-/*
- * DXTn codec
- * Version: 1.1
- *
- * Copyright (C) 2004 Daniel Borca All Rights Reserved.
- *
- * this is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * this is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with GNU Make; see the file COPYING. If not, write to
- * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-/* Copyright (C) 2007 Hiroshi Morii <koolsmoky(at)users.sourceforge.net>
- * Added support for ARGB inputs, DXT3,5 workaround for ATI Radeons, and
- * YUV conversions to determine representative colors.
- */
-
-
-#include <stdlib.h>
-#include <string.h>
-#include <assert.h>
-
-#include <stdio.h>
-
-#include "types.h"
-#include "internal.h"
-#include "dxtn.h"
-
-
-/***************************************************************************\
- * DXTn encoder
- *
- * The encoder was built by reversing the decoder,
- * and is vaguely based on FXT1 codec. Note that this code
- * is merely a proof of concept, since it is highly UNoptimized!
-\***************************************************************************/
-
-
-#define MAX_COMP 4 /* ever needed maximum number of components in texel */
-#define MAX_VECT 4 /* ever needed maximum number of base vectors to find */
-#define N_TEXELS 16 /* number of texels in a block (always 16) */
-#define COLOR565(v) (word)((((v)[RCOMP] & 0xf8) << 8) | (((v)[GCOMP] & 0xfc) << 3) | ((v)[BCOMP] >> 3))
-
-
-static const int dxtn_color_tlat[2][4] = {
- { 0, 2, 3, 1 },
- { 0, 2, 1, 3 }
-};
-
-static const int dxtn_alpha_tlat[2][8] = {
- { 0, 2, 3, 4, 5, 6, 7, 1 },
- { 0, 2, 3, 4, 5, 1, 6, 7 }
-};
-
-
-static void
-dxt1_rgb_quantize (dword *cc, const byte *lines[], int comps)
-{
- float b, iv[MAX_COMP]; /* interpolation vector */
-
- dword hi; /* high doubleword */
- int color0, color1;
- int n_vect;
- const int n_comp = 3;
- int black = 0;
-
-#ifndef YUV
- int minSum = 2000; /* big enough */
-#else
- int minSum = 2000000;
-#endif
- int maxSum = -1; /* small enough */
- int minCol = 0; /* phoudoin: silent compiler! */
- int maxCol = 0; /* phoudoin: silent compiler! */
-
- byte input[N_TEXELS][MAX_COMP];
- int i, k, l;
-
- /* make the whole block opaque */
- /* we will NEVER reference ACOMP of any pixel */
-
- /* 4 texels each line */
-#ifndef ARGB
- for (l = 0; l < 4; l++) {
- for (k = 0; k < 4; k++) {
- for (i = 0; i < comps; i++) {
- input[k + l * 4][i] = *lines[l]++;
- }
- }
- }
-#else
- /* H.Morii - support for ARGB inputs */
- for (l = 0; l < 4; l++) {
- for (k = 0; k < 4; k++) {
- input[k + l * 4][2] = *lines[l]++;
- input[k + l * 4][1] = *lines[l]++;
- input[k + l * 4][0] = *lines[l]++;
- if (comps == 4) input[k + l * 4][3] = *lines[l]++;
- }
- }
-#endif
-
- /* Our solution here is to find the darkest and brightest colors in
- * the 4x4 tile and use those as the two representative colors.
- * There are probably better algorithms to use (histogram-based).
