular-seeming slope halfway between blocks
+// (B) make slopes steeper than 45-degrees, e.g. (0,0,3,3)
+//
+// (Because only z coordinates have half-block precision, and x&y are
+// limited to block corner precision, it's not possible to make these
+// things "properly" out of blocks, e.g. a half-slope block on its side
+// or a sloped block halfway between blocks that's made out of two blocks.)
+//
+// If you define STBVOX_CONFIG_OPTIMIZED_VHEIGHT, then the top face
+// (or bottom face for a ceiling vheight block) will be drawn as a
+// single quad even if the four vertex heights aren't planar, and a
+// single normal will be used over the entire quad. If you
+// don't define it, then if the top face is non-planar, it will be
+// split into two triangles, each with their own normal/lighting.
+// (Note that since all output from stb_voxel_render is quad meshes,
+// triangles are actually rendered as degenerate quads.) In this case,
+// the distinction betwen STBVOX_GEOM_floor_vheight_03 and
+// STBVOX_GEOM_floor_vheight_12 comes into play; the former introduces
+// an edge from the SW to NE corner (i.e. from <0,0,?> to <1,1,?>),
+// while the latter introduces an edge from the NW to SE corner
+// (i.e. from <0,1,?> to <1,0,?>.) For a "lazy mesh" look, use
+// exclusively _03 or _12. For a "classic mesh" look, alternate
+// _03 and _12 in a checkerboard pattern. For a "smoothest surface"
+// look, choose the edge based on actual vertex heights.
+//
+// The four vertex heights can come from several places. The simplest
+// encoding is to just use the 'vheight' parameter which stores four
+// explicit vertex heights for every block. This allows total independence,
+// but at the cost of the largest memory usage, 1 byte per 3D block.
+// Encode this with STBVOX_MAKE_VHEIGHT(vh_sw, vh_se, vh_nw, vh_ne).
+// These coordinates are absolute, not affected by block rotations.
+//
+// An alternative if you just want to encode some very specific block
+// types, not all the possibilities--say you just want half-height slopes,
+// so you want (0,0,1,1) and (1,1,2,2)--then you can use block_vheight
+// to specify them. The geometry rotation will cause block_vheight values
+// to be rotated (because it's as if you're just defining a type of
+// block). This value is also encoded with STBVOX_MAKE_VHEIGHT.
+//
+// If you want to save memory and you're creating a "continuous ground"
+// sort of effect, you can make each vertex of the lattice share the
+// vheight value; that is, two adjacent blocks that share a vertex will
+// always get the same vheight value for that vertex. Then you need to
+// store two bits of vheight for every block, which you do by storing it
+// as part another data structure. Store the south-west vertex's vheight
+// with the block. You can either use the "geometry" mesh variable (it's
+// a parameter to STBVOX_MAKE_GEOMETRY) or you can store it in the
+// "lighting" mesh variable if you defined STBVOX_CONFIG_VHEIGHT_IN_LIGHTING,
+// using STBVOX_MAKE_LIGHTING_EXT(lighting,vheight).
+//
+// Note that if you start with a 2D height map and generate vheight data from
+// it, you don't necessarily store only one value per (x,y) coordinate,
+// as the same value may need to be set up at multiple z heights. For
+// example, if height(8,8) = 13.5, then you want the block at (8,8,13)
+// to store STBVOX_VERTEX_HEIGHT_half, and this will be used by blocks
+// at (7,7,13), (8,7,13), (7,8,13), and (8,8,13). However, if you're
+// allowing steep slopes, it might be the case that you have a block
+// at (7,7,12) which is supposed to stick up to 13.5; that means
+// you also need to store STBVOX_VERTEX_HEIGHT_one_and_a_half at (8,8,12).
+
+enum
+{
+ STBVOX_TEXLERP_FACE_0,
+ STBVOX_TEXLERP_FACE_half,
+ STBVOX_TEXLERP_FACE_1,
+ STBVOX_TEXLERP_FACE_use_vert,
+};
+
+enum
+{
+ STBVOX_TEXLERP_BASE_0, // 0.0
+ STBVOX_TEXLERP_BASE_2_7, // 2/7
+ STBVOX_TEXLERP_BASE_5_7, // 4/7
+ STBVOX_TEXLERP_BASE_1 // 1.0
+};
+
+enum
+{
+ STBVOX_TEXLERP3_0_8,
+ STBVOX_TEXLERP3_1_8,
+ STBVOX_TEXLERP3_2_8,
+ STBVOX_TEXLERP3_3_8,
+ STBVOX_TEXLERP3_4_8,
+ STBVOX_TEXLERP3_5_8,
+ STBVOX_TEXLERP3_6_8,
+ STBVOX_TEXLERP3_7_8,
+};
+
+#define STBVOX_FACE_NONE 7
+
+#define STBVOX_BLOCKTYPE_EMPTY 0
+
+#ifdef STBVOX_BLOCKTYPE_SHORT
+#define STBVOX_BLOCKTYPE_HOLE 65535
+#else
+#define STBVOX_BLOCKTYPE_HOLE 255
+#endif
+
+#define STBVOX_MAKE_GEOMETRY(geom, rotate, vheight) ((geom) + (rotate)*16 + (vheight)*64)
+#define STBVOX_MAKE_VHEIGHT(v_sw, v_se, v_nw, v_ne) ((v_sw) + (v_se)*4 + (v_nw)*16 + (v_ne)*64)
+#define STBVOX_MAKE_MATROT(block, overlay, color) ((block) + (overlay)*4 + (color)*64)
+#define STBVOX_MAKE_TEX2_REPLACE(tex2, tex2_replace_face) ((tex2) + ((tex2_replace_face) & 3)*64)
+#define STBVOX_MAKE_TEXLERP(ns2, ew2, ud2, vert) ((ew2) + (ns2)*4 + (ud2)*16 + (vert)*64)
+#define STBVOX_MAKE_TEXLERP_SIMPLE(baselerp,vert,face) ((vert)*32 + (face)*4 + (baselerp))
+#define STBVOX_MAKE_TEXLERP1(vert,e2,n2,w2,s2,u4,d2) STBVOX_MAKE_TEXLERP(s2, w2, d2, vert)
+#define STBVOX_MAKE_TEXLERP2(vert,e2,n2,w2,s2,u4,d2) ((u2)*16 + (n2)*4 + (s2))
+#define STBVOX_MAKE_FACE_MASK(e,n,w,s,u,d) ((e)+(n)*2+(w)*4+(s)*8+(u)*16+(d)*32)
+#define STBVOX_MAKE_SIDE_TEXROT(e,n,w,s) ((e)+(n)*4+(w)*16+(s)*64)
+#define STBVOX_MAKE_COLOR(color,t1,t2) ((color)+(t1)*64+(t2)*128)
+#define STBVOX_MAKE_TEXLERP_VERT3(e,n,w,s,u) ((e)+(n)*8+(w)*64+(s)*512+(u)*4096)
+#define STBVOX_MAKE_TEXLERP_FACE3(e,n,w,s,u,d) ((e)+(n)*8+(w)*64+(s)*512+(u)*4096+(d)*16384)
+#define STBVOX_MAKE_PACKED_COMPACT(rot, vheight, texlerp, def) ((rot)+4*(vheight)+16*(use)+32*(texlerp))
+
+#define STBVOX_MAKE_LIGHTING_EXT(lighting, rot) (((lighting)&~3)+(rot))
+#define STBVOX_MAKE_LIGHTING(lighting) (lighting)
+
+#ifndef STBVOX_MAX_MESHES
+#define STBVOX_MAX_MESHES 2 // opaque & transparent
+#endif
+
+#define STBVOX_MAX_MESH_SLOTS 3 // one vertex & two faces, or two vertex and one face
+
+
+// don't mess with this directly, it's just here so you can
+// declare stbvox_mesh_maker on the stack or as a global
+struct stbvox_mesh_maker
+{
+ stbvox_input_description input;
+ int cur_x, cur_y, cur_z; // last unprocessed voxel if it splits into multiple buffers
+ int x0,y0,z0,x1,y1,z1;
+ int x_stride_in_bytes;
+ int y_stride_in_bytes;
+ int config_dirty;
+ int default_mesh;
+ unsigned int tags;
+
+ int cube_vertex_offset[6][4]; // this allows access per-vertex data stored block-centered (like texlerp, ambient)
+ int vertex_gather_offset[6][4];
+
+ int pos_x,pos_y,pos_z;
+ int full;
+
+ // computed from user input
+ char *output_cur [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS];
+ char *output_end [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS];
+ char *output_buffer[STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS];
+ int output_len [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS];
+
+ // computed from config
+ int output_size [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS]; // per quad
+ int output_step [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS]; // per vertex or per face, depending
+ int num_mesh_slots;
+
+ float default_tex_scale[128][2];
+};
+
+#endif // INCLUDE_STB_VOXEL_RENDER_H
+
+
+#ifdef STB_VOXEL_RENDER_IMPLEMENTATION
+
+#include <stdlib.h>
+#include <assert.h>
+#include <string.h> // memset
+
+// have to use our own names to avoid the _MSC_VER path having conflicting type names
+#ifndef _MSC_VER
+ #include <stdint.h>
+ typedef uint16_t stbvox_uint16;
+ typedef uint32_t stbvox_uint32;
+#else
+ typedef unsigned short stbvox_uint16;
+ typedef unsigned int stbvox_uint32;
+#endif
+
+#ifdef _MSC_VER
+ #define STBVOX_NOTUSED(v) (void)(v)
+#else
+ #define STBVOX_NOTUSED(v) (void)sizeof(v)
+#endif
+
+
+
+#ifndef STBVOX_CONFIG_MODE
+#error "Must defined STBVOX_CONFIG_MODE to select the mode"
+#endif
+
+#if defined(STBVOX_CONFIG_ROTATION_IN_LIGHTING) && defined(STBVOX_CONFIG_VHEIGHT_IN_LIGHTING)
+#error "Can't store both rotation and vheight in lighting"
+#endif
+
+
+// The following are candidate voxel modes. Only modes 0, 1, and 20, and 21 are
+// currently implemented. Reducing the storage-per-quad further
+// shouldn't improve performance, although obviously it allow you
+// to create larger worlds without streaming.
+//
+//
+// ----------- Two textures ----------- -- One texture -- ---- Color only ----
+// Mode: 0 1 2 3 4 5 6 10 11 12 20 21 22 23 24
+// ============================================================================================================
+// uses Tex Buffer n Y Y Y Y Y Y Y Y Y n Y Y Y Y
+// bytes per quad 32 20 14 12 10 6 6 8 8 4 32 20 10 6 4
+// non-blocks all all some some some slabs stairs some some none all all slabs slabs none
+// tex1 256 256 256 256 256 256 256 256 256 256 n n n n n
+// tex2 256 256 256 256 256 256 128 n n n n n n n n
+// colors 64 64 64 64 64 64 64 8 n n 2^24 2^24 2^24 2^24 256
+// vertex ao Y Y Y Y Y n n Y Y n Y Y Y n n
+// vertex texlerp Y Y Y n n n n - - - - - - - -
+// x&y extents 127 127 128 64 64 128 64 64 128 128 127 127 128 128 128
+// z extents 255 255 128 64? 64? 64 64 32 64 128 255 255 128 64 128
+
+// not sure why I only wrote down the above "result data" and didn't preserve
+// the vertex formats, but here I've tried to reconstruct the designs...
+// mode # 3 is wrong, one byte too large, but they may have been an error originally
+
+// Mode: 0 1 2 3 4 5 6 10 11 12 20 21 22 23 24
+// =============================================================================================================
+// bytes per quad 32 20 14 12 10 6 6 8 8 4 20 10 6 4
+//
+// vertex x bits 7 7 0 6 0 0 0 0 0 0 7 0 0 0
+// vertex y bits 7 7 0 0 0 0 0 0 0 0 7 0 0 0
+// vertex z bits 9 9 7 4 2 0 0 2 2 0 9 2 0 0
+// vertex ao bits 6 6 6 6 6 0 0 6 6 0 6 6 0 0
+// vertex txl bits 3 3 3 0 0 0 0 0 0 0 (3) 0 0 0
+//
+// face tex1 bits (8) 8 8 8 8 8 8 8 8 8
+// face tex2 bits (8) 8 8 8 8 8 7 - - -
+// face color bits (8) 8 8 8 8 8 8 3 0 0 24 24 24 8
+// face normal bits (8) 8 8 8 6 4 7 4 4 3 8 3 4 3
+// face x bits 7 0 6 7 6 6 7 7 0 7 7 7
+// face y bits 7 6 6 7 6 6 7 7 0 7 7 7
+// face z bits 2 2 6 6 6 5 6 7 0 7 6 7
+
+
+#if STBVOX_CONFIG_MODE==0 || STBVOX_CONFIG_MODE==1
+
+ #define STBVOX_ICONFIG_VERTEX_32
+ #define STBVOX_ICONFIG_FACE1_1
+
+#elif STBVOX_CONFIG_MODE==20 || STBVOX_CONFIG_MODE==21
+
+ #define STBVOX_ICONFIG_VERTEX_32
+ #define STBVOX_ICONFIG_FACE1_1
+ #define STBVOX_ICONFIG_UNTEXTURED
+
+#else
+#error "Selected value of STBVOX_CONFIG_MODE is not supported"
+#endif
+
+#if STBVOX_CONFIG_MODE==0 || STBVOX_CONFIG_MODE==20
+#define STBVOX_ICONFIG_FACE_ATTRIBUTE
+#endif
+
+#ifndef STBVOX_CONFIG_HLSL
+// the fallback if all others are exhausted is GLSL
+#define STBVOX_ICONFIG_GLSL
+#endif
+
+#ifdef STBVOX_CONFIG_OPENGL_MODELVIEW
+#define STBVOX_ICONFIG_OPENGL_3_1_COMPATIBILITY
+#endif
+
+#if defined(STBVOX_ICONFIG_VERTEX_32)
+ typedef stbvox_uint32 stbvox_mesh_vertex;
+ #define stbvox_vertex_encode(x,y,z,ao,texlerp) \
+ ((stbvox_uint32) ((x)+((y)<<7)+((z)<<14)+((ao)<<23)+((texlerp)<<29)))
+#elif defined(STBVOX_ICONFIG_VERTEX_16_1) // mode=2
+ typedef stbvox_uint16 stbvox_mesh_vertex;
+ #define stbvox_vertex_encode(x,y,z,ao,texlerp) \
+ ((stbvox_uint16) ((z)+((ao)<<7)+((texlerp)<<13)
+#elif defined(STBVOX_ICONFIG_VERTEX_16_2) // mode=3
+ typedef stbvox_uint16 stbvox_mesh_vertex;
+ #define stbvox_vertex_encode(x,y,z,ao,texlerp) \
+ ((stbvox_uint16) ((x)+((z)<<6))+((ao)<<10))
+#elif defined(STBVOX_ICONFIG_VERTEX_8)
+ typedef stbvox_uint8 stbvox_mesh_vertex;
+ #define stbvox_vertex_encode(x,y,z,ao,texlerp) \
+ ((stbvox_uint8) ((z)+((ao)<<6))
+#else
+ #error "internal error, no vertex type"
+#endif
+
+#ifdef STBVOX_ICONFIG_FACE1_1
+ typedef struct
+ {
+ unsigned char tex1,tex2,color,face_info;
+ } stbvox_mesh_face;
+#else
+ #error "internal error, no face type"
+#endif
+
+
+// 20-byte quad format:
+//
+// per vertex:
+//
+// x:7
+// y:7
+// z:9
+// ao:6
+// tex_lerp:3
+//
+// per face:
+//
+// tex1:8
+// tex2:8
+// face:8
+// color:8
+
+
+// Faces:
+//
+// Faces use the bottom 3 bits to choose the texgen
+// mode, and all the bits to choose the normal.
