From 2702c90d7a39fca2a3319c5e915fd290cb31fc70 Mon Sep 17 00:00:00 2001 From: Radosław Kujawa Date: Fri, 17 Jul 2026 14:54:32 +0200 Subject: Initial import. --- src/mesa/main/texcompress_fxt1.c | 1777 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 1777 insertions(+) create mode 100644 src/mesa/main/texcompress_fxt1.c (limited to 'src/mesa/main/texcompress_fxt1.c') diff --git a/src/mesa/main/texcompress_fxt1.c b/src/mesa/main/texcompress_fxt1.c new file mode 100644 index 0000000..c33a003 --- /dev/null +++ b/src/mesa/main/texcompress_fxt1.c @@ -0,0 +1,1777 @@ +/* + * Mesa 3-D graphics library + * Version: 6.1 + * + * Copyright (C) 1999-2004 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + + +/** + * \file texcompress_fxt1.c + * GL_EXT_texture_compression_fxt1 support. + */ + + +#include "glheader.h" +#include "imports.h" +#include "colormac.h" +#include "context.h" +#include "convolve.h" +#include "image.h" +#include "texcompress.h" +#include "texformat.h" +#include "texstore.h" + + +int +fxt1_encode (GLcontext *ctx, + unsigned int width, unsigned int height, + int srcFormat, + const void *source, int srcRowStride, + void *dest, int destRowStride); +void +fxt1_decode_1 (const void *texture, int width, + int i, int j, unsigned char *rgba); + + +/** + * Called during context initialization. + */ +void +_mesa_init_texture_fxt1( GLcontext *ctx ) +{ + (void) ctx; +} + + +/** + * Called via TexFormat->StoreImage to store an RGB_FXT1 texture. + */ +static GLboolean +texstore_rgb_fxt1(STORE_PARAMS) +{ + const GLchan *pixels; + GLint srcRowStride; + GLubyte *dst; + const GLint texWidth = dstRowStride * 8 / 16; /* a bit of a hack */ + const GLchan *tempImage = NULL; + + ASSERT(dstFormat == &_mesa_texformat_rgb_fxt1); + ASSERT(dstXoffset % 8 == 0); + ASSERT(dstYoffset % 4 == 0); + ASSERT(dstZoffset == 0); + (void) dstZoffset; (void) dstImageStride; + + if (srcFormat != GL_RGB || + srcType != CHAN_TYPE || + ctx->_ImageTransferState || + srcPacking->SwapBytes) { + /* convert image to RGB/GLchan */ + tempImage = _mesa_make_temp_chan_image(ctx, dims, + baseInternalFormat, + dstFormat->BaseFormat, + srcWidth, srcHeight, srcDepth, + srcFormat, srcType, srcAddr, + srcPacking); + if (!tempImage) + return GL_FALSE; /* out of memory */ + _mesa_adjust_image_for_convolution(ctx, dims, &srcWidth, &srcHeight); + pixels = tempImage; + srcRowStride = 3 * srcWidth; + srcFormat = GL_RGB; + } + else { + pixels = (const GLchan *) srcAddr; + srcRowStride = _mesa_image_row_stride(srcPacking, srcWidth, srcFormat, + srcType) / sizeof(GLchan); + } + + dst = _mesa_compressed_image_address(dstXoffset, dstYoffset, 0, + GL_COMPRESSED_RGB_FXT1_3DFX, + texWidth, (GLubyte *) dstAddr); + + fxt1_encode(ctx, srcWidth, srcHeight, srcFormat, pixels, srcRowStride, + dst, dstRowStride); + + if (tempImage) + _mesa_free((void*) tempImage); + + return GL_TRUE; +} + + +/** + * Called via TexFormat->StoreImage to store an RGBA_FXT1 texture. + */ +static GLboolean +texstore_rgba_fxt1(STORE_PARAMS) +{ + const GLchan *pixels; + GLint srcRowStride; + GLubyte *dst; + GLint texWidth = dstRowStride * 8 / 16; /* a bit of a hack */ + const GLchan *tempImage = NULL; + + ASSERT(dstFormat == &_mesa_texformat_rgba_fxt1); + ASSERT(dstXoffset % 8 == 0); + ASSERT(dstYoffset % 4 == 0); + ASSERT(dstZoffset == 0); + (void) dstZoffset; (void) dstImageStride; + + if (srcFormat != GL_RGBA || + srcType != CHAN_TYPE || + ctx->_ImageTransferState || + srcPacking->SwapBytes) { + /* convert image to RGBA/GLchan */ + tempImage = _mesa_make_temp_chan_image(ctx, dims, + baseInternalFormat, + dstFormat->BaseFormat, + srcWidth, srcHeight, srcDepth, + srcFormat, srcType, srcAddr, + srcPacking); + if (!tempImage) + return GL_FALSE; /* out of memory */ + _mesa_adjust_image_for_convolution(ctx, dims, &srcWidth, &srcHeight); + pixels = tempImage; + srcRowStride = 4 * srcWidth; + srcFormat = GL_RGBA; + } + else { + pixels = (const GLchan *) srcAddr; + srcRowStride = _mesa_image_row_stride(srcPacking, srcWidth, srcFormat, + srcType) / sizeof(GLchan); + } + + dst = _mesa_compressed_image_address(dstXoffset, dstYoffset, 0, + GL_COMPRESSED_RGBA_FXT1_3DFX, + texWidth, (GLubyte *) dstAddr); + + fxt1_encode(ctx, srcWidth, srcHeight, srcFormat, pixels, srcRowStride, + dst, dstRowStride); + + if (tempImage) + _mesa_free((void*) tempImage); + + return GL_TRUE; +} + + +static void +fetch_texel_2d_rgba_fxt1( const struct gl_texture_image *texImage, + GLint i, GLint j, GLint k, GLchan *texel ) +{ + (void) k; + fxt1_decode_1(texImage->Data, texImage->Width, i, j, texel); +} + + +static void +fetch_texel_2d_f_rgba_fxt1( const struct gl_texture_image *texImage, + GLint i, GLint j, GLint k, GLfloat *texel ) +{ + /* just sample as GLchan and convert to float here */ + GLchan rgba[4]; + (void) k; + fxt1_decode_1(texImage->Data, texImage->Width, i, j, rgba); + texel[RCOMP] = CHAN_TO_FLOAT(rgba[RCOMP]); + texel[GCOMP] = CHAN_TO_FLOAT(rgba[GCOMP]); + texel[BCOMP] = CHAN_TO_FLOAT(rgba[BCOMP]); + texel[ACOMP] = CHAN_TO_FLOAT(rgba[ACOMP]); +} + + +static void +fetch_texel_2d_rgb_fxt1( const struct gl_texture_image *texImage, + GLint i, GLint j, GLint k, GLchan *texel ) +{ + (void) k; + fxt1_decode_1(texImage->Data, texImage->Width, i, j, texel); + texel[ACOMP] = 255; +} + + +static void +fetch_texel_2d_f_rgb_fxt1( const struct gl_texture_image *texImage, + GLint i, GLint j, GLint k, GLfloat *texel ) +{ + /* just sample as GLchan and convert to float here */ + GLchan rgba[4]; + (void) k; + fxt1_decode_1(texImage->Data, texImage->Width, i, j, rgba); + texel[RCOMP] = CHAN_TO_FLOAT(rgba[RCOMP]); + texel[GCOMP] = CHAN_TO_FLOAT(rgba[GCOMP]); + texel[BCOMP] = CHAN_TO_FLOAT(rgba[BCOMP]); + texel[ACOMP] = 1.0; +} + + + +const struct gl_texture_format _mesa_texformat_rgb_fxt1 = { + MESA_FORMAT_RGB_FXT1, /* MesaFormat */ + GL_RGB, /* BaseFormat */ + GL_UNSIGNED_NORMALIZED_ARB, /* DataType */ + 4, /*approx*/ /* RedBits */ + 4, /*approx*/ /* GreenBits */ + 4, /*approx*/ /* BlueBits */ + 0, /* AlphaBits */ + 0, /* LuminanceBits */ + 0, /* IntensityBits */ + 0, /* IndexBits */ + 0, /* DepthBits */ + 0, /* TexelBytes */ + texstore_rgb_fxt1, /* StoreTexImageFunc */ + NULL, /*impossible*/ /* FetchTexel1D */ + fetch_texel_2d_rgb_fxt1, /* FetchTexel2D */ + NULL, /*impossible*/ /* FetchTexel3D */ + NULL, /*impossible*/ /* FetchTexel1Df */ + fetch_texel_2d_f_rgb_fxt1, /* FetchTexel2Df */ + NULL, /*impossible*/ /* FetchTexel3Df */ +}; + +const struct gl_texture_format _mesa_texformat_rgba_fxt1 = { + MESA_FORMAT_RGBA_FXT1, /* MesaFormat */ + GL_RGBA, /* BaseFormat */ + GL_UNSIGNED_NORMALIZED_ARB, /* DataType */ + 4, /*approx*/ /* RedBits */ + 4, /*approx*/ /* GreenBits */ + 4, /*approx*/ /* BlueBits */ + 1, /*approx*/ /* AlphaBits */ + 0, /* LuminanceBits */ + 0, /* IntensityBits */ + 0, /* IndexBits */ + 0, /* DepthBits */ + 0, /* TexelBytes */ + texstore_rgba_fxt1, /* StoreTexImageFunc */ + NULL, /*impossible*/ /* FetchTexel1D */ + fetch_texel_2d_rgba_fxt1, /* FetchTexel2D */ + NULL, /*impossible*/ /* FetchTexel3D */ + NULL, /*impossible*/ /* FetchTexel1Df */ + fetch_texel_2d_f_rgba_fxt1, /* FetchTexel2Df */ + NULL, /*impossible*/ /* FetchTexel3Df */ +}; + + +/***************************************************************************\ + * FXT1 encoder + * + * The encoder was built by reversing the decoder, + * and is vaguely based on Texus2 by 3dfx. Note that this code + * is merely a proof of concept, since it is higly UNoptimized; + * moreover, it is sub-optimal due to inital conditions passed + * to Lloyd's algorithm (the interpolation modes are worse). +\***************************************************************************/ + + +#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 32 /* number of texels in a block (always 32) */ +#define LL_N_REP 50 /* number of iterations in lloyd's vq */ +#define LL_RMS_D 10 /* fault tolerance (maximum delta) */ +#define LL_RMS_E 255 /* fault tolerance (maximum error) */ +#define ALPHA_TS 2 /* alpha threshold: (255 - ALPHA_TS) deemed opaque */ +#define ISTBLACK(v) (*((unsigned long *)(v)) == 0) + + +#ifdef __GNUC__ + +#define FX64_NATIVE 1 + +typedef unsigned long long Fx64; + +#define FX64_MOV32(a, b) a = b +#define FX64_OR32(a, b) a |= b +#define FX64_SHL(a, c) a <<= c + +#else /* !