- */
- for (k = 0; k < N_TEXELS; k++) {
- int sum = 0;
-#ifndef YUV
- for (i = 0; i < n_comp; i++) {
- sum += input[k][i];
- }
-#else
- /* RGB to YUV conversion according to CCIR 601 specs
- * Y = 0.299R+0.587G+0.114B
- * U = 0.713(R - Y) = 0.500R-0.419G-0.081B
- * V = 0.564(B - Y) = -0.169R-0.331G+0.500B
- */
- sum = 299 * input[k][RCOMP] + 587 * input[k][GCOMP] + 114 * input[k][BCOMP];
-#endif
- if (minSum > sum) {
- minSum = sum;
- minCol = k;
- }
- if (maxSum < sum) {
- maxSum = sum;
- maxCol = k;
- }
- if (sum == 0) {
- black = 1;
- }
- }
-
- color0 = COLOR565(input[minCol]);
- color1 = COLOR565(input[maxCol]);
-
- if (color0 == color1) {
- /* we'll use 3-vector */
- cc[0] = color0 | (color1 << 16);
- hi = black ? -1 : 0;
- } else {
- if (black && ((color0 == 0) || (color1 == 0))) {
- /* we still can use 4-vector */
- black = 0;
- }
-
- if (black ^ (color0 <= color1)) {
- int aux;
- aux = color0;
- color0 = color1;
- color1 = aux;
- aux = minCol;
- minCol = maxCol;
- maxCol = aux;
- }
- n_vect = (color0 <= color1) ? 2 : 3;
-
- MAKEIVEC(n_vect, n_comp, iv, b, input[minCol], input[maxCol]);
-
- /* add in texels */
- cc[0] = color0 | (color1 << 16);
- hi = 0;
- for (k = N_TEXELS - 1; k >= 0; k--) {
- int texel = 3;
- int sum = 0;
- if (black) {
- for (i = 0; i < n_comp; i++) {
- sum += input[k][i];
- }
- }
- if (!black || sum) {
- /* interpolate color */
- CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
- texel = dxtn_color_tlat[black][texel];
- }
- /* add in texel */
- hi <<= 2;
- hi |= texel;
- }
- }
- cc[1] = hi;
-}
-
-
-static void
-dxt1_rgba_quantize (dword *cc, const byte *lines[], int comps)
-{
- float b, iv[MAX_COMP]; /* interpolation vector */
-
- dword hi; /* high doubleword */
- int color0, color1;
- int n_vect;
- const int n_comp = 3;
- int transparent = 0;
-
-#ifndef YUV
- int minSum = 2000; /* big enough */
-#else
- int minSum = 2000000;
-#endif
- int maxSum = -1; /* small enough */
- int minCol = 0; /* phoudoin: silent compiler! */
- int maxCol = 0; /* phoudoin: silent compiler! */
-
- byte input[N_TEXELS][MAX_COMP];
- int i, k, l;
-
- if (comps == 3) {
- /* make the whole block opaque */
- memset(input, -1, sizeof(input));
- }
-
- /* 4 texels each line */
-#ifndef ARGB
- for (l = 0; l < 4; l++) {
- for (k = 0; k < 4; k++) {
- for (i = 0; i < comps; i++) {
- input[k + l * 4][i] = *lines[l]++;
- }
- }
- }
-#else
- /* H.Morii - support for ARGB inputs */
- for (l = 0; l < 4; l++) {
- for (k = 0; k < 4; k++) {
- input[k + l * 4][2] = *lines[l]++;
- input[k + l * 4][1] = *lines[l]++;
- input[k + l * 4][0] = *lines[l]++;
- if (comps == 4) input[k + l * 4][3] = *lines[l]++;
- }
- }
-#endif
-
- /* Our solution here is to find the darkest and brightest colors in
- * the 4x4 tile and use those as the two representative colors.
- * There are probably better algorithms to use (histogram-based).