+// Thus the bottom 3 bits have to be:
+// e, n, w, s, u, d, u, d
+//
+// These use compact names so tables are readable
+
+enum
+{
+ STBVF_e,
+ STBVF_n,
+ STBVF_w,
+ STBVF_s,
+ STBVF_u,
+ STBVF_d,
+ STBVF_eu,
+ STBVF_ed,
+
+ STBVF_eu_wall,
+ STBVF_nu_wall,
+ STBVF_wu_wall,
+ STBVF_su_wall,
+ STBVF_ne_u,
+ STBVF_ne_d,
+ STBVF_nu,
+ STBVF_nd,
+
+ STBVF_ed_wall,
+ STBVF_nd_wall,
+ STBVF_wd_wall,
+ STBVF_sd_wall,
+ STBVF_nw_u,
+ STBVF_nw_d,
+ STBVF_wu,
+ STBVF_wd,
+
+ STBVF_ne_u_cross,
+ STBVF_nw_u_cross,
+ STBVF_sw_u_cross,
+ STBVF_se_u_cross,
+ STBVF_sw_u,
+ STBVF_sw_d,
+ STBVF_su,
+ STBVF_sd,
+
+ // @TODO we need more than 5 bits to encode the normal to fit the following
+ // so for now we use the right projection but the wrong normal
+ STBVF_se_u = STBVF_su,
+ STBVF_se_d = STBVF_sd,
+
+ STBVF_count,
+};
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// tables -- i'd prefer if these were at the end of the file, but: C++
+//
+
+static float stbvox_default_texgen[2][32][3] =
+{
+ { { 0, 1,0 }, { 0, 0, 1 }, { 0,-1,0 }, { 0, 0,-1 },
+ { -1, 0,0 }, { 0, 0, 1 }, { 1, 0,0 }, { 0, 0,-1 },
+ { 0,-1,0 }, { 0, 0, 1 }, { 0, 1,0 }, { 0, 0,-1 },
+ { 1, 0,0 }, { 0, 0, 1 }, { -1, 0,0 }, { 0, 0,-1 },
+
+ { 1, 0,0 }, { 0, 1, 0 }, { -1, 0,0 }, { 0,-1, 0 },
+ { -1, 0,0 }, { 0,-1, 0 }, { 1, 0,0 }, { 0, 1, 0 },
+ { 1, 0,0 }, { 0, 1, 0 }, { -1, 0,0 }, { 0,-1, 0 },
+ { -1, 0,0 }, { 0,-1, 0 }, { 1, 0,0 }, { 0, 1, 0 },
+ },
+ { { 0, 0,-1 }, { 0, 1,0 }, { 0, 0, 1 }, { 0,-1,0 },
+ { 0, 0,-1 }, { -1, 0,0 }, { 0, 0, 1 }, { 1, 0,0 },
+ { 0, 0,-1 }, { 0,-1,0 }, { 0, 0, 1 }, { 0, 1,0 },
+ { 0, 0,-1 }, { 1, 0,0 }, { 0, 0, 1 }, { -1, 0,0 },
+
+ { 0,-1, 0 }, { 1, 0,0 }, { 0, 1, 0 }, { -1, 0,0 },
+ { 0, 1, 0 }, { -1, 0,0 }, { 0,-1, 0 }, { 1, 0,0 },
+ { 0,-1, 0 }, { 1, 0,0 }, { 0, 1, 0 }, { -1, 0,0 },
+ { 0, 1, 0 }, { -1, 0,0 }, { 0,-1, 0 }, { 1, 0,0 },
+ },
+};
+
+#define STBVOX_RSQRT2 0.7071067811865f
+#define STBVOX_RSQRT3 0.5773502691896f
+
+static float stbvox_default_normals[32][3] =
+{
+ { 1,0,0 }, // east
+ { 0,1,0 }, // north
+ { -1,0,0 }, // west
+ { 0,-1,0 }, // south
+ { 0,0,1 }, // up
+ { 0,0,-1 }, // down
+ { STBVOX_RSQRT2,0, STBVOX_RSQRT2 }, // east & up
+ { STBVOX_RSQRT2,0, -STBVOX_RSQRT2 }, // east & down
+
+ { STBVOX_RSQRT2,0, STBVOX_RSQRT2 }, // east & up
+ { 0, STBVOX_RSQRT2, STBVOX_RSQRT2 }, // north & up
+ { -STBVOX_RSQRT2,0, STBVOX_RSQRT2 }, // west & up
+ { 0,-STBVOX_RSQRT2, STBVOX_RSQRT2 }, // south & up
+ { STBVOX_RSQRT3, STBVOX_RSQRT3, STBVOX_RSQRT3 }, // ne & up
+ { STBVOX_RSQRT3, STBVOX_RSQRT3,-STBVOX_RSQRT3 }, // ne & down
+ { 0, STBVOX_RSQRT2, STBVOX_RSQRT2 }, // north & up
+ { 0, STBVOX_RSQRT2, -STBVOX_RSQRT2 }, // north & down
+
+ { STBVOX_RSQRT2,0, -STBVOX_RSQRT2 }, // east & down
+ { 0, STBVOX_RSQRT2, -STBVOX_RSQRT2 }, // north & down
+ { -STBVOX_RSQRT2,0, -STBVOX_RSQRT2 }, // west & down
+ { 0,-STBVOX_RSQRT2, -STBVOX_RSQRT2 }, // south & down
+ { -STBVOX_RSQRT3, STBVOX_RSQRT3, STBVOX_RSQRT3 }, // NW & up
+ { -STBVOX_RSQRT3, STBVOX_RSQRT3,-STBVOX_RSQRT3 }, // NW & down
+ { -STBVOX_RSQRT2,0, STBVOX_RSQRT2 }, // west & up
+ { -STBVOX_RSQRT2,0, -STBVOX_RSQRT2 }, // west & down
+
+ { STBVOX_RSQRT3, STBVOX_RSQRT3,STBVOX_RSQRT3 }, // NE & up crossed
+ { -STBVOX_RSQRT3, STBVOX_RSQRT3,STBVOX_RSQRT3 }, // NW & up crossed
+ { -STBVOX_RSQRT3,-STBVOX_RSQRT3,STBVOX_RSQRT3 }, // SW & up crossed
+ { STBVOX_RSQRT3,-STBVOX_RSQRT3,STBVOX_RSQRT3 }, // SE & up crossed
+ { -STBVOX_RSQRT3,-STBVOX_RSQRT3, STBVOX_RSQRT3 }, // SW & up
+ { -STBVOX_RSQRT3,-STBVOX_RSQRT3,-STBVOX_RSQRT3 }, // SW & up
+ { 0,-STBVOX_RSQRT2, STBVOX_RSQRT2 }, // south & up
+ { 0,-STBVOX_RSQRT2, -STBVOX_RSQRT2 }, // south & down
+};
+
+static float stbvox_default_texscale[128][4] =
+{
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+ {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},
+};
+
+static unsigned char stbvox_default_palette_compact[64][3] =
+{
+ { 255,255,255 }, { 238,238,238 }, { 221,221,221 }, { 204,204,204 },
+ { 187,187,187 }, { 170,170,170 }, { 153,153,153 }, { 136,136,136 },
+ { 119,119,119 }, { 102,102,102 }, { 85, 85, 85 }, { 68, 68, 68 },
+ { 51, 51, 51 }, { 34, 34, 34 }, { 17, 17, 17 }, { 0, 0, 0 },
+ { 255,240,240 }, { 255,220,220 }, { 255,160,160 }, { 255, 32, 32 },
+ { 200,120,160 }, { 200, 60,150 }, { 220,100,130 }, { 255, 0,128 },
+ { 240,240,255 }, { 220,220,255 }, { 160,160,255 }, { 32, 32,255 },
+ { 120,160,200 }, { 60,150,200 }, { 100,130,220 }, { 0,128,255 },
+ { 240,255,240 }, { 220,255,220 }, { 160,255,160 }, { 32,255, 32 },
+ { 160,200,120 }, { 150,200, 60 }, { 130,220,100 }, { 128,255, 0 },
+ { 255,255,240 }, { 255,255,220 }, { 220,220,180 }, { 255,255, 32 },
+ { 200,160,120 }, { 200,150, 60 }, { 220,130,100 }, { 255,128, 0 },
+ { 255,240,255 }, { 255,220,255 }, { 220,180,220 }, { 255, 32,255 },
+ { 160,120,200 }, { 150, 60,200 }, { 130,100,220 }, { 128, 0,255 },
+ { 240,255,255 }, { 220,255,255 }, { 180,220,220 }, { 32,255,255 },
+ { 120,200,160 }, { 60,200,150 }, { 100,220,130 }, { 0,255,128 },
+};
+
+static float stbvox_default_ambient[4][4] =
+{
+ { 0,0,1 ,0 }, // reversed lighting direction
+ { 0.5,0.5,0.5,0 }, // directional color
+ { 0.5,0.5,0.5,0 }, // constant color
+ { 0.5,0.5,0.5,1.0f/1000.0f/1000.0f }, // fog data for simple_fog
+};
+
+static float stbvox_default_palette[64][4];
+
+static void stbvox_build_default_palette(void)
+{
+ int i;
+ for (i=0; i < 64; ++i) {
+ stbvox_default_palette[i][0] = stbvox_default_palette_compact[i][0] / 255.0f;
+ stbvox_default_palette[i][1] = stbvox_default_palette_compact[i][1] / 255.0f;
+ stbvox_default_palette[i][2] = stbvox_default_palette_compact[i][2] / 255.0f;
+ stbvox_default_palette[i][3] = 1.0f;
+ }
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Shaders
+//
+
+#if defined(STBVOX_ICONFIG_OPENGL_3_1_COMPATIBILITY)
+ #define STBVOX_SHADER_VERSION "#version 150 compatibility\n"
+#elif defined(STBVOX_ICONFIG_OPENGL_3_0)
+ #define STBVOX_SHADER_VERSION "#version 130\n"
+#elif defined(STBVOX_ICONFIG_GLSL)
+ #define STBVOX_SHADER_VERSION "#version 150\n"
+#else
+ #define STBVOX_SHADER_VERSION ""
+#endif
+
+static const char *stbvox_vertex_program =
+{
+ STBVOX_SHADER_VERSION
+
+ #ifdef STBVOX_ICONFIG_FACE_ATTRIBUTE // NOT TAG_face_sampled
+ "in uvec4 attr_face;\n"
+ #else
+ "uniform usamplerBuffer facearray;\n"
+ #endif
+
+ #ifdef STBVOX_ICONFIG_FACE_ARRAY_2
+ "uniform usamplerBuffer facearray2;\n"
+ #endif
+
+ // vertex input data
+ "in uint attr_vertex;\n"
+
+ // per-buffer data
+ "uniform vec3 transform[3];\n"
+
+ // per-frame data
+ "uniform vec4 camera_pos;\n" // 4th value is used for arbitrary hacking
+
+ // to simplify things, we avoid using more than 256 uniform vectors
+ // in fragment shader to avoid possible 1024 component limit, so
+ // we access this table in the fragment shader.
+ "uniform vec3 normal_table[32];\n"
+
+ #ifndef STBVOX_CONFIG_OPENGL_MODELVIEW
+ "uniform mat4x4 model_view;\n"
+ #endif
+
+ // fragment output data
+ "flat out uvec4 facedata;\n"
+ " out vec3 voxelspace_pos;\n"
+ " out vec3 vnormal;\n"
+ " out float texlerp;\n"
+ " out float amb_occ;\n"
+
+ // @TODO handle the HLSL way to do this
+ "void main()\n"
+ "{\n"
+ #ifdef STBVOX_ICONFIG_FACE_ATTRIBUTE
+ " facedata = attr_face;\n"
+ #else
+ " int faceID = gl_VertexID >> 2;\n"
+ " facedata = texelFetch(facearray, faceID);\n"
+ #endif
+
+ // extract data for vertex
+ " vec3 offset;\n"
+ " offset.x = float( (attr_vertex ) & 127u );\n" // a[0..6]
+ " offset.y = float( (attr_vertex >> 7u) & 127u );\n" // a[7..13]
+ " offset.z = float( (attr_vertex >> 14u) & 511u );\n" // a[14..22]
+ " amb_occ = float( (attr_vertex >> 23u) & 63u ) / 63.0;\n" // a[23..28]
+ " texlerp = float( (attr_vertex >> 29u) ) / 7.0;\n" // a[29..31]
+
+ " vnormal = normal_table[(facedata.w>>2u) & 31u];\n"
+ " voxelspace_pos = offset * transform[0];\n" // mesh-to-object scale
+ " vec3 position = voxelspace_pos + transform[1];\n" // mesh-to-object translate
+
+ #ifdef STBVOX_DEBUG_TEST_NORMALS
+ " if ((facedata.w & 28u) == 16u || (facedata.w & 28u) == 24u)\n"
+ " position += vnormal.xyz * camera_pos.w;\n"
+ #endif
+
+ #ifndef STBVOX_CONFIG_OPENGL_MODELVIEW
+ " gl_Position = model_view * vec4(position,1.0);\n"
+ #else
+ " gl_Position = gl_ModelViewProjectionMatrix * vec4(position,1.0);\n"
+ #endif
+
+ "}\n"
+};
+
+
+static const char *stbvox_fragment_program =
+{
+ STBVOX_SHADER_VERSION
+
+ // rlerp is lerp but with t on the left, like god intended
+ #if defined(STBVOX_ICONFIG_GLSL)
+ "#define rlerp(t,x,y) mix(x,y,t)\n"
+ #elif defined(STBVOX_CONFIG_HLSL)
+ "#define rlerp(t,x,y) lerp(x,y,t)\n"
+ #else
+ #error "need definition of rlerp()"
+ #endif
+
+
+ // vertex-shader output data
+ "flat in uvec4 facedata;\n"
+ " in vec3 voxelspace_pos;\n"
+ " in vec3 vnormal;\n"
+ " in float texlerp;\n"
+ " in float amb_occ;\n"
+
+ // per-buffer data
+ "uniform vec3 transform[3];\n"
+
+ // per-frame data
+ "uniform vec4 camera_pos;\n" // 4th value is used for arbitrary hacking
+
+ // probably constant data
+ "uniform vec4 ambient[4];\n"
+
+ #ifndef STBVOX_ICONFIG_UNTEXTURED
+ // generally constant data
+ "uniform sampler2DArray tex_array[2];\n"
+
+ #ifdef STBVOX_CONFIG_PREFER_TEXBUFFER
+ "uniform samplerBuffer color_table;\n"
+ "uniform samplerBuffer texscale;\n"
+ "uniform samplerBuffer texgen;\n"
+ #else
+ "uniform vec4 color_table[64];\n"
+ "uniform vec4 texscale[64];\n" // instead of 128, to avoid running out of uniforms
+ "uniform vec3 texgen[64];\n"
+ #endif
+ #endif
+
+ "out vec4 outcolor;\n"
+
+ #if defined(STBVOX_CONFIG_LIGHTING) || defined(STBVOX_CONFIG_LIGHTING_SIMPLE)
+ "vec3 compute_lighting(vec3 pos, vec3 norm, vec3 albedo, vec3 ambient);\n"
+ #endif
+ #if defined(STBVOX_CONFIG_FOG) || defined(STBVOX_CONFIG_FOG_SMOOTHSTEP)
+ "vec3 compute_fog(vec3 color, vec3 relative_pos, float fragment_alpha);\n"
+ #endif
+
+ "void main()\n"
+ "{\n"
+ " vec3 albedo;\n"
+ " float fragment_alpha;\n"
+
+ #ifndef STBVOX_ICONFIG_UNTEXTURED
+ // unpack the values
+ " uint tex1_id = facedata.x;\n"
+ " uint tex2_id = facedata.y;\n"
+ " uint texprojid = facedata.w & 31u;\n"
+ " uint color_id = facedata.z;\n"
+
+ #ifndef STBVOX_CONFIG_PREFER_TEXBUFFER
+ // load from uniforms / texture buffers
+ " vec3 texgen_s = texgen[texprojid];\n"
+ " vec3 texgen_t = texgen[texprojid+32u];\n"
+ " float tex1_scale = texscale[tex1_id & 63u].x;\n"
+ " vec4 color = color_table[color_id & 63u];\n"
+ #ifndef STBVOX_CONFIG_DISABLE_TEX2
+ " vec4 tex2_props = texscale[tex2_id & 63u];\n"
+ #endif
+ #else