__GNUC__ */ + +#define FX64_NATIVE 0 + +typedef struct { + unsigned long lo, hi; +} Fx64; + +#define FX64_MOV32(a, b) a.lo = b +#define FX64_OR32(a, b) a.lo |= b + +#define FX64_SHL(a, c) \ + do { \ + if ((c) >= 32) { \ + a.hi = a.lo << ((c) - 32); \ + a.lo = 0; \ + } else { \ + a.hi = (a.hi << (c)) | (a.lo >> (32 - (c))); \ + a.lo <<= (c); \ + } \ + } while (0) + +#endif /* !__GNUC__ */ + + +static int +fxt1_bestcol (float vec[][MAX_COMP], int nv, + unsigned char input[MAX_COMP], int nc) +{ + int i, j, best = -1; + float err = 1e9; /* big enough */ + + for (j = 0; j < nv; j++) { + float e = 0; + for (i = 0; i < nc; i++) { + e += (vec[j][i] - input[i]) * (vec[j][i] - input[i]); + } + if (e < err) { + err = e; + best = j; + } + } + + return best; +} + + +static int +fxt1_worst (float vec[MAX_COMP], + unsigned char input[N_TEXELS][MAX_COMP], int nc, int n) +{ + int i, k, worst = -1; + float err = -1; /* small enough */ + + for (k = 0; k < n; k++) { + float e = 0; + for (i = 0; i < nc; i++) { + e += (vec[i] - input[k][i]) * (vec[i] - input[k][i]); + } + if (e > err) { + err = e; + worst = k; + } + } + + return worst; +} + + +static int +fxt1_variance (double variance[MAX_COMP], + unsigned char input[N_TEXELS][MAX_COMP], int nc, int n) +{ + int i, k, best = 0; + int sx, sx2; + double var, maxvar = -1; /* small enough */ + double teenth = 1.0 / n; + + for (i = 0; i < nc; i++) { + sx = sx2 = 0; + for (k = 0; k < n; k++) { + int t = input[k][i]; + sx += t; + sx2 += t * t; + } + var = sx2 * teenth - sx * sx * teenth * teenth; + if (maxvar < var) { + maxvar = var; + best = i; + } + if (variance) { + variance[i] = var; + } + } + + return best; +} + + +static int +fxt1_choose (float vec[][MAX_COMP], int nv, + unsigned char input[N_TEXELS][MAX_COMP], int nc, int n) +{ +#if 0 + /* Choose colors from a grid. + */ + int i, j; + + for (j = 0; j < nv; j++) { + int m = j * (n - 1) / (nv - 1); + for (i = 0; i < nc; i++) { + vec[j][i] = input[m][i]; + } + } +#else + /* Our solution here is to find the darkest and brightest colors in + * the 8x4 tile and use those as the two representative colors. + * There are probably better algorithms to use (histogram-based). + */ + int i, j, k; + int minSum = 1000; /* big enough */ + int maxSum = -1; /* small enough */ + int minCol = 0; /* phoudoin: silent compiler! */ + int maxCol = 0; /* phoudoin: silent compiler! */ + + struct { + int flag; + int key; + int freq; + int idx; + } hist[N_TEXELS]; + int lenh = 0; + + memset(hist, 0, sizeof(hist)); + + for (k = 0; k < n; k++) { + int l; + int key = 0; + int sum = 0; + for (i = 0; i < nc; i++) { + key <<= 8; + key |= input[k][i]; + sum += input[k][i]; + } + for (l = 0; l < n; l++) { + if (!hist[l].flag) { + /* alloc new slot */ + hist[l].flag = !0; + hist[l].key = key; + hist[l].freq = 1; + hist[l].idx = k; + lenh = l + 1; + break; + } else if (hist[l].key == key) { + hist[l].freq++; + break; + } + } + if (minSum > sum) { + minSum = sum; + minCol = k; + } + if (maxSum < sum) { + maxSum = sum; + maxCol = k; + } + } + + if (lenh <= nv) { + for (j = 0; j < lenh; j++) { + for (i = 0; i < nc; i++) { + vec[j][i] = (float)input[hist[j].idx][i]; + } + } + for (; j < nv; j++) { + for (i = 0; i < nc; i++) { + vec[j][i] = vec[0][i]; + } + } + return 0; + } + + for (j = 0; j < nv; j++) { + for (i = 0; i < nc; i++) { + vec[j][i] = ((nv - 1 - j) * input[minCol][i] + j * input[maxCol][i] + (nv - 1) / 2) / (nv - 1); + } + } +#endif + + return !0; +} + + +static int +fxt1_lloyd (float vec[][MAX_COMP], int nv, + unsigned char input[N_TEXELS][MAX_COMP], int nc, int n) +{ + /* Use the generalized lloyd's algorithm for VQ: + * find 4 color vectors. + * + * for each sample color + * sort to nearest vector. + * + * replace each vector with the centroid of it's matching colors. + * + * repeat until RMS doesn't improve. + * + * if a color vector has no samples, or becomes the same as another + * vector, replace it with the color which is farthest from a sample. + * + * vec[][MAX_COMP] initial vectors and resulting colors + * nv number of resulting colors required + * input[N_TEXELS][MAX_COMP] input texels + * nc number of components in input / vec + * n number of input samples + */ + + int sum[MAX_VECT][MAX_COMP]; /* used to accumulate closest texels */ + int cnt[MAX_VECT]; /* how many times a certain vector was chosen */ + float error, lasterror = 1e9; + + int i, j, k, rep; + + /* the quantizer */ + for (rep = 0; rep < LL_N_REP; rep++) { + /* reset sums & counters */ + for (j = 0; j < nv; j++) { + for (i = 0; i < nc; i++) { + sum[j][i] = 0; + } + cnt[j] = 0; + } + error = 0; + + /* scan whole block */ + for (k = 0; k < n; k++) { +#if 1 + int best = -1; + float err = 1e9; /* big enough */ + /* determine best vector */ + for (j = 0; j < nv; j++) { + float e = (vec[j][0] - input[k][0]) * (vec[j][0] - input[k][0]) + + (vec[j][1] - input[k][1]) * (vec[j][1] - input[k][1]) + + (vec[j][2] - input[k][2]) * (vec[j][2] - input[k][2]); + if (nc == 4) { + e += (vec[j][3] - input[k][3]) * (vec[j][3] - input[k][3]); + } + if (e < err) { + err = e; + best = j; + } + } +#else + int best = fxt1_bestcol(vec, n_vect, input[k], n_comp, &err); +#endif + /* add in closest color */ + for (i = 0; i < nc; i++) { + sum[best][i] += input[k][i]; + } + /* mark this vector as used */ + cnt[best]++; + /* accumulate error */ + error += err; + } + + /* check RMS */ + if ((error < LL_RMS_E) || + ((error < lasterror) && ((lasterror - error) < LL_RMS_D))) { + return !0; /* good match */ + } + lasterror = error; + + /* move each vector to the barycenter of its closest colors */ + for (j = 0; j < nv; j++) { + if (cnt[j]) { + float div = 1.0 / cnt[j]; + for (i = 0; i < nc; i++) { + vec[j][i] = div * sum[j][i]; + } + } else { + /* this vec has no samples or is identical with a previous vec */ + int worst = fxt1_worst(vec[j], input, nc, n); + for (i = 0; i < nc; i++) { + vec[j][i] = input[worst][i]; + } + } + } + } + + return 0; /* could not converge fast enough */ +} + + +static void +fxt1_quantize_CHROMA (unsigned long *cc, + unsigned char input[N_TEXELS][MAX_COMP]) +{ + const int n_vect = 4; /* 4 base vectors to find */ + const int n_comp = 3; /* 3 components: R, G, B */ + float vec[MAX_VECT][MAX_COMP]; + int i, j, k; + Fx64 hi; /* high quadword */ + unsigned long lohi, lolo; /* low quadword: hi dword, lo dword */ + + if (fxt1_choose(vec, n_vect, input, n_comp, N_TEXELS) != 0) { + fxt1_lloyd(vec, n_vect, input, n_comp, N_TEXELS); + } + + FX64_MOV32(hi, 4); /* cc-chroma = "010" + unused bit */ + for (j = n_vect - 1; j >= 0; j--) { + for (i = 0; i < n_comp; i++) { + /* add in colors */ + FX64_SHL(hi, 5); + FX64_OR32(hi, (unsigned int)(vec[j][i] / 8.0)); + } + } + ((Fx64 *)cc)[1] = hi; + + lohi = lolo = 0; + /* right microtile */ + for (k = N_TEXELS - 1; k >= N_TEXELS/2; k--) { + lohi <<= 2; + lohi |= fxt1_bestcol(vec, n_vect, input[k], n_comp); + } + /* left microtile */ + for (; k >= 0; k--) { + lolo <<= 2; + lolo |= fxt1_bestcol(vec, n_vect, input[k], n_comp); + } + cc[1] = lohi; + cc[0] = lolo; +} + + +static void +fxt1_quantize_ALPHA0 (unsigned long *cc, + unsigned char input[N_TEXELS][MAX_COMP], + unsigned char reord[N_TEXELS][MAX_COMP], int n) +{ + const int n_vect = 3; /* 3 base vectors to find */ + const int n_comp = 4; /* 4 components: R, G, B, A */ + float vec[MAX_VECT][MAX_COMP]; + int i, j, k; + Fx64 hi; /* high quadword */ + unsigned long lohi, lolo; /* low quadword: hi dword, lo dword */ + + /* the last vector indicates zero */ + for (i = 0; i < n_comp; i++) { + vec[n_vect][i] = 0; + } + + /* the first n texels in reord are guaranteed to be non-zero */ + if (fxt1_choose(vec, n_vect, reord, n_comp, n) != 