- */
- for (k = 0; k < N_TEXELS; k++) {
- int sum = 0;
-#ifndef YUV
- for (i = 0; i < n_comp; i++) {
- sum += input[k][i];
- }
-#else
- sum = 299 * input[k][RCOMP] + 587 * input[k][GCOMP] + 114 * input[k][BCOMP];
-#endif
- if (minSum > sum) {
- minSum = sum;
- minCol = k;
- }
- if (maxSum < sum) {
- maxSum = sum;
- maxCol = k;
- }
- if (input[k][ACOMP] < 128) {
- transparent = 1;
- }
- }
-
- color0 = COLOR565(input[minCol]);
- color1 = COLOR565(input[maxCol]);
-
- if (color0 == color1) {
- /* we'll use 3-vector */
- cc[0] = color0 | (color1 << 16);
- hi = transparent ? -1 : 0;
- } else {
- if (transparent ^ (color0 <= color1)) {
- int aux;
- aux = color0;
- color0 = color1;
- color1 = aux;
- aux = minCol;
- minCol = maxCol;
- maxCol = aux;
- }
- n_vect = (color0 <= color1) ? 2 : 3;
-
- MAKEIVEC(n_vect, n_comp, iv, b, input[minCol], input[maxCol]);
-
- /* add in texels */
- cc[0] = color0 | (color1 << 16);
- hi = 0;
- for (k = N_TEXELS - 1; k >= 0; k--) {
- int texel = 3;
- if (input[k][ACOMP] >= 128) {
- /* interpolate color */
- CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
- texel = dxtn_color_tlat[transparent][texel];
- }
- /* add in texel */
- hi <<= 2;
- hi |= texel;
- }
- }
- cc[1] = hi;
-}
-
-
-static void
-dxt3_rgba_quantize (dword *cc, const byte *lines[], int comps)
-{
- float b, iv[MAX_COMP]; /* interpolation vector */
-
- dword lolo, lohi; /* low quadword: lo dword, hi dword */
- dword hihi; /* high quadword: high dword */
- int color0, color1;
- const int n_vect = 3;
- const int n_comp = 3;
-
-#ifndef YUV
- int minSum = 2000; /* big enough */
-#else
- int minSum = 2000000;
-#endif
- int maxSum = -1; /* small enough */
- int minCol = 0; /* phoudoin: silent compiler! */
- int maxCol = 0; /* phoudoin: silent compiler! */
-
- byte input[N_TEXELS][MAX_COMP];
- int i, k, l;
-
- if (comps == 3) {
- /* make the whole block opaque */
- memset(input, -1, sizeof(input));
- }
-
- /* 4 texels each line */
-#ifndef ARGB
- for (l = 0; l < 4; l++) {
- for (k = 0; k < 4; k++) {
- for (i = 0; i < comps; i++) {
- input[k + l * 4][i] = *lines[l]++;
- }
- }
- }
-#else
- /* H.Morii - support for ARGB inputs */
- for (l = 0; l < 4; l++) {
- for (k = 0; k < 4; k++) {
- input[k + l * 4][2] = *lines[l]++;
- input[k + l * 4][1] = *lines[l]++;
- input[k + l * 4][0] = *lines[l]++;
- if (comps == 4) input[k + l * 4][3] = *lines[l]++;
- }
- }
-#endif
-
- /* Our solution here is to find the darkest and brightest colors in
- * the 4x4 tile and use those as the two representative colors.
- * There are probably better algorithms to use (histogram-based).
- */
- for (k = 0; k < N_TEXELS; k++) {
- int sum = 0;
-#ifndef YUV
- for (i = 0; i < n_comp; i++) {
- sum += input[k][i];
- }
-#else
- sum = 299 * input[k][RCOMP] + 587 * input[k][GCOMP] + 114 * input[k][BCOMP];
-#endif
- if (minSum > sum) {
- minSum = sum;
- minCol = k;
- }
- if (maxSum < sum) {
- maxSum = sum;
- maxCol = k;
- }
- }
-
- /* add in alphas */
- lolo = lohi = 0;
- for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
- /* add in alpha */
- lohi <<= 4;
- lohi |= input[k][ACOMP] >> 4;
- }
- cc[1] = lohi;
- for (; k >= 0; k--) {
- /* add in alpha */
- lolo <<= 4;
- lolo |= input[k][ACOMP] >> 4;
- }
- cc[0] = lolo;
-
- color0 = COLOR565(input[minCol]);
- color1 = COLOR565(input[maxCol]);
-
-#ifdef RADEON
- /* H.Morii - Workaround for ATI Radeon
- * According to the OpenGL EXT_texture_compression_s3tc specs,
- * the encoding of the RGB components for DXT3 and DXT5 formats
- * use the non-transparent encodings of DXT1 but treated as
- * though color0 > color1, regardless of the actual values of
- * color0 and color1. ATI Radeons however require the values to
- * be color0 > color1.