+ " vec3 texgen_s = texelFetch(texgen, int(texprojid)).xyz;\n"
+ " vec3 texgen_t = texelFetch(texgen, int(texprojid+32u)).xyz;\n"
+ " float tex1_scale = texelFetch(texscale, int(tex1_id & 127u)).x;\n"
+ " vec4 color = texelFetch(color_table, int(color_id & 63u));\n"
+ #ifndef STBVOX_CONFIG_DISABLE_TEX2
+ " vec4 tex2_props = texelFetch(texscale, int(tex1_id & 127u));\n"
+ #endif
+ #endif
+
+ #ifndef STBVOX_CONFIG_DISABLE_TEX2
+ " float tex2_scale = tex2_props.y;\n"
+ " bool texblend_mode = tex2_props.z != 0.0;\n"
+ #endif
+ " vec2 texcoord;\n"
+ " vec3 texturespace_pos = voxelspace_pos + transform[2].xyz;\n"
+ " texcoord.s = dot(texturespace_pos, texgen_s);\n"
+ " texcoord.t = dot(texturespace_pos, texgen_t);\n"
+
+ " vec2 texcoord_1 = tex1_scale * texcoord;\n"
+ #ifndef STBVOX_CONFIG_DISABLE_TEX2
+ " vec2 texcoord_2 = tex2_scale * texcoord;\n"
+ #endif
+
+ #ifdef STBVOX_CONFIG_TEX1_EDGE_CLAMP
+ " texcoord_1 = texcoord_1 - floor(texcoord_1);\n"
+ " vec4 tex1 = textureGrad(tex_array[0], vec3(texcoord_1, float(tex1_id)), dFdx(tex1_scale*texcoord), dFdy(tex1_scale*texcoord));\n"
+ #else
+ " vec4 tex1 = texture(tex_array[0], vec3(texcoord_1, float(tex1_id)));\n"
+ #endif
+
+ #ifndef STBVOX_CONFIG_DISABLE_TEX2
+ #ifdef STBVOX_CONFIG_TEX2_EDGE_CLAMP
+ " texcoord_2 = texcoord_2 - floor(texcoord_2);\n"
+ " vec4 tex2 = textureGrad(tex_array[0], vec3(texcoord_2, float(tex2_id)), dFdx(tex2_scale*texcoord), dFdy(tex2_scale*texcoord));\n"
+ #else
+ " vec4 tex2 = texture(tex_array[1], vec3(texcoord_2, float(tex2_id)));\n"
+ #endif
+ #endif
+
+ " bool emissive = (color.a > 1.0);\n"
+ " color.a = min(color.a, 1.0);\n"
+
+ // recolor textures
+ " if ((color_id & 64u) != 0u) tex1.rgba *= color.rgba;\n"
+ " fragment_alpha = tex1.a;\n"
+ #ifndef STBVOX_CONFIG_DISABLE_TEX2
+ " if ((color_id & 128u) != 0u) tex2.rgba *= color.rgba;\n"
+
+ #ifdef STBVOX_CONFIG_PREMULTIPLIED_ALPHA
+ " tex2.rgba *= texlerp;\n"
+ #else
+ " tex2.a *= texlerp;\n"
+ #endif
+
+ " if (texblend_mode)\n"
+ " albedo = tex1.xyz * rlerp(tex2.a, vec3(1.0,1.0,1.0), 2.0*tex2.xyz);\n"
+ " else {\n"
+ #ifdef STBVOX_CONFIG_PREMULTIPLIED_ALPHA
+ " albedo = (1.0-tex2.a)*tex1.xyz + tex2.xyz;\n"
+ #else
+ " albedo = rlerp(tex2.a, tex1.xyz, tex2.xyz);\n"
+ #endif
+ " fragment_alpha = tex1.a*(1-tex2.a)+tex2.a;\n"
+ " }\n"
+ #else
+ " albedo = tex1.xyz;\n"
+ #endif
+
+ #else // UNTEXTURED
+ " vec4 color;"
+ " color.xyz = vec3(facedata.xyz) / 255.0;\n"
+ " bool emissive = false;\n"
+ " albedo = color.xyz;\n"
+ " fragment_alpha = 1.0;\n"
+ #endif
+
+ #ifdef STBVOX_ICONFIG_VARYING_VERTEX_NORMALS
+ // currently, there are no modes that trigger this path; idea is that there
+ // could be a couple of bits per vertex to perturb the normal to e.g. get curved look
+ " vec3 normal = normalize(vnormal);\n"
+ #else
+ " vec3 normal = vnormal;\n"
+ #endif
+
+ " vec3 ambient_color = dot(normal, ambient[0].xyz) * ambient[1].xyz + ambient[2].xyz;\n"
+
+ " ambient_color = clamp(ambient_color, 0.0, 1.0);"
+ " ambient_color *= amb_occ;\n"
+
+ " vec3 lit_color;\n"
+ " if (!emissive)\n"
+ #if defined(STBVOX_ICONFIG_LIGHTING) || defined(STBVOX_CONFIG_LIGHTING_SIMPLE)
+ " lit_color = compute_lighting(voxelspace_pos + transform[1], normal, albedo, ambient_color);\n"
+ #else
+ " lit_color = albedo * ambient_color ;\n"
+ #endif
+ " else\n"
+ " lit_color = albedo;\n"
+
+ #if defined(STBVOX_ICONFIG_FOG) || defined(STBVOX_CONFIG_FOG_SMOOTHSTEP)
+ " vec3 dist = voxelspace_pos + (transform[1] - camera_pos.xyz);\n"
+ " lit_color = compute_fog(lit_color, dist, fragment_alpha);\n"
+ #endif
+
+ #ifdef STBVOX_CONFIG_UNPREMULTIPLY
+ " vec4 final_color = vec4(lit_color/fragment_alpha, fragment_alpha);\n"
+ #else
+ " vec4 final_color = vec4(lit_color, fragment_alpha);\n"
+ #endif
+ " outcolor = final_color;\n"
+ "}\n"
+
+ #ifdef STBVOX_CONFIG_LIGHTING_SIMPLE
+ "\n"
+ "uniform vec3 light_source[2];\n"
+ "vec3 compute_lighting(vec3 pos, vec3 norm, vec3 albedo, vec3 ambient)\n"
+ "{\n"
+ " vec3 light_dir = light_source[0] - pos;\n"
+ " float lambert = dot(light_dir, norm) / dot(light_dir, light_dir);\n"
+ " vec3 diffuse = clamp(light_source[1] * clamp(lambert, 0.0, 1.0), 0.0, 1.0);\n"
+ " return (diffuse + ambient) * albedo;\n"
+ "}\n"
+ #endif
+
+ #ifdef STBVOX_CONFIG_FOG_SMOOTHSTEP
+ "\n"
+ "vec3 compute_fog(vec3 color, vec3 relative_pos, float fragment_alpha)\n"
+ "{\n"
+ " float f = dot(relative_pos,relative_pos)*ambient[3].w;\n"
+ //" f = rlerp(f, -2,1);\n"
+ " f = clamp(f, 0.0, 1.0);\n"
+ " f = 3.0*f*f - 2.0*f*f*f;\n" // smoothstep
+ //" f = f*f;\n" // fade in more smoothly
+ #ifdef STBVOX_CONFIG_PREMULTIPLIED_ALPHA
+ " return rlerp(f, color.xyz, ambient[3].xyz*fragment_alpha);\n"
+ #else
+ " return rlerp(f, color.xyz, ambient[3].xyz);\n"
+ #endif
+ "}\n"
+ #endif
+};
+
+
+// still requires full alpha lookups, including tex2 if texblend is enabled
+static const char *stbvox_fragment_program_alpha_only =
+{
+ STBVOX_SHADER_VERSION
+
+ // vertex-shader output data
+ "flat in uvec4 facedata;\n"
+ " in vec3 voxelspace_pos;\n"
+ " in float texlerp;\n"
+
+ // per-buffer data
+ "uniform vec3 transform[3];\n"
+
+ #ifndef STBVOX_ICONFIG_UNTEXTURED
+ // generally constant data
+ "uniform sampler2DArray tex_array[2];\n"
+
+ #ifdef STBVOX_CONFIG_PREFER_TEXBUFFER
+ "uniform samplerBuffer texscale;\n"
+ "uniform samplerBuffer texgen;\n"
+ #else
+ "uniform vec4 texscale[64];\n" // instead of 128, to avoid running out of uniforms
+ "uniform vec3 texgen[64];\n"
+ #endif
+ #endif
+
+ "out vec4 outcolor;\n"
+
+ "void main()\n"
+ "{\n"
+ " vec3 albedo;\n"
+ " float fragment_alpha;\n"
+
+ #ifndef STBVOX_ICONFIG_UNTEXTURED
+ // unpack the values
+ " uint tex1_id = facedata.x;\n"
+ " uint tex2_id = facedata.y;\n"
+ " uint texprojid = facedata.w & 31u;\n"
+ " uint color_id = facedata.z;\n"
+
+ #ifndef STBVOX_CONFIG_PREFER_TEXBUFFER
+ // load from uniforms / texture buffers
+ " vec3 texgen_s = texgen[texprojid];\n"
+ " vec3 texgen_t = texgen[texprojid+32u];\n"
+ " float tex1_scale = texscale[tex1_id & 63u].x;\n"
+ " vec4 color = color_table[color_id & 63u];\n"
+ " vec4 tex2_props = texscale[tex2_id & 63u];\n"
+ #else
+ " vec3 texgen_s = texelFetch(texgen, int(texprojid)).xyz;\n"
+ " vec3 texgen_t = texelFetch(texgen, int(texprojid+32u)).xyz;\n"
+ " float tex1_scale = texelFetch(texscale, int(tex1_id & 127u)).x;\n"
+ " vec4 color = texelFetch(color_table, int(color_id & 63u));\n"
+ " vec4 tex2_props = texelFetch(texscale, int(tex2_id & 127u));\n"
+ #endif
+
+ #ifndef STBVOX_CONFIG_DISABLE_TEX2
+ " float tex2_scale = tex2_props.y;\n"
+ " bool texblend_mode = tex2_props.z &((facedata.w & 128u) != 0u);\n"
+ #endif
+
+ " color.a = min(color.a, 1.0);\n"
+
+ " vec2 texcoord;\n"
+ " vec3 texturespace_pos = voxelspace_pos + transform[2].xyz;\n"
+ " texcoord.s = dot(texturespace_pos, texgen_s);\n"
+ " texcoord.t = dot(texturespace_pos, texgen_t);\n"
+
+ " vec2 texcoord_1 = tex1_scale * texcoord;\n"
+ " vec2 texcoord_2 = tex2_scale * texcoord;\n"
+
+ #ifdef STBVOX_CONFIG_TEX1_EDGE_CLAMP
+ " texcoord_1 = texcoord_1 - floor(texcoord_1);\n"
+ " vec4 tex1 = textureGrad(tex_array[0], vec3(texcoord_1, float(tex1_id)), dFdx(tex1_scale*texcoord), dFdy(tex1_scale*texcoord));\n"
+ #else
+ " vec4 tex1 = texture(tex_array[0], vec3(texcoord_1, float(tex1_id)));\n"
+ #endif
+
+ " if ((color_id & 64u) != 0u) tex1.a *= color.a;\n"
+ " fragment_alpha = tex1.a;\n"
+
+ #ifndef STBVOX_CONFIG_DISABLE_TEX2
+ " if (!texblend_mode) {\n"
+ #ifdef STBVOX_CONFIG_TEX2_EDGE_CLAMP
+ " texcoord_2 = texcoord_2 - floor(texcoord_2);\n"
+ " vec4 tex2 = textureGrad(tex_array[0], vec3(texcoord_2, float(tex2_id)), dFdx(tex2_scale*texcoord), dFdy(tex2_scale*texcoord));\n"
+ #else
+ " vec4 tex2 = texture(tex_array[1], vec3(texcoord_2, float(tex2_id)));\n"
+ #endif
+
+ " tex2.a *= texlerp;\n"
+ " if ((color_id & 128u) != 0u) tex2.rgba *= color.a;\n"
+ " fragment_alpha = tex1.a*(1-tex2.a)+tex2.a;\n"
+ "}\n"
+ "\n"
+ #endif
+
+ #else // UNTEXTURED
+ " fragment_alpha = 1.0;\n"
+ #endif
+
+ " outcolor = vec4(0.0, 0.0, 0.0, fragment_alpha);\n"
+ "}\n"
+};
+
+
+STBVXDEC char *stbvox_get_vertex_shader(void)
+{
+ return (char *) stbvox_vertex_program;
+}
+
+STBVXDEC char *stbvox_get_fragment_shader(void)
+{
+ return (char *) stbvox_fragment_program;
+}
+
+STBVXDEC char *stbvox_get_fragment_shader_alpha_only(void)
+{
+ return (char *) stbvox_fragment_program_alpha_only;
+}
+
+static float stbvox_dummy_transform[3][3];
+
+#ifdef STBVOX_CONFIG_PREFER_TEXBUFFER
+#define STBVOX_TEXBUF 1
+#else
+#define STBVOX_TEXBUF 0
+#endif
+
+static stbvox_uniform_info stbvox_uniforms[] =
+{
+ { STBVOX_UNIFORM_TYPE_sampler , 4, 1, (char*) "facearray" , 0 },
+ { STBVOX_UNIFORM_TYPE_vec3 , 12, 3, (char*) "transform" , stbvox_dummy_transform[0] },
+ { STBVOX_UNIFORM_TYPE_sampler , 4, 2, (char*) "tex_array" , 0 },
+ { STBVOX_UNIFORM_TYPE_vec4 , 16, 128, (char*) "texscale" , stbvox_default_texscale[0] , STBVOX_TEXBUF },
+ { STBVOX_UNIFORM_TYPE_vec4 , 16, 64, (char*) "color_table" , stbvox_default_palette[0] , STBVOX_TEXBUF },
+ { STBVOX_UNIFORM_TYPE_vec3 , 12, 32, (char*) "normal_table" , stbvox_default_normals[0] },
+ { STBVOX_UNIFORM_TYPE_vec3 , 12, 64, (char*) "texgen" , stbvox_default_texgen[0][0], STBVOX_TEXBUF },
+ { STBVOX_UNIFORM_TYPE_vec4 , 16, 4, (char*) "ambient" , stbvox_default_ambient[0] },
+ { STBVOX_UNIFORM_TYPE_vec4 , 16, 1, (char*) "camera_pos" , stbvox_dummy_transform[0] },
+};
+
+STBVXDEC int stbvox_get_uniform_info(stbvox_uniform_info *info, int uniform)
+{
+ if (uniform < 0 || uniform >= STBVOX_UNIFORM_count)
+ return 0;
+
+ *info = stbvox_uniforms[uniform];
+ return 1;
+}
+
+#define STBVOX_GET_GEO(geom_data) ((geom_data) & 15)
+
+typedef struct
+{
+ unsigned char block:2;
+ unsigned char overlay:2;
+ unsigned char facerot:2;
+ unsigned char ecolor:2;
+} stbvox_rotate;
+
+typedef struct
+{
+ unsigned char x,y,z;
+} stbvox_pos;
+
+static unsigned char stbvox_rotate_face[6][4] =
+{
+ { 0,1,2,3 },
+ { 1,2,3,0 },
+ { 2,3,0,1 },
+ { 3,0,1,2 },
+ { 4,4,4,4 },
+ { 5,5,5,5 },
+};
+
+#define STBVOX_ROTATE(x,r) stbvox_rotate_face[x][r] // (((x)+(r))&3)
+
+stbvox_mesh_face stbvox_compute_mesh_face_value(stbvox_mesh_maker *mm, stbvox_rotate rot, int face, int v_off, int normal)
+{
+ stbvox_mesh_face face_data = { 0 };
+ stbvox_block_type bt = mm->input.blocktype[v_off];
+ unsigned char bt_face = STBVOX_ROTATE(face, rot.block);
+ int facerot = rot.facerot;
+
+ #ifdef STBVOX_ICONFIG_UNTEXTURED
+ if (mm->input.rgb) {
+ face_data.tex1 = mm->input.rgb[v_off].r;
+ face_data.tex2 = mm->input.rgb[v_off].g;