0) { + fxt1_lloyd(vec, n_vect, reord, n_comp, n); + } + + FX64_MOV32(hi, 6); /* alpha = "011" + lerp = 0 */ + for (j = n_vect - 1; j >= 0; j--) { + /* add in alphas */ + FX64_SHL(hi, 5); + FX64_OR32(hi, (unsigned int)(vec[j][ACOMP] / 8.0)); + } + for (j = n_vect - 1; j >= 0; j--) { + for (i = 0; i < n_comp - 1; i++) { + /* add in colors */ + FX64_SHL(hi, 5); + FX64_OR32(hi, (unsigned int)(vec[j][i] / 8.0)); + } + } + ((Fx64 *)cc)[1] = hi; + + lohi = lolo = 0; + /* right microtile */ + for (k = N_TEXELS - 1; k >= N_TEXELS/2; k--) { + lohi <<= 2; + lohi |= fxt1_bestcol(vec, n_vect + 1, input[k], n_comp); + } + /* left microtile */ + for (; k >= 0; k--) { + lolo <<= 2; + lolo |= fxt1_bestcol(vec, n_vect + 1, input[k], n_comp); + } + cc[1] = lohi; + cc[0] = lolo; +} + + +static void +fxt1_quantize_ALPHA1 (unsigned long *cc, + unsigned char input[N_TEXELS][MAX_COMP]) +{ + const int n_vect = 3; /* highest vector number in each microtile */ + const int n_comp = 4; /* 4 components: R, G, B, A */ + float vec[1 + 1 + 1][MAX_COMP]; /* 1.5 extrema for each sub-block */ + float b, iv[MAX_COMP]; /* interpolation vector */ + int i, j, k; + Fx64 hi; /* high quadword */ + unsigned long lohi, lolo; /* low quadword: hi dword, lo dword */ + + int minSum; + int maxSum; + int minColL = 0, maxColL = 0; + int minColR = 0, maxColR = 0; + int sumL = 0, sumR = 0; + + /* 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). + */ + minSum = 1000; /* big enough */ + maxSum = -1; /* small enough */ + for (k = 0; k < N_TEXELS / 2; k++) { + int sum = 0; + for (i = 0; i < n_comp; i++) { + sum += input[k][i]; + } + if (minSum > sum) { + minSum = sum; + minColL = k; + } + if (maxSum < sum) { + maxSum = sum; + maxColL = k; + } + sumL += sum; + } + minSum = 1000; /* big enough */ + maxSum = -1; /* small enough */ + for (; k < N_TEXELS; k++) { + int sum = 0; + for (i = 0; i < n_comp; i++) { + sum += input[k][i]; + } + if (minSum > sum) { + minSum = sum; + minColR = k; + } + if (maxSum < sum) { + maxSum = sum; + maxColR = k; + } + sumR += sum; + } + + /* choose the common vector (yuck!) */ +{ + int j1, j2; + int v1 = 0, v2 = 0; + float err = 1e9; /* big enough */ + float tv[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */ + for (i = 0; i < n_comp; i++) { + tv[0][i] = input[minColL][i]; + tv[1][i] = input[maxColL][i]; + tv[2][i] = input[minColR][i]; + tv[3][i] = input[maxColR][i]; + } + for (j1 = 0; j1 < 2; j1++) { + for (j2 = 2; j2 < 4; j2++) { + float e = 0; + for (i = 0; i < n_comp; i++) { + e += (tv[j1][i] - tv[j2][i]) * (tv[j1][i] - tv[j2][i]); + } + if (e < err) { + err = e; + v1 = j1; + v2 = j2; + } + } + } + for (i = 0; i < n_comp; i++) { + vec[0][i] = tv[1 - v1][i]; + vec[1][i] = (tv[v1][i] * sumL + tv[v2][i] * sumR) / (sumL + sumR); + vec[2][i] = tv[5 - v2][i]; + } +} + + /* left microtile */ + cc[0] = 0; + if (minColL != maxColL) { + /* compute interpolation vector */ + float d2 = 0; + float rd2; + + for (i = 0; i < n_comp; i++) { + iv[i] = vec[1][i] - vec[0][i]; + d2 += iv[i] * iv[i]; + } + rd2 = (float)n_vect / d2; + b = 0; + for (i = 0; i < n_comp; i++) { + b -= iv[i] * vec[0][i]; + iv[i] *= rd2; + } + b = b * rd2 + 0.5f; + + /* add in texels */ + lolo = 0; + for (k = N_TEXELS / 2 - 1; k >= 0; k--) { + int texel; + /* interpolate color */ + float dot = 0; + for (i = 0; i < n_comp; i++) { + dot += input[k][i] * iv[i]; + } + texel = (int)(dot + b); + if (texel < 0) { + texel = 0; + } else if (texel > n_vect) { + texel = n_vect; + } + /* add in texel */ + lolo <<= 2; + lolo |= texel; + } + + cc[0] = lolo; + } + + /* right microtile */ + cc[1] = 0; + if (minColR != maxColR) { + /* compute interpolation vector */ + float d2 = 0; + float rd2; + + for (i = 0; i < n_comp; i++) { + iv[i] = vec[1][i] - vec[2][i]; + d2 += iv[i] * iv[i]; + } + rd2 = (float)n_vect / d2; + b = 0; + for (i = 0; i < n_comp; i++) { + b -= iv[i] * vec[2][i]; + iv[i] *= rd2; + } + b = b * rd2 + 0.5f; + + /* add in texels */ + lohi = 0; + for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) { + int