- */
- if (color0 < color1) {
- int aux;
- aux = color0;
- color0 = color1;
- color1 = aux;
- aux = minCol;
- minCol = maxCol;
- maxCol = aux;
- }
-#endif
-
- cc[2] = color0 | (color1 << 16);
-
- hihi = 0;
- if (color0 != color1) {
- MAKEIVEC(n_vect, n_comp, iv, b, input[minCol], input[maxCol]);
-
- /* add in texels */
- for (k = N_TEXELS - 1; k >= 0; k--) {
- int texel;
- /* interpolate color */
- CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
- texel = dxtn_color_tlat[0][texel];
- /* add in texel */
- hihi <<= 2;
- hihi |= texel;
- }
- }
- cc[3] = hihi;
-}
-
-
-static void
-dxt5_rgba_quantize (dword *cc, const byte *lines[], int comps)
-{
- float b, iv[MAX_COMP]; /* interpolation vector */
-
- qword lo; /* low quadword */
- dword hihi; /* high quadword: high dword */
- int color0, color1;
- const int n_vect = 3;
- const int n_comp = 3;
-
-#ifndef YUV
- int minSum = 2000; /* big enough */
-#else
- int minSum = 2000000;
-#endif
- int maxSum = -1; /* small enough */
- int minCol = 0; /* phoudoin: silent compiler! */
- int maxCol = 0; /* phoudoin: silent compiler! */
- int alpha0 = 2000; /* big enough */
- int alpha1 = -1; /* small enough */
- int anyZero = 0, anyOne = 0;
- int a_vect;
-
- byte input[N_TEXELS][MAX_COMP];
- int i, k, l;
-
- if (comps == 3) {
- /* make the whole block opaque */
- memset(input, -1, sizeof(input));
- }
-
- /* 4 texels each line */
-#ifndef ARGB
- for (l = 0; l < 4; l++) {
- for (k = 0; k < 4; k++) {
- for (i = 0; i < comps; i++) {
- input[k + l * 4][i] = *lines[l]++;
- }
- }
- }
-#else
- /* H.Morii - support for ARGB inputs */
- for (l = 0; l < 4; l++) {
- for (k = 0; k < 4; k++) {
- input[k + l * 4][2] = *lines[l]++;
- input[k + l * 4][1] = *lines[l]++;
- input[k + l * 4][0] = *lines[l]++;
- if (comps == 4) input[k + l * 4][3] = *lines[l]++;
- }
- }
-#endif
-
- /* Our solution here is to find the darkest and brightest colors in
- * the 4x4 tile and use those as the two representative colors.
- * There are probably better algorithms to use (histogram-based).
- */
- for (k = 0; k < N_TEXELS; k++) {
- int sum = 0;
-#ifndef YUV
- for (i = 0; i < n_comp; i++) {
- sum += input[k][i];
- }
-#else
- sum = 299 * input[k][RCOMP] + 587 * input[k][GCOMP] + 114 * input[k][BCOMP];
-#endif
- if (minSum > sum) {
- minSum = sum;
- minCol = k;
- }
- if (maxSum < sum) {
- maxSum = sum;
- maxCol = k;
- }
- if (alpha0 > input[k][ACOMP]) {
- alpha0 = input[k][ACOMP];
- }
- if (alpha1 < input[k][ACOMP]) {
- alpha1 = input[k][ACOMP];
- }
- if (input[k][ACOMP] == 0) {
- anyZero = 1;
- }
- if (input[k][ACOMP] == 255) {
- anyOne = 1;
- }
- }
-
- /* add in alphas */
- if (alpha0 == alpha1) {
- /* we'll use 6-vector */
- cc[0] = alpha0 | (alpha1 << 8);
- cc[1] = 0;
- } else {
- if (anyZero && ((alpha0 == 0) || (alpha1 == 0))) {
- /* we still might use 8-vector */
- anyZero = 0;
- }
- if (anyOne && ((alpha0 == 255) || (alpha1 == 255))) {
- /* we still might use 8-vector */
- anyOne = 0;
- }
- if ((anyZero | anyOne) ^ (alpha0 <= alpha1)) {
- int aux;
- aux = alpha0;
- alpha0 = alpha1;
- alpha1 = aux;
- }
- a_vect = (alpha0 <= alpha1) ? 5 : 7;
-
- /* compute interpolation vector */