+ face_data.color = mm->input.rgb[v_off].b;
+ face_data.face_info = (normal<<2);
+ return face_data;
+ }
+ #else
+ unsigned char color_face;
+
+ if (mm->input.color)
+ face_data.color = mm->input.color[v_off];
+
+ if (mm->input.block_tex1)
+ face_data.tex1 = mm->input.block_tex1[bt];
+ else if (mm->input.block_tex1_face)
+ face_data.tex1 = mm->input.block_tex1_face[bt][bt_face];
+ else
+ face_data.tex1 = bt;
+
+ if (mm->input.block_tex2)
+ face_data.tex2 = mm->input.block_tex2[bt];
+ else if (mm->input.block_tex2_face)
+ face_data.tex2 = mm->input.block_tex2_face[bt][bt_face];
+
+ if (mm->input.block_color) {
+ unsigned char mcol = mm->input.block_color[bt];
+ if (mcol)
+ face_data.color = mcol;
+ } else if (mm->input.block_color_face) {
+ unsigned char mcol = mm->input.block_color_face[bt][bt_face];
+ if (mcol)
+ face_data.color = mcol;
+ }
+
+ if (face <= STBVOX_FACE_south) {
+ if (mm->input.side_texrot)
+ facerot = mm->input.side_texrot[v_off] >> (2 * face);
+ else if (mm->input.block_side_texrot)
+ facerot = mm->input.block_side_texrot[v_off] >> (2 * bt_face);
+ }
+
+ if (mm->input.overlay) {
+ int over_face = STBVOX_ROTATE(face, rot.overlay);
+ unsigned char over = mm->input.overlay[v_off];
+ if (over) {
+ if (mm->input.overlay_tex1) {
+ unsigned char rep1 = mm->input.overlay_tex1[over][over_face];
+ if (rep1)
+ face_data.tex1 = rep1;
+ }
+ if (mm->input.overlay_tex2) {
+ unsigned char rep2 = mm->input.overlay_tex2[over][over_face];
+ if (rep2)
+ face_data.tex2 = rep2;
+ }
+ if (mm->input.overlay_color) {
+ unsigned char rep3 = mm->input.overlay_color[over][over_face];
+ if (rep3)
+ face_data.color = rep3;
+ }
+
+ if (mm->input.overlay_side_texrot && face <= STBVOX_FACE_south)
+ facerot = mm->input.overlay_side_texrot[over] >> (2*over_face);
+ }
+ }
+
+ if (mm->input.tex2_for_tex1)
+ face_data.tex2 = mm->input.tex2_for_tex1[face_data.tex1];
+ if (mm->input.tex2)
+ face_data.tex2 = mm->input.tex2[v_off];
+ if (mm->input.tex2_replace) {
+ if (mm->input.tex2_facemask[v_off] & (1 << face))
+ face_data.tex2 = mm->input.tex2_replace[v_off];
+ }
+
+ color_face = STBVOX_ROTATE(face, rot.ecolor);
+ if (mm->input.extended_color) {
+ unsigned char ec = mm->input.extended_color[v_off];
+ if (mm->input.ecolor_facemask[ec] & (1 << color_face))
+ face_data.color = mm->input.ecolor_color[ec];
+ }
+
+ if (mm->input.color2) {
+ if (mm->input.color2_facemask[v_off] & (1 << color_face))
+ face_data.color = mm->input.color2[v_off];
+ if (mm->input.color3 && (mm->input.color3_facemask[v_off] & (1 << color_face)))
+ face_data.color = mm->input.color3[v_off];
+ }
+ #endif
+
+ face_data.face_info = (normal<<2) + facerot;
+ return face_data;
+}
+
+// these are the types of faces each block can have
+enum
+{
+ STBVOX_FT_none ,
+ STBVOX_FT_upper ,
+ STBVOX_FT_lower ,
+ STBVOX_FT_solid ,
+ STBVOX_FT_diag_012,
+ STBVOX_FT_diag_023,
+ STBVOX_FT_diag_013,
+ STBVOX_FT_diag_123,
+ STBVOX_FT_force , // can't be covered up, used for internal faces, also hides nothing
+ STBVOX_FT_partial , // only covered by solid, never covers anything else
+
+ STBVOX_FT_count
+};
+
+static unsigned char stbvox_face_lerp[6] = { 0,2,0,2,4,4 };
+static unsigned char stbvox_vert3_lerp[5] = { 0,3,6,9,12 };
+static unsigned char stbvox_vert_lerp_for_face_lerp[4] = { 0, 4, 7, 7 };
+static unsigned char stbvox_face3_lerp[6] = { 0,3,6,9,12,14 };
+static unsigned char stbvox_vert_lerp_for_simple[4] = { 0,2,5,7 };
+static unsigned char stbvox_face3_updown[8] = { 0,2,5,7,0,2,5,7 }; // ignore top bit
+
+// vertex offsets for face vertices
+static unsigned char stbvox_vertex_vector[6][4][3] =
+{
+ { { 1,0,1 }, { 1,1,1 }, { 1,1,0 }, { 1,0,0 } }, // east
+ { { 1,1,1 }, { 0,1,1 }, { 0,1,0 }, { 1,1,0 } }, // north
+ { { 0,1,1 }, { 0,0,1 }, { 0,0,0 }, { 0,1,0 } }, // west
+ { { 0,0,1 }, { 1,0,1 }, { 1,0,0 }, { 0,0,0 } }, // south
+ { { 0,1,1 }, { 1,1,1 }, { 1,0,1 }, { 0,0,1 } }, // up
+ { { 0,0,0 }, { 1,0,0 }, { 1,1,0 }, { 0,1,0 } }, // down
+};
+
+// stbvox_vertex_vector, but read coordinates as binary numbers, zyx
+static unsigned char stbvox_vertex_selector[6][4] =
+{
+ { 5,7,3,1 },
+ { 7,6,2,3 },
+ { 6,4,0,2 },
+ { 4,5,1,0 },
+ { 6,7,5,4 },
+ { 0,1,3,2 },
+};
+
+static stbvox_mesh_vertex stbvox_vmesh_delta_normal[6][4] =
+{
+ { stbvox_vertex_encode(1,0,1,0,0) ,
+ stbvox_vertex_encode(1,1,1,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) },
+ { stbvox_vertex_encode(1,1,1,0,0) ,
+ stbvox_vertex_encode(0,1,1,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) },
+ { stbvox_vertex_encode(0,1,1,0,0) ,
+ stbvox_vertex_encode(0,0,1,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) },
+ { stbvox_vertex_encode(0,0,1,0,0) ,
+ stbvox_vertex_encode(1,0,1,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) },
+ { stbvox_vertex_encode(0,1,1,0,0) ,
+ stbvox_vertex_encode(1,1,1,0,0) ,
+ stbvox_vertex_encode(1,0,1,0,0) ,
+ stbvox_vertex_encode(0,0,1,0,0) },
+ { stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) }
+};
+
+static stbvox_mesh_vertex stbvox_vmesh_pre_vheight[6][4] =
+{
+ { stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) },
+ { stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) },
+ { stbvox_vertex_encode(0,1,0,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) },
+ { stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) },
+ { stbvox_vertex_encode(0,1,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) },
+ { stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) }
+};
+
+static stbvox_mesh_vertex stbvox_vmesh_delta_half_z[6][4] =
+{
+ { stbvox_vertex_encode(1,0,2,0,0) ,
+ stbvox_vertex_encode(1,1,2,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) },
+ { stbvox_vertex_encode(1,1,2,0,0) ,
+ stbvox_vertex_encode(0,1,2,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) },
+ { stbvox_vertex_encode(0,1,2,0,0) ,
+ stbvox_vertex_encode(0,0,2,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) },
+ { stbvox_vertex_encode(0,0,2,0,0) ,
+ stbvox_vertex_encode(1,0,2,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) },
+ { stbvox_vertex_encode(0,1,2,0,0) ,
+ stbvox_vertex_encode(1,1,2,0,0) ,
+ stbvox_vertex_encode(1,0,2,0,0) ,
+ stbvox_vertex_encode(0,0,2,0,0) },
+ { stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) }
+};
+
+static stbvox_mesh_vertex stbvox_vmesh_crossed_pair[6][4] =
+{
+ { stbvox_vertex_encode(1,0,2,0,0) ,
+ stbvox_vertex_encode(0,1,2,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) },
+ { stbvox_vertex_encode(1,1,2,0,0) ,
+ stbvox_vertex_encode(0,0,2,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) },
+ { stbvox_vertex_encode(0,1,2,0,0) ,
+ stbvox_vertex_encode(1,0,2,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) },
+ { stbvox_vertex_encode(0,0,2,0,0) ,
+ stbvox_vertex_encode(1,1,2,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(0,0,0,0,0) },
+ // not used, so we leave it non-degenerate to make sure it doesn't get gen'd accidentally
+ { stbvox_vertex_encode(0,1,2,0,0) ,
+ stbvox_vertex_encode(1,1,2,0,0) ,
+ stbvox_vertex_encode(1,0,2,0,0) ,
+ stbvox_vertex_encode(0,0,2,0,0) },
+ { stbvox_vertex_encode(0,0,0,0,0) ,
+ stbvox_vertex_encode(1,0,0,0,0) ,
+ stbvox_vertex_encode(1,1,0,0,0) ,
+ stbvox_vertex_encode(0,1,0,0,0) }
+};
+
+#define STBVOX_MAX_GEOM 16
+#define STBVOX_NUM_ROTATION 4
+
+// this is used to determine if a face is ever generated at all
+static unsigned char stbvox_hasface[STBVOX_MAX_GEOM][STBVOX_NUM_ROTATION] =
+{
+ { 0,0,0,0 }, // empty
+ { 0,0,0,0 }, // knockout
+ { 63,63,63,63 }, // solid
+ { 63,63,63,63 }, // transp
+ { 63,63,63,63 }, // slab
+ { 63,63,63,63 }, // slab
+ { 1|2|4|48, 8|1|2|48, 4|8|1|48, 2|4|8|48, }, // floor slopes
+ { 1|2|4|48, 8|1|2|48, 4|8|1|48, 2|4|8|48, }, // ceil slopes
+ { 47,47,47,47 }, // wall-projected diagonal with down face
+ { 31,31,31,31 }, // wall-projected diagonal with up face
+ { 63,63,63,63 }, // crossed-pair has special handling, but avoid early-out
+ { 63,63,63,63 }, // force
+ { 63,63,63,63 }, // vheight
+ { 63,63,63,63 }, // vheight
+ { 63,63,63,63 }, // vheight
+ { 63,63,63,63 }, // vheight
+};
+
+// this determines which face type above is visible on each side of the geometry
+static unsigned char stbvox_facetype[STBVOX_GEOM_count][6] =
+{
+ { 0, }, // STBVOX_GEOM_empty
+ { STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid }, // knockout
+ { STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid }, // solid
+ { STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force }, // transp
+
+ { STBVOX_FT_upper, STBVOX_FT_upper, STBVOX_FT_upper, STBVOX_FT_upper, STBVOX_FT_solid, STBVOX_FT_force },
+ { STBVOX_FT_lower, STBVOX_FT_lower, STBVOX_FT_lower, STBVOX_FT_lower, STBVOX_FT_force, STBVOX_FT_solid },
+ { STBVOX_FT_diag_123, STBVOX_FT_solid, STBVOX_FT_diag_023, STBVOX_FT_none, STBVOX_FT_force, STBVOX_FT_solid },
+ { STBVOX_FT_diag_012, STBVOX_FT_solid, STBVOX_FT_diag_013, STBVOX_FT_none, STBVOX_FT_solid, STBVOX_FT_force },
+
+ { STBVOX_FT_diag_123, STBVOX_FT_solid, STBVOX_FT_diag_023, STBVOX_FT_force, STBVOX_FT_none, STBVOX_FT_solid },
+ { STBVOX_FT_diag_012, STBVOX_FT_solid, STBVOX_FT_diag_013, STBVOX_FT_force, STBVOX_FT_solid, STBVOX_FT_none },
+ { STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, 0,0 }, // crossed pair
+ { STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force }, // GEOM_force
+
+ { STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial, STBVOX_FT_force, STBVOX_FT_solid }, // floor vheight, all neighbors forced
+ { STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial, STBVOX_FT_force, STBVOX_FT_solid }, // floor vheight, all neighbors forced
+ { STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial, STBVOX_FT_solid, STBVOX_FT_force }, // ceil vheight, all neighbors forced
+ { STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial, STBVOX_FT_solid, STBVOX_FT_force }, // ceil vheight, all neighbors forced
+};
+
+// This table indicates what normal to use for the "up" face of a sloped geom
+// @TODO this could be done with math given the current arrangement of the enum, but let's not require it
+static unsigned char stbvox_floor_slope_for_rot[4] =
+{
+ STBVF_su,
+ STBVF_wu, // @TODO: why is this reversed from what it should be? this is a north-is-up face, so slope should be south&up
+ STBVF_nu,
+ STBVF_eu,
+};
+
+static unsigned char stbvox_ceil_slope_for_rot[4] =
+{
+ STBVF_sd,
+ STBVF_ed,
+ STBVF_nd,
+ STBVF_wd,
+};
+
+// this table indicates whether, for each pair of types above, a face is visible.
