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change 3dc name to bc5

pull/290/merge
Sean Barrett 2017-03-03 08:49:08 -08:00
parent c39063727d
commit a217948c16
1 changed files with 9 additions and 8 deletions
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17
stb_dxt.h
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@ -1,4 +1,4 @@
// stb_dxt.h - v1.04 - DXT1/DXT5 compressor - public domain // stb_dxt.h - v1.05 - DXT1/DXT5 compressor - public domain
// original by fabian "ryg" giesen - ported to C by stb // original by fabian "ryg" giesen - ported to C by stb
// use '#define STB_DXT_IMPLEMENTATION' before including to create the implementation // use '#define STB_DXT_IMPLEMENTATION' before including to create the implementation
// //
@ -9,6 +9,7 @@
// and "high quality" using mode. // and "high quality" using mode.
// //
// version history: // version history:
// v1.05 - (stb) support bc5/3dc (Arvids Kokins)
// v1.04 - (ryg) default to no rounding bias for lerped colors (as per S3TC/DX10 spec); // v1.04 - (ryg) default to no rounding bias for lerped colors (as per S3TC/DX10 spec);
// single color match fix (allow for inexact color interpolation); // single color match fix (allow for inexact color interpolation);
// optimal DXT5 index finder; "high quality" mode that runs multiple refinement steps. // optimal DXT5 index finder; "high quality" mode that runs multiple refinement steps.
@ -30,7 +31,7 @@
#define STB_DXT_HIGHQUAL 2 // high quality mode, does two refinement steps instead of 1. ~30-40% slower. #define STB_DXT_HIGHQUAL 2 // high quality mode, does two refinement steps instead of 1. ~30-40% slower.
void stb_compress_dxt_block(unsigned char *dest, const unsigned char *src, int alpha, int mode); void stb_compress_dxt_block(unsigned char *dest, const unsigned char *src, int alpha, int mode);
void stb_compress_3dc_block_rgxx8(unsigned char *dest, const unsigned char *src, int mode); void stb_compress_bc5_block_rg88(unsigned char *dest, const unsigned char *src, int mode);
#define STB_COMPRESS_DXT_BLOCK #define STB_COMPRESS_DXT_BLOCK
#ifdef STB_DXT_IMPLEMENTATION #ifdef STB_DXT_IMPLEMENTATION
@ -537,7 +538,7 @@ static void stb__CompressColorBlock(unsigned char *dest, unsigned char *block, i
} }
// Alpha block compression (this is easy for a change) // Alpha block compression (this is easy for a change)
static void stb__CompressAlphaBlock(unsigned char *dest,unsigned char *src,int mode) static void stb__CompressAlphaBlock(unsigned char *dest,unsigned char *src, int stride)
{ {
int i,dist,bias,dist4,dist2,bits,mask; int i,dist,bias,dist4,dist2,bits,mask;
@ -567,7 +568,7 @@ static void stb__CompressAlphaBlock(unsigned char *dest,unsigned char *src,int m
bits = 0,mask=0; bits = 0,mask=0;
for (i=0;i<16;i++) { for (i=0;i<16;i++) {
int a = src[i*4+3]*7 + bias; int a = src[i*stride]*7 + bias;
int ind,t; int ind,t;
// select index. this is a "linear scale" lerp factor between 0 (val=min) and 7 (val=max). // select index. this is a "linear scale" lerp factor between 0 (val=min) and 7 (val=max).
@ -618,17 +619,17 @@ void stb_compress_dxt_block(unsigned char *dest, const unsigned char *src, int a
} }
if (alpha) { if (alpha) {
stb__CompressAlphaBlock(dest,(unsigned char*) src,mode); stb__CompressAlphaBlock(dest,(unsigned char*) src+3, 4);
dest += 8; dest += 8;
} }
stb__CompressColorBlock(dest,(unsigned char*) src,mode); stb__CompressColorBlock(dest,(unsigned char*) src,mode);
} }
void stb_compress_3dc_block_rgxx8(unsigned char *dest, const unsigned char *src, int mode) void stb_compress_bc5_block_rg88(unsigned char *dest, const unsigned char *src)
{ {
stb__CompressAlphaBlock(dest,(unsigned char*) src - 3,mode); stb__CompressAlphaBlock(dest,(unsigned char*) src,2);
stb__CompressAlphaBlock(dest + 8,(unsigned char*) src - 2,mode); stb__CompressAlphaBlock(dest + 8,(unsigned char*) src+1,2);
} }
#endif // STB_DXT_IMPLEMENTATION #endif // STB_DXT_IMPLEMENTATION
#endif // STB_INCLUDE_STB_DXT_H #endif // STB_INCLUDE_STB_DXT_H