- iv[ACOMP] = (float)a_vect / (alpha1 - alpha0);
- b = -iv[ACOMP] * alpha0 + 0.5F;
-
- /* add in alphas */
- Q_MOV32(lo, 0);
- for (k = N_TEXELS - 1; k >= 0; k--) {
- int texel = -1;
- if (anyZero | anyOne) {
- if (input[k][ACOMP] == 0) {
- texel = 6;
- } else if (input[k][ACOMP] == 255) {
- texel = 7;
- }
- }
- /* interpolate alpha */
- if (texel == -1) {
- float dot = input[k][ACOMP] * iv[ACOMP];
- texel = (int)(dot + b);
-#if SAFECDOT
- if (texel < 0) {
- texel = 0;
- } else if (texel > a_vect) {
- texel = a_vect;
- }
-#endif
- texel = dxtn_alpha_tlat[anyZero | anyOne][texel];
- }
- /* add in texel */
- Q_SHL(lo, 3);
- Q_OR32(lo, texel);
- }
- Q_SHL(lo, 16);
- Q_OR32(lo, alpha0 | (alpha1 << 8));
- ((qword *)cc)[0] = lo;
- }
-
- color0 = COLOR565(input[minCol]);
- color1 = COLOR565(input[maxCol]);
-
-#ifdef RADEON /* H.Morii - Workaround for ATI Radeon */
- if (color0 < color1) {
- int aux;
- aux = color0;
- color0 = color1;
- color1 = aux;
- aux = minCol;
- minCol = maxCol;
- maxCol = aux;
- }
-#endif
-
- cc[2] = color0 | (color1 << 16);
-
- hihi = 0;
- if (color0 != color1) {
- MAKEIVEC(n_vect, n_comp, iv, b, input[minCol], input[maxCol]);
-
- /* add in texels */
- for (k = N_TEXELS - 1; k >= 0; k--) {
- int texel;
- /* interpolate color */
- CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
- texel = dxtn_color_tlat[0][texel];
- /* add in texel */
- hihi <<= 2;
- hihi |= texel;
- }
- }
- cc[3] = hihi;
-}
-
-
-#define ENCODER(dxtn, n) \
-int TAPIENTRY \
-dxtn##_encode (int width, int height, int comps, \
- const void *source, int srcRowStride, \
- void *dest, int destRowStride) \
-{ \
- int x, y; \
- const byte *data; \
- dword *encoded = (dword *)dest; \
- void *newSource = NULL; \
- \
- /* Replicate image if width is not M4 or height is not M4 */ \
- if ((width & 3) | (height & 3)) { \
- int newWidth = (width + 3) & ~3; \
- int newHeight = (height + 3) & ~3; \
- newSource = malloc(comps * newWidth * newHeight * sizeof(byte *));\
- _mesa_upscale_teximage2d(width, height, newWidth, newHeight, \
- comps, (const byte *)source, \
- srcRowStride, (byte *)newSource); \
- source = newSource; \
- width = newWidth; \
- height = newHeight; \
- srcRowStride = comps * newWidth; \
- } \
- \
- data = (const byte *)source; \
- destRowStride = (destRowStride - width * n) / 4; \
- for (y = 0; y < height; y += 4) { \
- unsigned int offs = 0 + (y + 0) * srcRowStride; \
- for (x = 0; x < width; x += 4) { \
- const byte *lines[4]; \
- lines[0] = &data[offs]; \
- lines[1] = lines[0] + srcRowStride; \
- lines[2] = lines[1] + srcRowStride; \
- lines[3] = lines[2] + srcRowStride; \
- offs += 4 * comps; \
- dxtn##_quantize(encoded, lines, comps); \
- /* 4x4 block */ \
- encoded += n; \
- } \
- encoded += destRowStride; \
- } \
- \
- if (newSource != NULL) { \
- free(newSource); \
- } \
- \
- return 0; \
-}
-
-ENCODER(dxt1_rgb, 2)
-ENCODER(dxt1_rgba, 2)
-ENCODER(dxt3_rgba, 4)
-ENCODER(dxt5_rgba, 4)
-
-
-/***************************************************************************\
- * DXTn decoder
- *
- * The decoder is based on GL_EXT_texture_compression_s3tc
- * specification and serves as a concept for the encoder.