+// each value indicates whether a given type is visible for all neighbor types
+static unsigned short stbvox_face_visible[STBVOX_FT_count] =
+{
+ // we encode the table by listing which cases cause *obscuration*, and bitwise inverting that
+ // table is pre-shifted by 5 to save a shift when it's accessed
+ (unsigned short) ((~0x07ff )<<5), // none is completely obscured by everything
+ (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_upper) ))<<5), // upper
+ (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_lower) ))<<5), // lower
+ (unsigned short) ((~((1<<STBVOX_FT_solid) ))<<5), // solid is only completely obscured only by solid
+ (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_diag_013)))<<5), // diag012 matches diag013
+ (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_diag_123)))<<5), // diag023 matches diag123
+ (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_diag_012)))<<5), // diag013 matches diag012
+ (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_diag_023)))<<5), // diag123 matches diag023
+ (unsigned short) ((~0 )<<5), // force is always rendered regardless, always forces neighbor
+ (unsigned short) ((~((1<<STBVOX_FT_solid) ))<<5), // partial is only completely obscured only by solid
+};
+
+// the vertex heights of the block types, in binary vertex order (zyx):
+// lower: SW, SE, NW, NE; upper: SW, SE, NW, NE
+static stbvox_mesh_vertex stbvox_geometry_vheight[8][8] =
+{
+ #define STBVOX_HEIGHTS(a,b,c,d,e,f,g,h) \
+ { stbvox_vertex_encode(0,0,a,0,0), \
+ stbvox_vertex_encode(0,0,b,0,0), \
+ stbvox_vertex_encode(0,0,c,0,0), \
+ stbvox_vertex_encode(0,0,d,0,0), \
+ stbvox_vertex_encode(0,0,e,0,0), \
+ stbvox_vertex_encode(0,0,f,0,0), \
+ stbvox_vertex_encode(0,0,g,0,0), \
+ stbvox_vertex_encode(0,0,h,0,0) }
+
+ STBVOX_HEIGHTS(0,0,0,0, 2,2,2,2),
+ STBVOX_HEIGHTS(0,0,0,0, 2,2,2,2),
+ STBVOX_HEIGHTS(0,0,0,0, 2,2,2,2),
+ STBVOX_HEIGHTS(0,0,0,0, 2,2,2,2),
+ STBVOX_HEIGHTS(1,1,1,1, 2,2,2,2),
+ STBVOX_HEIGHTS(0,0,0,0, 1,1,1,1),
+ STBVOX_HEIGHTS(0,0,0,0, 0,0,2,2),
+ STBVOX_HEIGHTS(2,2,0,0, 2,2,2,2),
+};
+
+// rotate vertices defined as [z][y][x] coords
+static unsigned char stbvox_rotate_vertex[8][4] =
+{
+ { 0,1,3,2 }, // zyx=000
+ { 1,3,2,0 }, // zyx=001
+ { 2,0,1,3 }, // zyx=010
+ { 3,2,0,1 }, // zyx=011
+ { 4,5,7,6 }, // zyx=100
+ { 5,7,6,4 }, // zyx=101
+ { 6,4,5,7 }, // zyx=110
+ { 7,6,4,5 }, // zyx=111
+};
+
+#ifdef STBVOX_CONFIG_OPTIMIZED_VHEIGHT
+// optimized vheight generates a single normal over the entire face, even if it's not planar
+static unsigned char stbvox_optimized_face_up_normal[4][4][4][4] =
+{
+ {
+ {
+ { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_ne_u, },
+ { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_nu , },
+ { STBVF_nw_u, STBVF_nw_u, STBVF_nu , STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, },
+ { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_ne_u, },
+ { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_nu , },
+ },{
+ { STBVF_eu , STBVF_eu , STBVF_eu , STBVF_eu , },
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, },
+ { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_ne_u, },
+ },{
+ { STBVF_eu , STBVF_eu , STBVF_eu , STBVF_eu , },
+ { STBVF_eu , STBVF_eu , STBVF_eu , STBVF_eu , },
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, },
+ { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, },
+ },
+ },{
+ {
+ { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , },
+ { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , },
+ { STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , },
+ { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_eu , },
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_eu , },
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_eu , },
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, },
+ },
+ },{
+ {
+ { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, },
+ { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , },
+ { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , },
+ { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, },
+ },{
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, },
+ { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , },
+ { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, },
+ { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, },
+ },
+ },{
+ {
+ { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , },
+ { STBVF_sw_u, STBVF_wu , STBVF_wu , STBVF_nw_u, },
+ { STBVF_wu , STBVF_wu , STBVF_wu , STBVF_nw_u, },
+ { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nw_u, },
+ },{
+ { STBVF_sw_u, STBVF_su , STBVF_su , STBVF_su , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , },
+ { STBVF_sw_u, STBVF_wu , STBVF_wu , STBVF_nw_u, },
+ { STBVF_wu , STBVF_wu , STBVF_wu , STBVF_nw_u, },
+ },{
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , },
+ { STBVF_sw_u, STBVF_su , STBVF_su , STBVF_su , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , },
+ { STBVF_sw_u, STBVF_wu , STBVF_wu , STBVF_nw_u, },
+ },{
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , },
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , },
+ { STBVF_sw_u, STBVF_su , STBVF_su , STBVF_su , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , },
+ },
+ },
+};
+#else
+// which normal to use for a given vheight that's planar
+// @TODO: this table was constructed by hand and may have bugs
+// nw se sw
+static unsigned char stbvox_planar_face_up_normal[4][4][4] =
+{
+ { // sw,se,nw,ne; ne = se+nw-sw
+ { STBVF_u , 0 , 0 , 0 }, // 0,0,0,0; 1,0,0,-1; 2,0,0,-2; 3,0,0,-3;
+ { STBVF_u , STBVF_u , 0 , 0 }, // 0,1,0,1; 1,1,0, 0; 2,1,0,-1; 3,1,0,-2;
+ { STBVF_wu , STBVF_nw_u, STBVF_nu , 0 }, // 0,2,0,2; 1,2,0, 1; 2,2,0, 0; 3,2,0,-1;
+ { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nu }, // 0,3,0,3; 1,3,0, 2; 2,3,0, 1; 3,3,0, 0;
+ },{
+ { STBVF_u , STBVF_u , 0 , 0 }, // 0,0,1,1; 1,0,1, 0; 2,0,1,-1; 3,0,1,-2;
+ { STBVF_sw_u, STBVF_u , STBVF_ne_u, 0 }, // 0,1,1,2; 1,1,1, 1; 2,1,1, 0; 3,1,1,-1;
+ { STBVF_sw_u, STBVF_u , STBVF_u , STBVF_ne_u }, // 0,2,1,3; 1,2,1, 2; 2,2,1, 1; 3,2,1, 0;
+ { 0 , STBVF_wu , STBVF_nw_u, STBVF_nu }, // 0,3,1,4; 1,3,1, 3; 2,3,1, 2; 3,3,1, 1;
+ },{
+ { STBVF_su , STBVF_se_u, STBVF_eu , 0 }, // 0,0,2,2; 1,0,2, 1; 2,0,2, 0; 3,0,2,-1;
+ { STBVF_sw_u, STBVF_u , STBVF_u , STBVF_ne_u }, // 0,1,2,3; 1,1,2, 2; 2,1,2, 1; 3,1,2, 0;
+ { 0 , STBVF_sw_u, STBVF_u , STBVF_ne_u }, // 0,2,2,4; 1,2,2, 3; 2,2,2, 2; 3,2,2, 1;
+ { 0 , 0 , STBVF_u , STBVF_u }, // 0,3,2,5; 1,3,2, 4; 2,3,2, 3; 3,3,2, 2;
+ },{
+ { STBVF_su , STBVF_se_u, STBVF_se_u, STBVF_eu }, // 0,0,3,3; 1,0,3, 2; 2,0,3, 1; 3,0,3, 0;
+ { 0 , STBVF_su , STBVF_se_u, STBVF_eu }, // 0,1,3,4; 1,1,3, 3; 2,1,3, 2; 3,1,3, 1;
+ { 0 , 0 , STBVF_u , STBVF_u }, // 0,2,3,5; 1,2,3, 4; 2,2,3, 3; 3,2,3, 2;
+ { 0 , 0 , 0 , STBVF_u }, // 0,3,3,6; 1,3,3, 5; 2,3,3, 4; 3,3,3, 3;
+ }
+};
+
+// these tables were constructed automatically using a variant of the code
+// below; however, they seem wrong, so who knows
+static unsigned char stbvox_face_up_normal_012[4][4][4] =
+{
+ {
+ { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_wu , STBVF_nu , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_ne_u, },
+ { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_eu , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_sw_u, STBVF_wu , STBVF_nu , STBVF_ne_u, },
+ { STBVF_sw_u, STBVF_wu , STBVF_nw_u, STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, },
+ { STBVF_sw_u, STBVF_su , STBVF_eu , STBVF_ne_u, },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_wu , STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_sw_u, STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_su , STBVF_eu , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , },
+ }
+};
+
+static unsigned char stbvox_face_up_normal_013[4][4][4] =
+{
+ {
+ { STBVF_u , STBVF_eu , STBVF_eu , STBVF_eu , },
+ { STBVF_nw_u, STBVF_nu , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_nw_u, STBVF_nw_u, STBVF_nu , STBVF_ne_u, },
+ { STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_eu , },
+ { STBVF_wu , STBVF_u , STBVF_eu , STBVF_eu , },
+ { STBVF_nw_u, STBVF_nw_u, STBVF_nu , STBVF_ne_u, },
+ { STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , },
+ { STBVF_sw_u, STBVF_su , STBVF_eu , STBVF_eu , },
+ { STBVF_wu , STBVF_wu , STBVF_u , STBVF_eu , },
+ { STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, STBVF_nu , },
+ },{
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , },
+ { STBVF_sw_u, STBVF_su , STBVF_su , STBVF_su , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_su , STBVF_eu , },
+ { STBVF_wu , STBVF_wu , STBVF_wu , STBVF_u , },
+ }
+};
+
+static unsigned char stbvox_face_up_normal_023[4][4][4] =
+{
+ {
+ { STBVF_u , STBVF_nu , STBVF_nu , STBVF_nu , },
+ { STBVF_eu , STBVF_eu , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, },
+ { STBVF_eu , STBVF_eu , STBVF_eu , STBVF_eu , },
+ },{
+ { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, },
+ { STBVF_su , STBVF_u , STBVF_nu , STBVF_nu , },
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, },
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ },{
+ { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, },
+ { STBVF_sw_u, STBVF_wu , STBVF_nw_u, STBVF_nw_u, },
+ { STBVF_su , STBVF_su , STBVF_u , STBVF_nu , },
+ { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , },
+ },{
+ { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, },
+ { STBVF_sw_u, STBVF_wu , STBVF_nw_u, STBVF_nw_u, },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_wu , STBVF_nw_u, },
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_u , },
+ }
+};
+
+static unsigned char stbvox_face_up_normal_123[4][4][4] =
+{
+ {
+ { STBVF_u , STBVF_nu , STBVF_nu , STBVF_nu , },
+ { STBVF_eu , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_eu , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_eu , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, },
+ },{
+ { STBVF_sw_u, STBVF_wu , STBVF_nw_u, STBVF_nw_u, },
+ { STBVF_su , STBVF_u , STBVF_nu , STBVF_nu , },
+ { STBVF_eu , STBVF_eu , STBVF_ne_u, STBVF_ne_u, },
+ { STBVF_eu , STBVF_eu , STBVF_ne_u, STBVF_ne_u, },
+ },{
+ { STBVF_sw_u, STBVF_sw_u, STBVF_wu , STBVF_nw_u, },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_wu , STBVF_nw_u, },
+ { STBVF_su , STBVF_su , STBVF_u , STBVF_nu , },
+ { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, },
+ },{
+ { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_wu , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_wu , },
+ { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_wu , },
+ { STBVF_su , STBVF_su , STBVF_su , STBVF_u , },
+ }
+};
+#endif
+
+void stbvox_get_quad_vertex_pointer(stbvox_mesh_maker *mm, int mesh, stbvox_mesh_vertex **vertices, stbvox_mesh_face face)
+{
+ char *p = mm->output_cur[mesh][0];
+ int step = mm->output_step[mesh][0];
+
+ // allocate a new quad from the mesh
+ vertices[0] = (stbvox_mesh_vertex *) p; p += step;
+ vertices[1] = (stbvox_mesh_vertex *) p; p += step;
+ vertices[2] = (stbvox_mesh_vertex *) p; p += step;
+ vertices[3] = (stbvox_mesh_vertex *) p; p += step;
+ mm->output_cur[mesh][0] = p;
+
+ // output the face
+ #ifdef STBVOX_ICONFIG_FACE_ATTRIBUTE
+ // write face as interleaved vertex data
+ *(stbvox_mesh_face *) (vertices[0]+1) = face;
+ *(stbvox_mesh_face *) (vertices[1]+1) = face;
+ *(stbvox_mesh_face *) (vertices[2]+1) = face;
+ *(stbvox_mesh_face *) (vertices[3]+1) = face;
+ #else
+ *(stbvox_mesh_face *) mm->output_cur[mesh][1] = face;
+ mm->output_cur[mesh][1] += 4;
+ #endif
+}
+
+void stbvox_make_mesh_for_face(stbvox_mesh_maker *mm, stbvox_rotate rot, int face, int v_off, stbvox_pos pos, stbvox_mesh_vertex vertbase, stbvox_mesh_vertex *face_coord, unsigned char mesh, int normal)
+{
+ stbvox_mesh_face face_data = stbvox_compute_mesh_face_value(mm,rot,face,v_off, normal);
+
+ // still need to compute ao & texlerp for each vertex
+
+ // first compute texlerp into p1
+ stbvox_mesh_vertex p1[4] = { 0 };
+
+ #if defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED) && defined(STBVOX_CONFIG_UP_TEXLERP_PACKED)
+ #define STBVOX_USE_PACKED(f) ((f) == STBVOX_FACE_up || (f) == STBVOX_FACE_down)
+ #elif defined(STBVOX_CONFIG_UP_TEXLERP_PACKED)
+ #define STBVOX_USE_PACKED(f) ((f) == STBVOX_FACE_up )
+ #elif defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED)
+ #define STBVOX_USE_PACKED(f) ( (f) == STBVOX_FACE_down)
+ #endif
+
+ #if defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED) || defined(STBVOX_CONFIG_UP_TEXLERP_PACKED)
+ if (STBVOX_USE_PACKED(face)) {
+ if (!mm->input.packed_compact || 0==(mm->input.packed_compact[v_off]&16))