texel; + /* interpolate color */ + float dot = 0; + for (i = 0; i < n_comp; i++) { + dot += input[k][i] * iv[i]; + } + texel = (int)(dot + b); + if (texel < 0) { + texel = 0; + } else if (texel > n_vect) { + texel = n_vect; + } + /* add in texel */ + lohi <<= 2; + lohi |= texel; + } + + cc[1] = lohi; + } + + FX64_MOV32(hi, 7); /* alpha = "011" + lerp = 1 */ + for (j = n_vect - 1; j >= 0; j--) { + /* add in alphas */ + FX64_SHL(hi, 5); + FX64_OR32(hi, (unsigned int)(vec[j][ACOMP] / 8.0)); + } + for (j = n_vect - 1; j >= 0; j--) { + for (i = 0; i < n_comp - 1; i++) { + /* add in colors */ + FX64_SHL(hi, 5); + FX64_OR32(hi, (unsigned int)(vec[j][i] / 8.0)); + } + } + ((Fx64 *)cc)[1] = hi; +} + + +static void +fxt1_quantize_HI (unsigned long *cc, + unsigned char input[N_TEXELS][MAX_COMP], + unsigned char reord[N_TEXELS][MAX_COMP], int n) +{ + const int n_vect = 6; /* highest vector number */ + const int n_comp = 3; /* 3 components: R, G, B */ + float b = 0.0; /* phoudoin: silent compiler! */ + float iv[MAX_COMP]; /* interpolation vector */ + int i, k; + unsigned long hihi; /* high quadword: hi dword */ + + int minSum = 1000; /* big enough */ + int maxSum = -1; /* small enough */ + int minCol = 0; /* phoudoin: silent compiler! */ + int maxCol = 0; /* phoudoin: silent compiler! */ + + /* Our solution here is to find the darkest and brightest colors in + * the 8x4 tile and use those as the two representative colors. + * There are probably better algorithms to use (histogram-based). + */ + for (k = 0; k < n; k++) { + int sum = 0; + for (i = 0; i < n_comp; i++) { + sum += reord[k][i]; + } + if (minSum > sum) { + minSum = sum; + minCol = k; + } + if (maxSum < sum) { + maxSum = sum; + maxCol = k; + } + } + + hihi = 0; /* cc-hi = "00" */ + for (i = 0; i < n_comp; i++) { + /* add in colors */ + hihi <<= 5; + hihi |= reord[maxCol][i] >> 3; + } + for (i = 0; i < n_comp; i++) { + /* add in colors */ + hihi <<= 5; + hihi |= reord[minCol][i] >> 3; + } + cc[3] = hihi; + cc[0] = cc[1] = cc[2] = 0; + + /* compute interpolation vector */ + if (minCol != maxCol) { + float d2 = 0; + float rd2; + + for (i = 0; i < n_comp; i++) { + iv[i] = reord[maxCol][i] - reord[minCol][i]; + d2 += iv[i] * iv[i]; + } + rd2 = (float)n_vect / d2; + b = 0; + for (i = 0; i < n_comp; i++) { + b -= iv[i] * reord[minCol][i]; + iv[i] *= rd2; + } + b = b * rd2 + 0.5f; + } + + /* add in texels */ + for (k = N_TEXELS - 1; k >= 0; k--) { + int t = k * 3; + unsigned long *kk = (unsigned long *)((unsigned long)cc + t / 8); + int texel = n_vect + 1; /* transparent black */ + + if (!ISTBLACK(input[k])) { + if (minCol != maxCol) { + /* interpolate color */ + float dot = 0; + for (i = 0; i < n_comp; i++) { + dot += input[k][i] * iv[i]; + } + texel = (int)(dot + b); + if (texel < 0) { + texel = 0; + } else if (texel > n_vect) { + texel = n_vect; + } + /* add in texel */ + kk[0] |= texel << (t & 7); + } + } else { + /* add in texel */ + kk[0] |= texel << (t & 7); + } + } +} + + +static void +fxt1_quantize_MIXED1 (unsigned long *cc, + unsigned char input[N_TEXELS][MAX_COMP]) +{ + const int n_vect = 2; /* highest vector number in each microtile */ + const int n_comp = 3; /* 3 components: R, G, B */ + unsigned char vec[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */ + float b, iv[MAX_COMP]; /* interpolation vector */ + int i, j, k; + Fx64 hi; /* high quadword */ + unsigned long lohi, lolo; /* low quadword: hi dword, lo dword */ + + int minSum; + int maxSum; + int minColL = 0, maxColL = -1; + int minColR = 0, maxColR = -1; + + /* 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). + */ + minSum = 1000; /* big enough */ + maxSum = -1; /* small enough */ + for (k = 0; k < N_TEXELS / 2; k++) { + if (!ISTBLACK(input[k])) { + int sum = 0; + for (i = 0; i < n_comp; i++) { + sum += input[k][i]; + } + if (minSum > sum) { + minSum = sum; + minColL = k; + } + if (maxSum < sum) { + maxSum = sum; + maxColL = k; + } + } + } + minSum = 1000; /* big enough */ + maxSum = -1; /* small enough */ + for (; k < N_TEXELS; k++) { + if (!ISTBLACK(input[k])) { + int sum = 0; + for (i = 0; i < n_comp; i++) { + sum += input[k][i]; + } + if (minSum > sum) { + minSum = sum; + minColR = k; + } + if (maxSum < sum) { + maxSum = sum; + maxColR = k; + } + } + } + + /* left microtile */ + if (maxColL == -1) { + /* all transparent black */ + cc[0] = -1; + for (i = 0; i < n_comp; i++) { + vec[0][i] = 0; + vec[1][i] = 0; + } + } else { + cc[0] = 0; + for (i = 0; i < n_comp; i++) { + vec[0][i] = input[minColL][i]; + vec[1][i] = input[maxColL][i]; + } + if (minColL != maxColL) { + /* compute interpolation vector */ + float d2 = 0; + float rd2; + + for (i = 0; i < n_comp; i++) { + iv[i] = vec[1][i] - vec[0][i]; + d2 += iv[i] * iv[i]; + } + rd2 = (float)n_vect / d2; + b = 0; + for (i = 0; i < n_comp; i++) { + b -= iv[i] * vec[0][i]; + iv[i] *= rd2; + } + b = b * rd2 + 0.5f; + + /* add in texels */ + lolo = 0; + for (k = N_TEXELS / 2 - 1; k >= 0; k--) { + int texel = n_vect + 1; /* transparent black */ + if (!ISTBLACK(input[k])) { + /* interpolate color */ + float dot = 0; + for (i = 0; i < n_comp; i++) { + dot += input[k][i] * iv[i]; + } + texel = (int)(dot + b); + if (texel < 0) { + texel = 0; + } else if (texel > n_vect) { + texel = n_vect; + } + } + /* add in texel */ + lolo <<= 2; + lolo |= texel; + } + cc[0] = lolo; + } + } + + /* right microtile */ + if (maxColR == -1) { + /* all transparent black */ + cc[1] = -1; + for (i = 0; i < n_comp; i++) { + vec[2][i] = 0; + vec[3][i] = 0; + } + } else { + cc[1] = 0; + for (i = 0; i < n_comp; i++) { + vec[2][i] = input[minColR][i]; + vec[3][i] = input[maxColR][i]; + } + if (minColR != maxColR) { + /* compute interpolation vector */ + float d2 = 0; + float rd2; + + for (i = 0; i < n_comp; i++) { + iv[i] = vec[3][i] - vec[2][i]; + d2 += iv[i] * iv[i]; + } + rd2 = (float)n_vect / d2; + b = 0; + for (i = 0; i < n_comp; i++) { + b -= iv[i] * vec[2][i]; + iv[i] *= rd2; + } + b = b * rd2 + 0.5f; + + /* add in texels */ + lohi = 0; + for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) { + int texel = n_vect + 1; /* transparent black */ + if (!ISTBLACK(input[k])) { + /* interpolate color */ + float dot = 0; + for (i = 0; i < n_comp; i++) { + dot += input[k][i] * iv[i]; + } + texel = (int)(dot + b); + if (texel < 0) { + texel = 0; + } else if (texel > n_vect) { + texel = n_vect; + } + } + /* add in texel */ + lohi <<= 2; + lohi |= texel; + } + cc[1] = lohi; + } + } + + FX64_MOV32(hi, 9 | (vec[3][GCOMP] & 4) | ((vec[1][GCOMP] >> 1) & 2)); /* chroma = "1" */ + for (j = 2 * 2 - 1; j >= 0; j--) { + for (i = 0; i < n_comp; i++) { + /* add in colors */ + FX64_SHL(hi, 5); + FX64_OR32(hi, vec[j][i] >> 3); + } + } + ((Fx64 *)cc)[1] = hi; +} + + +static void +fxt1_quantize_MIXED0 (unsigned long *cc, + unsigned char input[N_TEXELS][MAX_COMP]) +{ + const int n_vect = 3; /* highest vector number in each microtile */ + const int n_comp = 3; /* 3 components: R, G, B */ + unsigned char vec[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */ + float b, iv[MAX_COMP]; /* interpolation vector */ + int i, j, k; + Fx64 hi; /* high quadword */ + unsigned long lohi, lolo; /* low quadword: hi dword, lo dword */ + + int minColL = 0, maxColL = 0; + int minColR = 0, maxColR = 0; +#if 0 + int minSum; + int maxSum; + + /* 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). + */ + minSum = 1000; /* big enough */ + maxSum = -1; /* small enough */ + for (k = 0; k < N_TEXELS / 2; k++) { + int sum = 0; + for (i = 0; i < n_comp; i++) { + sum += input[k][i]; + } + if (minSum > sum) { + minSum = sum; + minColL = k; + } + if (maxSum < sum) { + maxSum = sum; + maxColL = k; + } + } + minSum = 1000; /* big enough */ + maxSum = -1; /* small enough */ + for (; k < N_TEXELS; k++) { + int sum = 0; + for (i = 0; i < n_comp; i++) { + sum += input[k][i]; + } + if (minSum > sum) { + minSum = sum; + minColR = k; + } + if (maxSum < sum) { + maxSum = sum; + maxColR = k; + } + } +#else + int