-\***************************************************************************/
-
-
-/* lookup table for scaling 4 bit colors up to 8 bits */
-static const byte _rgb_scale_4[] = {
- 0, 17, 34, 51, 68, 85, 102, 119,
- 136, 153, 170, 187, 204, 221, 238, 255
-};
-
-/* lookup table for scaling 5 bit colors up to 8 bits */
-static const byte _rgb_scale_5[] = {
- 0, 8, 16, 25, 33, 41, 49, 58,
- 66, 74, 82, 90, 99, 107, 115, 123,
- 132, 140, 148, 156, 165, 173, 181, 189,
- 197, 206, 214, 222, 230, 239, 247, 255
-};
-
-/* lookup table for scaling 6 bit colors up to 8 bits */
-static const byte _rgb_scale_6[] = {
- 0, 4, 8, 12, 16, 20, 24, 28,
- 32, 36, 40, 45, 49, 53, 57, 61,
- 65, 69, 73, 77, 81, 85, 89, 93,
- 97, 101, 105, 109, 113, 117, 121, 125,
- 130, 134, 138, 142, 146, 150, 154, 158,
- 162, 166, 170, 174, 178, 182, 186, 190,
- 194, 198, 202, 206, 210, 215, 219, 223,
- 227, 231, 235, 239, 243, 247, 251, 255
-};
-
-
-#define CC_SEL(cc, which) (((dword *)(cc))[(which) / 32] >> ((which) & 31))
-#define UP4(c) _rgb_scale_4[(c) & 15]
-#define UP5(c) _rgb_scale_5[(c) & 31]
-#define UP6(c) _rgb_scale_6[(c) & 63]
-#define ZERO_4UBV(v) *((dword *)(v)) = 0
-
-
-void TAPIENTRY
-dxt1_rgb_decode_1 (const void *texture, int stride,
- int i, int j, byte *rgba)
-{
- const byte *src = (const byte *)texture
- + ((j / 4) * ((stride + 3) / 4) + i / 4) * 8;
- const int code = (src[4 + (j & 3)] >> ((i & 3) * 2)) & 0x3;
- if (code == 0) {
- rgba[RCOMP] = UP5(CC_SEL(src, 11));
- rgba[GCOMP] = UP6(CC_SEL(src, 5));
- rgba[BCOMP] = UP5(CC_SEL(src, 0));
- } else if (code == 1) {
- rgba[RCOMP] = UP5(CC_SEL(src, 27));
- rgba[GCOMP] = UP6(CC_SEL(src, 21));
- rgba[BCOMP] = UP5(CC_SEL(src, 16));
- } else {
- const word col0 = src[0] | (src[1] << 8);
- const word col1 = src[2] | (src[3] << 8);
- if (col0 > col1) {
- if (code == 2) {
- rgba[RCOMP] = (UP5(col0 >> 11) * 2 + UP5(col1 >> 11)) / 3;
- rgba[GCOMP] = (UP6(col0 >> 5) * 2 + UP6(col1 >> 5)) / 3;
- rgba[BCOMP] = (UP5(col0 ) * 2 + UP5(col1 )) / 3;
- } else {
- rgba[RCOMP] = (UP5(col0 >> 11) + 2 * UP5(col1 >> 11)) / 3;
- rgba[GCOMP] = (UP6(col0 >> 5) + 2 * UP6(col1 >> 5)) / 3;
- rgba[BCOMP] = (UP5(col0 ) + 2 * UP5(col1 )) / 3;
- }
- } else {
- if (code == 2) {