+ goto set_default;
+ p1[0] = (mm->input.packed_compact[v_off + mm->cube_vertex_offset[face][0]] >> 5);
+ p1[1] = (mm->input.packed_compact[v_off + mm->cube_vertex_offset[face][1]] >> 5);
+ p1[2] = (mm->input.packed_compact[v_off + mm->cube_vertex_offset[face][2]] >> 5);
+ p1[3] = (mm->input.packed_compact[v_off + mm->cube_vertex_offset[face][3]] >> 5);
+ p1[0] = stbvox_vertex_encode(0,0,0,0,p1[0]);
+ p1[1] = stbvox_vertex_encode(0,0,0,0,p1[1]);
+ p1[2] = stbvox_vertex_encode(0,0,0,0,p1[2]);
+ p1[3] = stbvox_vertex_encode(0,0,0,0,p1[3]);
+ goto skip;
+ }
+ #endif
+
+ if (mm->input.block_texlerp) {
+ stbvox_block_type bt = mm->input.blocktype[v_off];
+ unsigned char val = mm->input.block_texlerp[bt];
+ p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,val);
+ } else if (mm->input.block_texlerp_face) {
+ stbvox_block_type bt = mm->input.blocktype[v_off];
+ unsigned char bt_face = STBVOX_ROTATE(face, rot.block);
+ unsigned char val = mm->input.block_texlerp_face[bt][bt_face];
+ p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,val);
+ } else if (mm->input.texlerp_face3) {
+ unsigned char val = (mm->input.texlerp_face3[v_off] >> stbvox_face3_lerp[face]) & 7;
+ if (face >= STBVOX_FACE_up)
+ val = stbvox_face3_updown[val];
+ p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,val);
+ } else if (mm->input.texlerp_simple) {
+ unsigned char val = mm->input.texlerp_simple[v_off];
+ unsigned char lerp_face = (val >> 2) & 7;
+ if (lerp_face == face) {
+ p1[0] = (mm->input.texlerp_simple[v_off + mm->cube_vertex_offset[face][0]] >> 5) & 7;
+ p1[1] = (mm->input.texlerp_simple[v_off + mm->cube_vertex_offset[face][1]] >> 5) & 7;
+ p1[2] = (mm->input.texlerp_simple[v_off + mm->cube_vertex_offset[face][2]] >> 5) & 7;
+ p1[3] = (mm->input.texlerp_simple[v_off + mm->cube_vertex_offset[face][3]] >> 5) & 7;
+ p1[0] = stbvox_vertex_encode(0,0,0,0,p1[0]);
+ p1[1] = stbvox_vertex_encode(0,0,0,0,p1[1]);
+ p1[2] = stbvox_vertex_encode(0,0,0,0,p1[2]);
+ p1[3] = stbvox_vertex_encode(0,0,0,0,p1[3]);
+ } else {
+ unsigned char base = stbvox_vert_lerp_for_simple[val&3];
+ p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,base);
+ }
+ } else if (mm->input.texlerp) {
+ unsigned char facelerp = (mm->input.texlerp[v_off] >> stbvox_face_lerp[face]) & 3;
+ if (facelerp == STBVOX_TEXLERP_FACE_use_vert) {
+ if (mm->input.texlerp_vert3 && face != STBVOX_FACE_down) {
+ unsigned char shift = stbvox_vert3_lerp[face];
+ p1[0] = (mm->input.texlerp_vert3[mm->cube_vertex_offset[face][0]] >> shift) & 7;
+ p1[1] = (mm->input.texlerp_vert3[mm->cube_vertex_offset[face][1]] >> shift) & 7;
+ p1[2] = (mm->input.texlerp_vert3[mm->cube_vertex_offset[face][2]] >> shift) & 7;
+ p1[3] = (mm->input.texlerp_vert3[mm->cube_vertex_offset[face][3]] >> shift) & 7;
+ } else {
+ p1[0] = stbvox_vert_lerp_for_simple[mm->input.texlerp[mm->cube_vertex_offset[face][0]]>>6];
+ p1[1] = stbvox_vert_lerp_for_simple[mm->input.texlerp[mm->cube_vertex_offset[face][1]]>>6];
+ p1[2] = stbvox_vert_lerp_for_simple[mm->input.texlerp[mm->cube_vertex_offset[face][2]]>>6];
+ p1[3] = stbvox_vert_lerp_for_simple[mm->input.texlerp[mm->cube_vertex_offset[face][3]]>>6];
+ }
+ p1[0] = stbvox_vertex_encode(0,0,0,0,p1[0]);
+ p1[1] = stbvox_vertex_encode(0,0,0,0,p1[1]);
+ p1[2] = stbvox_vertex_encode(0,0,0,0,p1[2]);
+ p1[3] = stbvox_vertex_encode(0,0,0,0,p1[3]);
+ } else {
+ p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,stbvox_vert_lerp_for_face_lerp[facelerp]);
+ }
+ } else {
+ #if defined(STBVOX_CONFIG_UP_TEXLERP_PACKED) || defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED)
+ set_default:
+ #endif
+ p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,7); // @TODO make this configurable
+ }
+
+ #if defined(STBVOX_CONFIG_UP_TEXLERP_PACKED) || defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED)
+ skip:
+ #endif
+
+ // now compute lighting and store to vertices
+ {
+ stbvox_mesh_vertex *mv[4];
+ stbvox_get_quad_vertex_pointer(mm, mesh, mv, face_data);
+
+ if (mm->input.lighting) {
+ // @TODO: lighting at block centers, but not gathered, instead constant-per-face
+ if (mm->input.lighting_at_vertices) {
+ int i;
+ for (i=0; i < 4; ++i) {
+ *mv[i] = vertbase + face_coord[i]
+ + stbvox_vertex_encode(0,0,0,mm->input.lighting[v_off + mm->cube_vertex_offset[face][i]] & 63,0)
+ + p1[i];
+ }
+ } else {
+ unsigned char *amb = &mm->input.lighting[v_off];
+ int i,j;
+ #if defined(STBVOX_CONFIG_ROTATION_IN_LIGHTING) || defined(STBVOX_CONFIG_VHEIGHT_IN_LIGHTING)
+ #define STBVOX_GET_LIGHTING(light) ((light) & ~3)
+ #define STBVOX_LIGHTING_ROUNDOFF 8
+ #else
+ #define STBVOX_GET_LIGHTING(light) (light)
+ #define STBVOX_LIGHTING_ROUNDOFF 2
+ #endif
+
+ for (i=0; i < 4; ++i) {
+ // for each vertex, gather from the four neighbor blocks it's facing
+ unsigned char *vamb = &amb[mm->cube_vertex_offset[face][i]];
+ int total=0;
+ for (j=0; j < 4; ++j)
+ total += STBVOX_GET_LIGHTING(vamb[mm->vertex_gather_offset[face][j]]);
+ *mv[i] = vertbase + face_coord[i]
+ + stbvox_vertex_encode(0,0,0,(total+STBVOX_LIGHTING_ROUNDOFF)>>4,0)
+ + p1[i];
+ // >> 4 is because:
+ // >> 2 to divide by 4 to get average over 4 samples
+ // >> 2 because input is 8 bits, output is 6 bits
+ }
+
+ // @TODO: note that gathering baked *lighting*
+ // is different from gathering baked ao; baked ao can count
+ // solid blocks as 0 ao, but baked lighting wants average
+ // of non-blocked--not take average & treat blocked as 0. And
+ // we can't bake the right value into the solid blocks
+ // because they can have different lighting values on
+ // different sides. So we need to actually gather and
+ // then divide by 0..4 (which we can do with a table-driven
+ // multiply, or have an 'if' for the 3 case)
+
+ }
+ } else {
+ vertbase += stbvox_vertex_encode(0,0,0,63,0);
+ *mv[0] = vertbase + face_coord[0] + p1[0];
+ *mv[1] = vertbase + face_coord[1] + p1[1];
+ *mv[2] = vertbase + face_coord[2] + p1[2];
+ *mv[3] = vertbase + face_coord[3] + p1[3];
+ }
+ }
+}
+
+// get opposite-facing normal & texgen for opposite face, used to map up-facing vheight data to down-facing data
+static unsigned char stbvox_reverse_face[STBVF_count] =
+{
+ STBVF_w, STBVF_s, STBVF_e, STBVF_n, STBVF_d , STBVF_u , STBVF_wd, STBVF_wu,
+ 0, 0, 0, 0, STBVF_sw_d, STBVF_sw_u, STBVF_sd, STBVF_su,
+ 0, 0, 0, 0, STBVF_se_d, STBVF_se_u, STBVF_ed, STBVF_eu,
+ 0, 0, 0, 0, STBVF_ne_d, STBVF_ne_d, STBVF_nd, STBVF_nu
+};
+
+#ifndef STBVOX_CONFIG_OPTIMIZED_VHEIGHT
+// render non-planar quads by splitting into two triangles, rendering each as a degenerate quad
+static void stbvox_make_12_split_mesh_for_face(stbvox_mesh_maker *mm, stbvox_rotate rot, int face, int v_off, stbvox_pos pos, stbvox_mesh_vertex vertbase, stbvox_mesh_vertex *face_coord, unsigned char mesh, unsigned char *ht)
+{
+ stbvox_mesh_vertex v[4];
+
+ unsigned char normal1 = stbvox_face_up_normal_012[ht[2]][ht[1]][ht[0]];
+ unsigned char normal2 = stbvox_face_up_normal_123[ht[3]][ht[2]][ht[1]];
+
+ if (face == STBVOX_FACE_down) {
+ normal1 = stbvox_reverse_face[normal1];
+ normal2 = stbvox_reverse_face[normal2];
+ }
+
+ // the floor side face_coord is stored in order NW,NE,SE,SW, but ht[] is stored SW,SE,NW,NE
+ v[0] = face_coord[2];
+ v[1] = face_coord[3];
+ v[2] = face_coord[0];
+ v[3] = face_coord[2];
+ stbvox_make_mesh_for_face(mm, rot, face, v_off, pos, vertbase, v, mesh, normal1);
+ v[1] = face_coord[0];
+ v[2] = face_coord[1];
+ stbvox_make_mesh_for_face(mm, rot, face, v_off, pos, vertbase, v, mesh, normal2);
+}
+
+static void stbvox_make_03_split_mesh_for_face(stbvox_mesh_maker *mm, stbvox_rotate rot, int face, int v_off, stbvox_pos pos, stbvox_mesh_vertex vertbase, stbvox_mesh_vertex *face_coord, unsigned char mesh, unsigned char *ht)
+{
+ stbvox_mesh_vertex v[4];
+
+ unsigned char normal1 = stbvox_face_up_normal_013[ht[3]][ht[1]][ht[0]];
+ unsigned char normal2 = stbvox_face_up_normal_023[ht[3]][ht[2]][ht[0]];
+
+ if (face == STBVOX_FACE_down) {
+ normal1 = stbvox_reverse_face[normal1];
+ normal2 = stbvox_reverse_face[normal2];
+ }
+
+ v[0] = face_coord[1];
+ v[1] = face_coord[2];
+ v[2] = face_coord[3];
+ v[3] = face_coord[1];
+ stbvox_make_mesh_for_face(mm, rot, face, v_off, pos, vertbase, v, mesh, normal1);
+ v[1] = face_coord[3];
+ v[2] = face_coord[0];
+ stbvox_make_mesh_for_face(mm, rot, face, v_off, pos, vertbase, v, mesh, normal2); // this one is correct!
+}
+#endif
+
+#ifndef STBVOX_CONFIG_PRECISION_Z
+#define STBVOX_CONFIG_PRECISION_Z 1
+#endif
+
+// simple case for mesh generation: we have only solid and empty blocks
+static void stbvox_make_mesh_for_block(stbvox_mesh_maker *mm, stbvox_pos pos, int v_off, stbvox_mesh_vertex *vmesh)
+{
+ int ns_off = mm->y_stride_in_bytes;
+ int ew_off = mm->x_stride_in_bytes;
+
+ unsigned char *blockptr = &mm->input.blocktype[v_off];
+ stbvox_mesh_vertex basevert = stbvox_vertex_encode(pos.x, pos.y, pos.z << STBVOX_CONFIG_PRECISION_Z , 0,0);
+
+ stbvox_rotate rot = { 0,0,0,0 };
+ unsigned char simple_rot = 0;
+
+ unsigned char mesh = mm->default_mesh;
+
+ if (mm->input.selector)
+ mesh = mm->input.selector[v_off];
+
+ // check if we're going off the end
+ if (mm->output_cur[mesh][0] + mm->output_size[mesh][0]*6 > mm->output_end[mesh][0]) {
+ mm->full = 1;
+ return;
+ }
+
+ #ifdef STBVOX_CONFIG_ROTATION_IN_LIGHTING
+ simple_rot = mm->input.lighting[v_off] & 3;
+ #endif
+
+ if (mm->input.packed_compact)
+ simple_rot = mm->input.packed_compact[v_off] & 3;
+
+ if (blockptr[ 1]==0) {
+ rot.facerot = simple_rot;
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_up , v_off, pos, basevert, vmesh+4*STBVOX_FACE_up, mesh, STBVOX_FACE_up);
+ }
+ if (blockptr[-1]==0) {
+ rot.facerot = (-simple_rot) & 3;
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_down, v_off, pos, basevert, vmesh+4*STBVOX_FACE_down, mesh, STBVOX_FACE_down);
+ }
+
+ if (mm->input.rotate) {
+ unsigned char val = mm->input.rotate[v_off];
+ rot.block = (val >> 0) & 3;
+ rot.overlay = (val >> 2) & 3;
+ //rot.tex2 = (val >> 4) & 3;
+ rot.ecolor = (val >> 6) & 3;
+ } else {
+ rot.block = rot.overlay = rot.ecolor = simple_rot;
+ }
+ rot.facerot = 0;
+
+ if (blockptr[ ns_off]==0)
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_north, v_off, pos, basevert, vmesh+4*STBVOX_FACE_north, mesh, STBVOX_FACE_north);
+ if (blockptr[-ns_off]==0)
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_south, v_off, pos, basevert, vmesh+4*STBVOX_FACE_south, mesh, STBVOX_FACE_south);
+ if (blockptr[ ew_off]==0)
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_east , v_off, pos, basevert, vmesh+4*STBVOX_FACE_east, mesh, STBVOX_FACE_east);
+ if (blockptr[-ew_off]==0)
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_west , v_off, pos, basevert, vmesh+4*STBVOX_FACE_west, mesh, STBVOX_FACE_west);
+}
+
+// complex case for mesh generation: we have lots of different
+// block types, and we don't want to generate faces of blocks
+// if they're hidden by neighbors.
+//
+// we use lots of tables to determine this: we have a table
+// which tells us what face type is generated for each type of
+// geometry, and then a table that tells us whether that type
+// is hidden by a neighbor.
+static void stbvox_make_mesh_for_block_with_geo(stbvox_mesh_maker *mm, stbvox_pos pos, int v_off)
+{
+ int ns_off = mm->y_stride_in_bytes;
+ int ew_off = mm->x_stride_in_bytes;
+ int visible_faces, visible_base;
+ unsigned char mesh;
+
+ // first gather the geometry info for this block and all neighbors
+
+ unsigned char bt, nbt[6];
+ unsigned char geo, ngeo[6];
+ unsigned char rot, nrot[6];
+
+ bt = mm->input.blocktype[v_off];
+ nbt[0] = mm->input.blocktype[v_off + ew_off];
+ nbt[1] = mm->input.blocktype[v_off + ns_off];
+ nbt[2] = mm->input.blocktype[v_off - ew_off];
+ nbt[3] = mm->input.blocktype[v_off - ns_off];
+ nbt[4] = mm->input.blocktype[v_off + 1];
+ nbt[5] = mm->input.blocktype[v_off - 1];
+ if (mm->input.geometry) {
+ int i;
+ geo = mm->input.geometry[v_off];
+ ngeo[0] = mm->input.geometry[v_off + ew_off];
+ ngeo[1] = mm->input.geometry[v_off + ns_off];
+ ngeo[2] = mm->input.geometry[v_off - ew_off];
+ ngeo[3] = mm->input.geometry[v_off - ns_off];
+ ngeo[4] = mm->input.geometry[v_off + 1];
+ ngeo[5] = mm->input.geometry[v_off - 1];
+
+ rot = (geo >> 4) & 3;
+ geo &= 15;
+ for (i=0; i < 6; ++i) {
+ nrot[i] = (ngeo[i] >> 4) & 3;
+ ngeo[i] &= 15;
+ }
+ } else {
+ int i;
+ assert(mm->input.block_geometry);
+ geo = mm->input.block_geometry[bt];
+ for (i=0; i < 6; ++i)
+ ngeo[i] = mm->input.block_geometry[nbt[i]];
+ if (mm->input.selector) {
+ #ifndef STBVOX_CONFIG_ROTATION_IN_LIGHTING
+ if (mm->input.packed_compact == NULL) {
+ rot = (mm->input.selector[v_off ] >> 4) & 3;