- rgba[RCOMP] = (UP5(col0 >> 11) + UP5(col1 >> 11)) / 2;
- rgba[GCOMP] = (UP6(col0 >> 5) + UP6(col1 >> 5)) / 2;
- rgba[BCOMP] = (UP5(col0 ) + UP5(col1 )) / 2;
- } else {
- ZERO_4UBV(rgba);
- }
- }
- }
- rgba[ACOMP] = 255;
-}
-
-
-void TAPIENTRY
-dxt1_rgba_decode_1 (const void *texture, int stride,
- int i, int j, byte *rgba)
-{
- /* Same as rgb_dxt1 above, except alpha=0 if col0<=col1 and code=3. */
- const byte *src = (const byte *)texture
- + ((j / 4) * ((stride + 3) / 4) + i / 4) * 8;
- const int code = (src[4 + (j & 3)] >> ((i & 3) * 2)) & 0x3;
- if (code == 0) {
- rgba[RCOMP] = UP5(CC_SEL(src, 11));
- rgba[GCOMP] = UP6(CC_SEL(src, 5));
- rgba[BCOMP] = UP5(CC_SEL(src, 0));
- rgba[ACOMP] = 255;
- } else if (code == 1) {
- rgba[RCOMP] = UP5(CC_SEL(src, 27));
- rgba[GCOMP] = UP6(CC_SEL(src, 21));
- rgba[BCOMP] = UP5(CC_SEL(src, 16));
- rgba[ACOMP] = 255;
- } else {
- const word col0 = src[0] | (src[1] << 8);
- const word col1 = src[2] | (src[3] << 8);
- if (col0 > col1) {
- if (code == 2) {
- rgba[RCOMP] = (UP5(col0 >> 11) * 2 + UP5(col1 >> 11)) / 3;
- rgba[GCOMP] = (UP6(col0 >> 5) * 2 + UP6(col1 >> 5)) / 3;
- rgba[BCOMP] = (UP5(col0 ) * 2 + UP5(col1 )) / 3;
- } else {
- rgba[RCOMP] = (UP5(col0 >> 11) + 2 * UP5(col1 >> 11)) / 3;
- rgba[GCOMP] = (UP6(col0 >> 5) + 2 * UP6(col1 >> 5)) / 3;
- rgba[BCOMP] = (UP5(col0 ) + 2 * UP5(col1 )) / 3;
- }
- rgba[ACOMP] = 255;
- } else {
- if (code == 2) {
- rgba[RCOMP] = (UP5(col0 >> 11) + UP5(col1 >> 11)) / 2;
- rgba[GCOMP] = (UP6(col0 >> 5) + UP6(col1 >> 5)) / 2;
- rgba[BCOMP] = (UP5(col0 ) + UP5(col1 )) / 2;
- rgba[ACOMP] = 255;
- } else {
- ZERO_4UBV(rgba);
- }
- }
- }
-}
-
-
-void TAPIENTRY
-dxt3_rgba_decode_1 (const void *texture, int stride,
- int i, int j, byte *rgba)
-{
- const byte *src = (const byte *)texture
- + ((j / 4) * ((stride + 3) / 4) + i / 4) * 16;
- const int code = (src[12 + (j & 3)] >> ((i & 3) * 2)) & 0x3;
- const dword *cc = (const dword *)(src + 8);
- if (code == 0) {
- rgba[RCOMP] = UP5(CC_SEL(cc, 11));
- rgba[GCOMP] = UP6(CC_SEL(cc, 5));
- rgba[BCOMP] = UP5(CC_SEL(cc, 0));
- } else if (code == 1) {
- rgba[RCOMP] = UP5(CC_SEL(cc, 27));
- rgba[GCOMP] = UP6(CC_SEL(cc, 21));
- rgba[BCOMP] = UP5(CC_SEL(cc, 16));
- } else if (code == 2) {