+ nrot[0] = (mm->input.selector[v_off + ew_off] >> 4) & 3;
+ nrot[1] = (mm->input.selector[v_off + ns_off] >> 4) & 3;
+ nrot[2] = (mm->input.selector[v_off - ew_off] >> 4) & 3;
+ nrot[3] = (mm->input.selector[v_off - ns_off] >> 4) & 3;
+ nrot[4] = (mm->input.selector[v_off + 1] >> 4) & 3;
+ nrot[5] = (mm->input.selector[v_off - 1] >> 4) & 3;
+ }
+ #endif
+ } else {
+ #ifndef STBVOX_CONFIG_ROTATION_IN_LIGHTING
+ if (mm->input.packed_compact == NULL) {
+ rot = (geo>>4)&3;
+ geo &= 15;
+ for (i=0; i < 6; ++i) {
+ nrot[i] = (ngeo[i]>>4)&3;
+ ngeo[i] &= 15;
+ }
+ }
+ #endif
+ }
+ }
+
+ #ifndef STBVOX_CONFIG_ROTATION_IN_LIGHTING
+ if (mm->input.packed_compact) {
+ rot = mm->input.packed_compact[rot] & 3;
+ nrot[0] = mm->input.packed_compact[v_off + ew_off] & 3;
+ nrot[1] = mm->input.packed_compact[v_off + ns_off] & 3;
+ nrot[2] = mm->input.packed_compact[v_off - ew_off] & 3;
+ nrot[3] = mm->input.packed_compact[v_off - ns_off] & 3;
+ nrot[4] = mm->input.packed_compact[v_off + 1] & 3;
+ nrot[5] = mm->input.packed_compact[v_off - 1] & 3;
+ }
+ #else
+ rot = mm->input.lighting[v_off] & 3;
+ nrot[0] = (mm->input.lighting[v_off + ew_off]) & 3;
+ nrot[1] = (mm->input.lighting[v_off + ns_off]) & 3;
+ nrot[2] = (mm->input.lighting[v_off - ew_off]) & 3;
+ nrot[3] = (mm->input.lighting[v_off - ns_off]) & 3;
+ nrot[4] = (mm->input.lighting[v_off + 1]) & 3;
+ nrot[5] = (mm->input.lighting[v_off - 1]) & 3;
+ #endif
+
+ if (geo == STBVOX_GEOM_transp) {
+ // transparency has a special rule: if the blocktype is the same,
+ // and the faces are compatible, then can hide them; otherwise,
+ // force them on
+ // Note that this means we don't support any transparentshapes other
+ // than solid blocks, since detecting them is too complicated. If
+ // you wanted to do something like minecraft water, you probably
+ // should just do that with a separate renderer anyway. (We don't
+ // support transparency sorting so you need to use alpha test
+ // anyway)
+ int i;
+ for (i=0; i < 6; ++i)
+ if (nbt[i] != bt) {
+ nbt[i] = 0;
+ ngeo[i] = STBVOX_GEOM_empty;
+ } else
+ ngeo[i] = STBVOX_GEOM_solid;
+ geo = STBVOX_GEOM_solid;
+ }
+
+ // now compute the face visibility
+ visible_base = stbvox_hasface[geo][rot];
+ // @TODO: assert(visible_base != 0); // we should have early-outted earlier in this case
+ visible_faces = 0;
+
+ // now, for every face that might be visible, check if neighbor hides it
+ if (visible_base & (1 << STBVOX_FACE_east)) {
+ int type = stbvox_facetype[ geo ][(STBVOX_FACE_east+ rot )&3];
+ int ntype = stbvox_facetype[ngeo[0]][(STBVOX_FACE_west+nrot[0])&3];
+ visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_east)) & (1 << STBVOX_FACE_east);
+ }
+ if (visible_base & (1 << STBVOX_FACE_north)) {
+ int type = stbvox_facetype[ geo ][(STBVOX_FACE_north+ rot )&3];
+ int ntype = stbvox_facetype[ngeo[1]][(STBVOX_FACE_south+nrot[1])&3];
+ visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_north)) & (1 << STBVOX_FACE_north);
+ }
+ if (visible_base & (1 << STBVOX_FACE_west)) {
+ int type = stbvox_facetype[ geo ][(STBVOX_FACE_west+ rot )&3];
+ int ntype = stbvox_facetype[ngeo[2]][(STBVOX_FACE_east+nrot[2])&3];
+ visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_west)) & (1 << STBVOX_FACE_west);
+ }
+ if (visible_base & (1 << STBVOX_FACE_south)) {
+ int type = stbvox_facetype[ geo ][(STBVOX_FACE_south+ rot )&3];
+ int ntype = stbvox_facetype[ngeo[3]][(STBVOX_FACE_north+nrot[3])&3];
+ visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_south)) & (1 << STBVOX_FACE_south);
+ }
+ if (visible_base & (1 << STBVOX_FACE_up)) {
+ int type = stbvox_facetype[ geo ][STBVOX_FACE_up];
+ int ntype = stbvox_facetype[ngeo[4]][STBVOX_FACE_down];
+ visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_up)) & (1 << STBVOX_FACE_up);
+ }
+ if (visible_base & (1 << STBVOX_FACE_down)) {
+ int type = stbvox_facetype[ geo ][STBVOX_FACE_down];
+ int ntype = stbvox_facetype[ngeo[5]][STBVOX_FACE_up];
+ visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_down)) & (1 << STBVOX_FACE_down);
+ }
+
+ if (geo == STBVOX_GEOM_force)
+ geo = STBVOX_GEOM_solid;
+
+ assert((geo == STBVOX_GEOM_crossed_pair) ? (visible_faces == 15) : 1);
+
+ // now we finally know for sure which faces are getting generated
+ if (visible_faces == 0)
+ return;
+
+ mesh = mm->default_mesh;
+ if (mm->input.selector)
+ mesh = mm->input.selector[v_off];
+
+ if (geo <= STBVOX_GEOM_ceil_slope_north_is_bottom) {
+ // this is the simple case, we can just use regular block gen with special vmesh calculated with vheight
+ stbvox_mesh_vertex basevert;
+ stbvox_mesh_vertex vmesh[6][4];
+ stbvox_rotate rotate = { 0,0,0,0 };
+ unsigned char simple_rot = rot;
+ int i;
+ // we only need to do this for the displayed faces, but it's easier
+ // to just do it up front; @OPTIMIZE check if it's faster to do it
+ // for visible faces only
+ for (i=0; i < 6*4; ++i) {
+ int vert = stbvox_vertex_selector[0][i];
+ vert = stbvox_rotate_vertex[vert][rot];
+ vmesh[0][i] = stbvox_vmesh_pre_vheight[0][i]
+ + stbvox_geometry_vheight[geo][vert];
+ }
+
+ basevert = stbvox_vertex_encode(pos.x, pos.y, pos.z << STBVOX_CONFIG_PRECISION_Z, 0,0);
+ if (mm->input.selector) {
+ mesh = mm->input.selector[v_off];
+ }
+
+ // check if we're going off the end
+ if (mm->output_cur[mesh][0] + mm->output_size[mesh][0]*6 > mm->output_end[mesh][0]) {
+ mm->full = 1;
+ return;
+ }
+
+ if (geo >= STBVOX_GEOM_floor_slope_north_is_top) {
+ if (visible_faces & (1 << STBVOX_FACE_up)) {
+ int normal = geo == STBVOX_GEOM_floor_slope_north_is_top ? stbvox_floor_slope_for_rot[simple_rot] : STBVOX_FACE_up;
+ rotate.facerot = simple_rot;
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, normal);
+ }
+ if (visible_faces & (1 << STBVOX_FACE_down)) {
+ int normal = geo == STBVOX_GEOM_ceil_slope_north_is_bottom ? stbvox_ceil_slope_for_rot[simple_rot] : STBVOX_FACE_down;
+ rotate.facerot = (-rotate.facerot) & 3;
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, normal);
+ }
+ } else {
+ if (visible_faces & (1 << STBVOX_FACE_up)) {
+ rotate.facerot = simple_rot;
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, STBVOX_FACE_up);
+ }
+ if (visible_faces & (1 << STBVOX_FACE_down)) {
+ rotate.facerot = (-rotate.facerot) & 3;
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, STBVOX_FACE_down);
+ }
+ }
+
+ if (mm->input.rotate) {
+ unsigned char val = mm->input.rotate[v_off];
+ rotate.block = (val >> 0) & 3;
+ rotate.overlay = (val >> 2) & 3;
+ //rotate.tex2 = (val >> 4) & 3;
+ rotate.ecolor = (val >> 6) & 3;
+ } else {
+ rotate.block = rotate.overlay = rotate.ecolor = simple_rot;
+ }
+
+ rotate.facerot = 0;
+
+ if (visible_faces & (1 << STBVOX_FACE_north))
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_north, v_off, pos, basevert, vmesh[STBVOX_FACE_north], mesh, STBVOX_FACE_north);
+ if (visible_faces & (1 << STBVOX_FACE_south))
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_south, v_off, pos, basevert, vmesh[STBVOX_FACE_south], mesh, STBVOX_FACE_south);
+ if (visible_faces & (1 << STBVOX_FACE_east))
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_east , v_off, pos, basevert, vmesh[STBVOX_FACE_east ], mesh, STBVOX_FACE_east);
+ if (visible_faces & (1 << STBVOX_FACE_west))
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_west , v_off, pos, basevert, vmesh[STBVOX_FACE_west ], mesh, STBVOX_FACE_west);
+ }
+ if (geo >= STBVOX_GEOM_floor_vheight_03) {
+ // this case can also be generated with regular block gen with special vmesh,
+ // except:
+ // if we want to generate middle diagonal for 'weird' blocks
+ // it's more complicated to detect neighbor matchups
+ stbvox_mesh_vertex vmesh[6][4];
+ stbvox_mesh_vertex cube[8];
+ stbvox_mesh_vertex basevert;
+ stbvox_rotate rotate = { 0,0,0,0 };
+ unsigned char simple_rot = rot;
+ unsigned char ht[4];
+ int extreme;
+
+ // extract the heights
+ #ifdef STBVOX_CONFIG_VHEIGHT_IN_LIGHTING
+ ht[0] = mm->input.lighting[v_off ] & 3;
+ ht[1] = mm->input.lighting[v_off+ew_off ] & 3;
+ ht[2] = mm->input.lighting[v_off +ns_off] & 3;
+ ht[3] = mm->input.lighting[v_off+ew_off+ns_off] & 3;
+ #else
+ if (mm->input.vheight) {
+ unsigned char v = mm->input.vheight[v_off];
+ ht[0] = (v >> 0) & 3;
+ ht[1] = (v >> 2) & 3;
+ ht[2] = (v >> 4) & 3;
+ ht[3] = (v >> 6) & 3;
+ } else if (mm->input.block_vheight) {
+ unsigned char v = mm->input.block_vheight[bt];
+ unsigned char raw[4];
+ int i;
+
+ raw[0] = (v >> 0) & 3;
+ raw[1] = (v >> 2) & 3;
+ raw[2] = (v >> 4) & 3;
+ raw[3] = (v >> 6) & 3;
+
+ for (i=0; i < 4; ++i)
+ ht[i] = raw[stbvox_rotate_vertex[i][rot]];
+ } else if (mm->input.packed_compact) {
+ ht[0] = (mm->input.packed_compact[v_off ] >> 2) & 3;
+ ht[1] = (mm->input.packed_compact[v_off+ew_off ] >> 2) & 3;
+ ht[2] = (mm->input.packed_compact[v_off +ns_off] >> 2) & 3;
+ ht[3] = (mm->input.packed_compact[v_off+ew_off+ns_off] >> 2) & 3;
+ } else if (mm->input.geometry) {
+ ht[0] = mm->input.geometry[v_off ] >> 6;
+ ht[1] = mm->input.geometry[v_off+ew_off ] >> 6;
+ ht[2] = mm->input.geometry[v_off +ns_off] >> 6;
+ ht[3] = mm->input.geometry[v_off+ew_off+ns_off] >> 6;
+ } else {
+ assert(0);
+ }
+ #endif
+
+ // flag whether any sides go off the top of the block, which means
+ // our visible_faces test was wrong
+ extreme = (ht[0] == 3 || ht[1] == 3 || ht[2] == 3 || ht[3] == 3);
+
+ if (geo >= STBVOX_GEOM_ceil_vheight_03) {
+ cube[0] = stbvox_vertex_encode(0,0,ht[0],0,0);
+ cube[1] = stbvox_vertex_encode(0,0,ht[1],0,0);
+ cube[2] = stbvox_vertex_encode(0,0,ht[2],0,0);
+ cube[3] = stbvox_vertex_encode(0,0,ht[3],0,0);
+ cube[4] = stbvox_vertex_encode(0,0,2,0,0);
+ cube[5] = stbvox_vertex_encode(0,0,2,0,0);
+ cube[6] = stbvox_vertex_encode(0,0,2,0,0);
+ cube[7] = stbvox_vertex_encode(0,0,2,0,0);
+ } else {
+ cube[0] = stbvox_vertex_encode(0,0,0,0,0);
+ cube[1] = stbvox_vertex_encode(0,0,0,0,0);
+ cube[2] = stbvox_vertex_encode(0,0,0,0,0);
+ cube[3] = stbvox_vertex_encode(0,0,0,0,0);
+ cube[4] = stbvox_vertex_encode(0,0,ht[0],0,0);
+ cube[5] = stbvox_vertex_encode(0,0,ht[1],0,0);
+ cube[6] = stbvox_vertex_encode(0,0,ht[2],0,0);
+ cube[7] = stbvox_vertex_encode(0,0,ht[3],0,0);
+ }
+ if (!mm->input.vheight && mm->input.block_vheight) {
+ // @TODO: support block vheight here, I've forgotten what needs to be done specially
+ }
+
+ // build vertex mesh
+ {
+ int i;
+ for (i=0; i < 6*4; ++i) {
+ int vert = stbvox_vertex_selector[0][i];
+ vmesh[0][i] = stbvox_vmesh_pre_vheight[0][i]
+ + cube[vert];
+ }
+ }
+
+ basevert = stbvox_vertex_encode(pos.x, pos.y, pos.z << STBVOX_CONFIG_PRECISION_Z, 0,0);
+ // check if we're going off the end
+ if (mm->output_cur[mesh][0] + mm->output_size[mesh][0]*6 > mm->output_end[mesh][0]) {
+ mm->full = 1;
+ return;
+ }
+
+ // @TODO generate split faces
+ if (visible_faces & (1 << STBVOX_FACE_up)) {
+ if (geo >= STBVOX_GEOM_ceil_vheight_03)
+ // flat
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, STBVOX_FACE_up);
+ else {
+ #ifndef STBVOX_CONFIG_OPTIMIZED_VHEIGHT
+ // check if it's non-planar
+ if (cube[5] + cube[6] != cube[4] + cube[7]) {
+ // not planar, split along diagonal and make degenerate quads
+ if (geo == STBVOX_GEOM_floor_vheight_03)
+ stbvox_make_03_split_mesh_for_face(mm, rotate, STBVOX_FACE_up, v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, ht);
+ else
+ stbvox_make_12_split_mesh_for_face(mm, rotate, STBVOX_FACE_up, v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, ht);
+ } else
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, stbvox_planar_face_up_normal[ht[2]][ht[1]][ht[0]]);
+ #else
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, stbvox_optimized_face_up_normal[ht[3]][ht[2]][ht[1]][ht[0]]);
+ #endif
+ }
+ }
+ if (visible_faces & (1 << STBVOX_FACE_down)) {
+ if (geo < STBVOX_GEOM_ceil_vheight_03)
+ // flat
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, STBVOX_FACE_down);
+ else {
+ #ifndef STBVOX_CONFIG_OPTIMIZED_VHEIGHT
+ // check if it's non-planar
+ if (cube[1] + cube[2] != cube[0] + cube[3]) {
+ // not planar, split along diagonal and make degenerate quads
+ if (geo == STBVOX_GEOM_ceil_vheight_03)
+ stbvox_make_03_split_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, ht);
+ else
+ stbvox_make_12_split_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, ht);
+ } else
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, stbvox_reverse_face[stbvox_planar_face_up_normal[ht[2]][ht[1]][ht[0]]]);
+ #else
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, stbvox_reverse_face[stbvox_optimized_face_up_normal[ht[3]][ht[2]][ht[1]][ht[0]]]);
+ #endif
+ }
+ }
+
+ if (mm->input.rotate) {
+ unsigned char val = mm->input.rotate[v_off];
+ rotate.block = (val >> 0) & 3;
+ rotate.overlay = (val >> 2) & 3;
+ //rotate.tex2 = (val >> 4) & 3;
+ rotate.ecolor = (val >> 6) & 3;
+ } else if (mm->input.selector) {
+ rotate.block = rotate.overlay = rotate.ecolor = simple_rot;
+ }
+
+ if ((visible_faces & (1 << STBVOX_FACE_north)) || (extreme && (ht[2] == 3 || ht[3] == 3)))
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_north, v_off, pos, basevert, vmesh[STBVOX_FACE_north], mesh, STBVOX_FACE_north);
+ if ((visible_faces & (1 << STBVOX_FACE_south)) || (extreme && (ht[0] == 3 || ht[1] == 3)))
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_south, v_off, pos, basevert, vmesh[STBVOX_FACE_south], mesh, STBVOX_FACE_south);
+ if ((visible_faces & (1 << STBVOX_FACE_east)) || (extreme && (ht[1] == 3 || ht[3] == 3)))
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_east , v_off, pos, basevert, vmesh[STBVOX_FACE_east ], mesh, STBVOX_FACE_east);
+ if ((visible_faces & (1 << STBVOX_FACE_west)) || (extreme && (ht[0] == 3 || ht[2] == 3)))
+ stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_west , v_off, pos, basevert, vmesh[STBVOX_FACE_west ], mesh, STBVOX_FACE_west);
+ }
+
+ if (geo == STBVOX_GEOM_crossed_pair) {
+ // this can be generated with a special vmesh
+ stbvox_mesh_vertex basevert = stbvox_vertex_encode(pos.x, pos.y, pos.z << STBVOX_CONFIG_PRECISION_Z , 0,0);
+ unsigned char simple_rot=0;
+ stbvox_rotate rot = { 0,0,0,0 };
+ unsigned char mesh = mm->default_mesh;
+ if (mm->input.selector) {
+ mesh = mm->input.selector[v_off];
+ simple_rot = mesh >> 4;
+ mesh &= 15;
+ }
+
+ // check if we're going off the end
+ if (mm->output_cur[mesh][0] + mm->output_size[mesh][0]*4 > mm->output_end[mesh][0]) {
+ mm->full = 1;
+ return;
+ }
+
+ if (mm->input.rotate) {
+ unsigned char val = mm->input.rotate[v_off];
+ rot.block = (val >> 0) & 3;
+ rot.overlay = (val >> 2) & 3;
+ //rot.tex2 = (val >> 4) & 3;
+ rot.ecolor = (val >> 6) & 3;
+ } else if (mm->input.selector) {
+ rot.block = rot.overlay = rot.ecolor = simple_rot;
+ }
+ rot.facerot = 0;
+
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_north, v_off, pos, basevert, stbvox_vmesh_crossed_pair[STBVOX_FACE_north], mesh, STBVF_ne_u_cross);
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_south, v_off, pos, basevert, stbvox_vmesh_crossed_pair[STBVOX_FACE_south], mesh, STBVF_sw_u_cross);
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_east , v_off, pos, basevert, stbvox_vmesh_crossed_pair[STBVOX_FACE_east ], mesh, STBVF_se_u_cross);
+ stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_west , v_off, pos, basevert, stbvox_vmesh_crossed_pair[STBVOX_FACE_west ], mesh, STBVF_nw_u_cross);
+ }
+
+
+ // @TODO
+ // STBVOX_GEOM_floor_slope_north_is_top_as_wall,
+ // STBVOX_GEOM_ceil_slope_north_is_bottom_as_wall,
+}
+
+static void stbvox_make_mesh_for_column(stbvox_mesh_maker *mm, int x, int y, int z0)
+{
+ stbvox_pos pos;
+ int v_off = x * mm->x_stride_in_bytes + y * mm->y_stride_in_bytes;
+ int ns_off = mm->y_stride_in_bytes;
+ int ew_off = mm->x_stride_in_bytes;
+ pos.x = x;
+ pos.y = y;
+ pos.z = 0;
+ if (mm->input.geometry) {
+ unsigned char *bt = mm->input.blocktype + v_off;
+ unsigned char *geo = mm->input.geometry + v_off;
+ int z;
+ for (z=z0; z < mm->z1; ++z) {
+ if (bt[z] && ( !bt[z+ns_off] || !STBVOX_GET_GEO(geo[z+ns_off]) || !bt[z-ns_off] || !STBVOX_GET_GEO(geo[z-ns_off])
+ || !bt[z+ew_off] || !STBVOX_GET_GEO(geo[z+ew_off]) || !bt[z-ew_off] || !STBVOX_GET_GEO(geo[z-ew_off])
+ || !bt[z-1] || !STBVOX_GET_GEO(geo[z-1]) || !bt[z+1] || !STBVOX_GET_GEO(geo[z+1])))
+ { // TODO check up and down
+ pos.z = z;
+ stbvox_make_mesh_for_block_with_geo(mm, pos, v_off+z);
+ if (mm->full) {
+ mm->cur_z = z;
+ return;
+ }
+ }
+ }
+ } else if (mm->input.block_geometry) {
+ int z;
+ unsigned char *bt = mm->input.blocktype + v_off;
+ unsigned char *geo = mm->input.block_geometry;
+ for (z=z0; z < mm->z1; ++z) {
+ if (bt[z] && ( geo[bt[z+ns_off]] != STBVOX_GEOM_solid
+ || geo[bt[z-ns_off]] != STBVOX_GEOM_solid
+ || geo[bt[z+ew_off]] != STBVOX_GEOM_solid
+ || geo[bt[z-ew_off]] != STBVOX_GEOM_solid
+ || geo[bt[z-1]] != STBVOX_GEOM_solid
+ || geo[bt[z+1]] != STBVOX_GEOM_solid))
+ {
+ pos.z = z;
+ stbvox_make_mesh_for_block_with_geo(mm, pos, v_off+z);
+ if (mm->full) {
+ mm->cur_z = z;
+ return;
+ }
+ }
+ }
+ } else {
+ unsigned char *bt = mm->input.blocktype + v_off;
+ int z;
+ #if STBVOX_CONFIG_PRECISION_Z == 1
+ stbvox_mesh_vertex *vmesh = stbvox_vmesh_delta_half_z[0];
+ #else
+ stbvox_mesh_vertex *vmesh = stbvox_vmesh_delta_normal[0];
+ #endif
+ for (z=z0; z < mm->z1; ++z) {
+ // if it's solid and at least one neighbor isn't solid
+ if (bt[z] && (!bt[z+ns_off] || !bt[z-ns_off] || !bt[z+ew_off] || !bt[z-ew_off] || !bt[z-1] || !bt[z+1])) {
+ pos.z = z;
+ stbvox_make_mesh_for_block(mm, pos, v_off+z, vmesh);
+ if (mm->full) {
+ mm->cur_z = z;
+ return;
+ }
+ }
+ }
+ }
+}
+
+static void stbvox_bring_up_to_date(stbvox_mesh_maker *mm)
+{
+ if (mm->config_dirty) {
+ int i;
+ #ifdef STBVOX_ICONFIG_FACE_ATTRIBUTE
+ mm->num_mesh_slots = 1;
+ for (i=0; i < STBVOX_MAX_MESHES; ++i) {
+ mm->output_size[i][0] = 32;
+ mm->output_step[i][0] = 8;
+ }
+ #else
+ mm->num_mesh_slots = 2;
+ for (i=0; i < STBVOX_MAX_MESHES; ++i) {
+ mm->output_size[i][0] = 16;
+ mm->output_step[i][0] = 4;
+ mm->output_size[i][1] = 4;
+ mm->output_step[i][1] = 4;
+ }
+ #endif
+
+ mm->config_dirty = 0;
+ }
+}
+
+int stbvox_make_mesh(stbvox_mesh_maker *mm)
+{
+ int x,y;
+ stbvox_bring_up_to_date(mm);
+ mm->full = 0;
+ if (mm->cur_x > mm->x0 || mm->cur_y > mm->y0 || mm->cur_z > mm->z0) {
+ stbvox_make_mesh_for_column(mm, mm->cur_x, mm->cur_y, mm->cur_z);
+ if (mm->full)
+ return 0;
+ ++mm->cur_y;
+ while (mm->cur_y < mm->y1 && !mm->full) {
+ stbvox_make_mesh_for_column(mm, mm->cur_x, mm->cur_y, mm->z0);
+ if (mm->full)
+ return 0;
+ ++mm->cur_y;
+ }
+ ++mm->cur_x;
+ }
+ for (x=mm->cur_x; x < mm->x1; ++x) {
+ for (y=mm->y0; y < mm->y1; ++y) {
+ stbvox_make_mesh_for_column(mm, x, y, mm->z0);
+ if (mm->full) {
+ mm->cur_x = x;
+ mm->cur_y = y;
+ return 0;
+ }
+ }
+ }
+ return 1;
+}
+
+void stbvox_init_mesh_maker(stbvox_mesh_maker *mm)
+{
+ memset(mm, 0, sizeof(*mm));
+ stbvox_build_default_palette();
+
+ mm->config_dirty = 1;
+ mm->default_mesh = 0;
+}
+
+int stbvox_get_buffer_count(stbvox_mesh_maker *mm)
+{
+ stbvox_bring_up_to_date(mm);
+ return mm->num_mesh_slots;
+}
+
+int stbvox_get_buffer_size_per_quad(stbvox_mesh_maker *mm, int n)
+{
+ return mm->output_size[0][n];
+}
+
+void stbvox_reset_buffers(stbvox_mesh_maker *mm)
+{
+ int i;
+ for (i=0; i < STBVOX_MAX_MESHES*STBVOX_MAX_MESH_SLOTS; ++i) {
+ mm->output_cur[0][i] = 0;
+ mm->output_buffer[0][i] = 0;
+ }
+}
+
+void stbvox_set_buffer(stbvox_mesh_maker *mm, int mesh, int slot, void *buffer, size_t len)
+{
+ int i;
+ stbvox_bring_up_to_date(mm);
+ mm->output_buffer[mesh][slot] = (char *) buffer;
+ mm->output_cur [mesh][slot] = (char *) buffer;
+ mm->output_len [mesh][slot] = len;
+ mm->output_end [mesh][slot] = (char *) buffer + len;
+ for (i=0; i < STBVOX_MAX_MESH_SLOTS; ++i) {
+ if (mm->output_buffer[mesh][i]) {
+ assert(mm->output_len[mesh][i] / mm->output_size[mesh][i] == mm->output_len[mesh][slot] / mm->output_size[mesh][slot]);
+ }
+ }
+}
+
+void stbvox_set_default_mesh(stbvox_mesh_maker *mm, int mesh)
+{
+ mm->default_mesh = mesh;
+}
+
+int stbvox_get_quad_count(stbvox_mesh_maker *mm, int mesh)
+{
+ return (mm->output_cur[mesh][0] - mm->output_buffer[mesh][0]) / mm->output_size[mesh][0];
+}
+
+stbvox_input_description *stbvox_get_input_description(stbvox_mesh_maker *mm)
+{
+ return &mm->input;
+}
+
+void stbvox_set_input_range(stbvox_mesh_maker *mm, int x0, int y0, int z0, int x1, int y1, int z1)
+{
+ mm->x0 = x0;
+ mm->y0 = y0;
+ mm->z0 = z0;
+
+ mm->x1 = x1;
+ mm->y1 = y1;
+ mm->z1 = z1;
+
+ mm->cur_x = x0;
+ mm->cur_y = y0;
+ mm->cur_z = z0;
+
+ // @TODO validate that this range is representable in this mode
+}
+
+void stbvox_get_transform(stbvox_mesh_maker *mm, float transform[3][3])
+{
+ // scale
+ transform[0][0] = 1.0;
+ transform[0][1] = 1.0;
+ #if STBVOX_CONFIG_PRECISION_Z==1
+ transform[0][2] = 0.5f;
+ #else
+ transform[0][2] = 1.0f;
+ #endif
+ // translation
+ transform[1][0] = (float) (mm->pos_x);
+ transform[1][1] = (float) (mm->pos_y);
+ transform[1][2] = (float) (mm->pos_z);
+ // texture coordinate projection translation
+ transform[2][0] = (float) (mm->pos_x & 255); // @TODO depends on max texture scale
+ transform[2][1] = (float) (mm->pos_y & 255);
+ transform[2][2] = (float) (mm->pos_z & 255);
+}
+
+void stbvox_get_bounds(stbvox_mesh_maker *mm, float bounds[2][3])
+{
+ bounds[0][0] = (float) (mm->pos_x + mm->x0);
+ bounds[0][1] = (float) (mm->pos_y + mm->y0);
+ bounds[0][2] = (float) (mm->pos_z + mm->z0);
+ bounds[1][0] = (float) (mm->pos_x + mm->x1);
+ bounds[1][1] = (float) (mm->pos_y + mm->y1);
+ bounds[1][2] = (float) (mm->pos_z + mm->z1);
+}
+
+void stbvox_set_mesh_coordinates(stbvox_mesh_maker *mm, int x, int y, int z)
+{
+ mm->pos_x = x;
+ mm->pos_y = y;
+ mm->pos_z = z;
+}
+
+void stbvox_set_input_stride(stbvox_mesh_maker *mm, int x_stride_in_bytes, int y_stride_in_bytes)
+{
+ int f,v;
+ mm->x_stride_in_bytes = x_stride_in_bytes;
+ mm->y_stride_in_bytes = y_stride_in_bytes;
+ for (f=0; f < 6; ++f) {
+ for (v=0; v < 4; ++v) {
+ mm->cube_vertex_offset[f][v] = stbvox_vertex_vector[f][v][0] * mm->x_stride_in_bytes
+ + stbvox_vertex_vector[f][v][1] * mm->y_stride_in_bytes
+ + stbvox_vertex_vector[f][v][2] ;
+ mm->vertex_gather_offset[f][v] = (stbvox_vertex_vector[f][v][0]-1) * mm->x_stride_in_bytes
+ + (stbvox_vertex_vector[f][v][1]-1) * mm->y_stride_in_bytes
+ + (stbvox_vertex_vector[f][v][2]-1) ;
+ }
+ }
+}
+
+/////////////////////////////////////////////////////////////////////////////
+//
+// offline computation of tables
+//
+
+#if 0
+// compute optimized vheight table
+static char *normal_names[32] =
+{
+ 0,0,0,0,"u ",0, "eu ",0,
+ 0,0,0,0,"ne_u",0, "nu ",0,
+ 0,0,0,0,"nw_u",0, "wu ",0,
+ 0,0,0,0,"sw_u",0, "su ",0,
+};
+
+static char *find_best_normal(float x, float y, float z)
+{
+ int best_slot = 4;
+ float best_dot = 0;
+ int i;
+ for (i=0; i < 32; ++i) {
+ if (normal_names[i]) {
+ float dot = x * stbvox_default_normals[i][0] + y * stbvox_default_normals[i][1] + z * stbvox_default_normals[i][2];
+ if (dot > best_dot) {
+ best_dot = dot;
+ best_slot = i;
+ }
+ }
+ }
+ return normal_names[best_slot];
+}
+
+int main(int argc, char **argv)
+{
+ int sw,se,nw,ne;
+ for (ne=0; ne < 4; ++ne) {
+ for (nw=0; nw < 4; ++nw) {
+ for (se=0; se < 4; ++se) {
+ printf(" { ");
+ for (sw=0; sw < 4; ++sw) {
+ float x = (float) (nw + sw - ne - se);
+ float y = (float) (sw + se - nw - ne);
+ float z = 2;
+ printf("STBVF_%s, ", find_best_normal(x,y,z));
+ }
+ printf("},\n");
+ }
+ }
+ }
+ return 0;
+}
+#endif
+
+// @TODO
+//
+// - test API for texture rotation on side faces
+// - API for texture rotation on top & bottom
+// - better culling of vheight faces with vheight neighbors
+// - better culling of non-vheight faces with vheight neighbors
+// - gather vertex lighting from slopes correctly
+// - better support texture edge_clamp: currently if you fall
+// exactly on 1.0 you get wrapped incorrectly; this is rare, but
+// can avoid: compute texcoords in vertex shader, offset towards
+// center before modding, need 2 bits per vertex to know offset direction)
+// - other mesh modes (10,6,4-byte quads)
+//
+//
+// With TexBuffer for the fixed vertex data, we can actually do
+// minecrafty non-blocks like stairs -- we still probably only
+// want 256 or so, so we can't do the equivalent of all the vheight
+// combos, but that's ok. The 256 includes baked rotations, but only
+// some of them need it, and lots of block types share some faces.
+//
+// mode 5 (6 bytes): mode 6 (6 bytes)
+// x:7 x:6
+// y:7 y:6
+// z:6 z:6
+// tex1:8 tex1:8
+// tex2:8 tex2:7
+// color:8 color:8
+// face:4 face:7
+//
+//
+// side faces (all x4) top&bottom faces (2x) internal faces (1x)
+// 1 regular 1 regular
+// 2 slabs 2
+// 8 stairs 4 stairs 16
+// 4 diag side 8
+// 4 upper diag side 8
+// 4 lower diag side 8
+// 4 crossed pairs
+//
+// 23*4 + 5*4 + 46
+// == 92 + 20 + 46 = 158
+//
+// Must drop 30 of them to fit in 7 bits:
+// ceiling half diagonals: 16+8 = 24
+// Need to get rid of 6 more.
+// ceiling diagonals: 8+4 = 12
+// This brings it to 122, so can add a crossed-pair variant.
+// (diagonal and non-diagonal, or randomly offset)
+// Or carpet, which would be 5 more.
+//
+//
+// Mode 4 (10 bytes):
+// v: z:2,light:6
+// f: x:6,y:6,z:7, t1:8,t2:8,c:8,f:5
+//
+// Mode ? (10 bytes)
+// v: xyz:5 (27 values), light:3
+// f: x:7,y:7,z:6, t1:8,t2:8,c:8,f:4
+// (v: x:2,y:2,z:2,light:2)
+
+#endif // STB_VOXEL_RENDER_IMPLEMENTATION
projects / henge / apc.git / blobdiff