- /* (col0 * (4 - code) + col1 * (code - 1)) / 3 */
- rgba[RCOMP] = (UP5(CC_SEL(cc, 11)) * 2 + UP5(CC_SEL(cc, 27))) / 3;
- rgba[GCOMP] = (UP6(CC_SEL(cc, 5)) * 2 + UP6(CC_SEL(cc, 21))) / 3;
- rgba[BCOMP] = (UP5(CC_SEL(cc, 0)) * 2 + UP5(CC_SEL(cc, 16))) / 3;
- } else {
- rgba[RCOMP] = (UP5(CC_SEL(cc, 11)) + 2 * UP5(CC_SEL(cc, 27))) / 3;
- rgba[GCOMP] = (UP6(CC_SEL(cc, 5)) + 2 * UP6(CC_SEL(cc, 21))) / 3;
- rgba[BCOMP] = (UP5(CC_SEL(cc, 0)) + 2 * UP5(CC_SEL(cc, 16))) / 3;
- }
- rgba[ACOMP] = UP4(src[((j & 3) * 4 + (i & 3)) / 2] >> ((i & 1) * 4));
-}
-
-
-void TAPIENTRY
-dxt5_rgba_decode_1 (const void *texture, int stride,
- int i, int j, byte *rgba)
-{
- const byte *src = (const byte *)texture
- + ((j / 4) * ((stride + 3) / 4) + i / 4) * 16;
- const int code = (src[12 + (j & 3)] >> ((i & 3) * 2)) & 0x3;
- const dword *cc = (const dword *)(src + 8);
- const byte alpha0 = src[0];
- const byte alpha1 = src[1];
- const int alphaShift = (((j & 3) * 4) + (i & 3)) * 3 + 16;
- const int acode = ((alphaShift == 31)
- ? CC_SEL(src + 2, alphaShift - 16)
- : CC_SEL(src, alphaShift)) & 0x7;
- if (code == 0) {
- rgba[RCOMP] = UP5(CC_SEL(cc, 11));
- rgba[GCOMP] = UP6(CC_SEL(cc, 5));
- rgba[BCOMP] = UP5(CC_SEL(cc, 0));
- } else if (code == 1) {
- rgba[RCOMP] = UP5(CC_SEL(cc, 27));
- rgba[GCOMP] = UP6(CC_SEL(cc, 21));
- rgba[BCOMP] = UP5(CC_SEL(cc, 16));
- } else if (code == 2) {
- /* (col0 * (4 - code) + col1 * (code - 1)) / 3 */
- rgba[RCOMP] = (UP5(CC_SEL(cc, 11)) * 2 + UP5(CC_SEL(cc, 27))) / 3;
- rgba[GCOMP] = (UP6(CC_SEL(cc, 5)) * 2 + UP6(CC_SEL(cc, 21))) / 3;
- rgba[BCOMP] = (UP5(CC_SEL(cc, 0)) * 2 + UP5(CC_SEL(cc, 16))) / 3;
- } else {
- rgba[RCOMP] = (UP5(CC_SEL(cc, 11)) + 2 * UP5(CC_SEL(cc, 27))) / 3;
- rgba[GCOMP] = (UP6(CC_SEL(cc, 5)) + 2 * UP6(CC_SEL(cc, 21))) / 3;
- rgba[BCOMP] = (UP5(CC_SEL(cc, 0)) + 2 * UP5(CC_SEL(cc, 16))) / 3;
- }
- if (acode == 0) {
- rgba[ACOMP] = alpha0;
- } else if (acode == 1) {
- rgba[ACOMP] = alpha1;
- } else if (alpha0 > alpha1) {
- rgba[ACOMP] = ((8 - acode) * alpha0 + (acode - 1) * alpha1) / 7;
- } else if (acode == 6) {
- rgba[ACOMP] = 0;
- } else if (acode == 7) {
- rgba[ACOMP] = 255;
- } else {
- rgba[ACOMP] = ((6 - acode) * alpha0 + (acode - 1) * alpha1) / 5;
- }
-}