minVal; + int maxVal; + int maxVarL = fxt1_variance(NULL, input, n_comp, N_TEXELS / 2); + int maxVarR = fxt1_variance(NULL, &input[N_TEXELS / 2], n_comp, N_TEXELS / 2); + + /* Scan the channel with max variance for lo & hi + * and use those as the two representative colors. + */ + minVal = 1000; /* big enough */ + maxVal = -1; /* small enough */ + for (k = 0; k < N_TEXELS / 2; k++) { + int t = input[k][maxVarL]; + if (minVal > t) { + minVal = t; + minColL = k; + } + if (maxVal < t) { + maxVal = t; + maxColL = k; + } + } + minVal = 1000; /* big enough */ + maxVal = -1; /* small enough */ + for (; k < N_TEXELS; k++) { + int t = input[k][maxVarR]; + if (minVal > t) { + minVal = t; + minColR = k; + } + if (maxVal < t) { + maxVal = t; + maxColR = k; + } + } +#endif + + /* left microtile */ + cc[0] = 0; + for (i = 0; i < n_comp; i++) { + vec[0][i] = input[minColL][i]; + vec[1][i] = input[maxColL][i]; + } + if (minColL != maxColL) { + /* compute interpolation vector */ + float d2 = 0; + float rd2; + + for (i = 0; i < n_comp; i++) { + iv[i] = vec[1][i] - vec[0][i]; + d2 += iv[i] * iv[i]; + } + rd2 = (float)n_vect / d2; + b = 0; + for (i = 0; i < n_comp; i++) { + b -= iv[i] * vec[0][i]; + iv[i] *= rd2; + } + b = b * rd2 + 0.5f; + + /* add in texels */ + lolo = 0; + for (k = N_TEXELS / 2 - 1; k >= 0; k--) { + int texel; + /* interpolate color */ + float dot = 0; + for (i = 0; i < n_comp; i++) { + dot += input[k][i] * iv[i]; + } + texel = (int)(dot + b); + if (texel < 0) { + texel = 0; + } else if (texel > n_vect) { + texel = n_vect; + } + /* add in texel */ + lolo <<= 2; + lolo |= texel; + } + + /* funky encoding for LSB of green */ + if ((int)((lolo >> 1) & 1) != (((vec[1][GCOMP] ^ vec[0][GCOMP]) >> 2) & 1)) { + for (i = 0; i < n_comp; i++) { + vec[1][i] = input[minColL][i]; + vec[0][i] = input[maxColL][i]; + } + lolo = ~lolo; + } + + cc[0] = lolo; + } + + /* right microtile */ + cc[1] = 0; + for (i = 0; i < n_comp; i++) { + vec[2][i] = input[minColR][i]; + vec[3][i] = input[maxColR][i]; + } + if (minColR != maxColR) { + /* compute interpolation vector */ + float d2 = 0; + float rd2; + + for (i = 0; i < n_comp; i++) { + iv[i] = vec[3][i] - vec[2][i]; + d2 += iv[i] * iv[i]; + } + rd2 = (float)n_vect / d2; + b = 0; + for (i = 0; i < n_comp; i++) { + b -= iv[i] * vec[2][i]; + iv[i] *= rd2; + } + b = b * rd2 + 0.5f; + + /* add in texels */ + lohi = 0; + for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) { + int texel; + /* interpolate color */ + float dot = 0; + for (i = 0; i < n_comp; i++) { + dot += input[k][i] * iv[i]; + } + texel = (int)(dot + b); + if (texel < 0) { + texel = 0; + } else if (texel > n_vect) { + texel = n_vect; + } + /* add in texel */ + lohi <<= 2; + lohi |= texel; + } + + /* funky encoding for LSB of green */ + if ((int)((lohi >> 1) & 1) != (((vec[3][GCOMP] ^ vec[2][GCOMP]) >> 2) & 1)) { + for (i = 0; i < n_comp; i++) { + vec[3][i] = input[minColR][i]; + vec[2][i] = input[maxColR][i]; + } + lohi = ~lohi; + } + + cc[1] = lohi; + } + + FX64_MOV32(hi, 8 | (vec[3][GCOMP] & 4) | ((vec[1][GCOMP] >> 1) & 2)); /* chroma = "1" */ + for (j = 2 * 2 - 1; j >= 0; j--) { + for (i = 0; i < n_comp; i++) { + /* add in colors */ + FX64_SHL(hi, 5); + FX64_OR32(hi, vec[j][i] >> 3); + } + } + ((Fx64 *)cc)[1] = hi; +} + + +static void +fxt1_quantize (unsigned long *cc, const unsigned char *lines[], int comps) +{ + int trualpha; + unsigned char reord[N_TEXELS][MAX_COMP]; + + unsigned char input[N_TEXELS][MAX_COMP]; + int i, k, l; + + memset(input, -1, sizeof(input)); + + /* 8 texels each line */ + 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]++; + } + } + for (; k < 8; k++) { + for (i = 0; i < comps; i++) { + input[k + l * 4 + 12][i] = *lines[l]++; + } + } + } + + /* block layout: + * 00, 01, 02, 03, 08, 09, 0a, 0b + * 10, 11, 12, 13, 18, 19, 1a, 1b + * 04, 05, 06, 07, 0c, 0d, 0e, 0f + * 14, 15, 16, 17, 1c, 1d, 1e, 1f + */ + + /* [dBorca] + * stupidity flows forth from this + */ + l = N_TEXELS; + trualpha = 0; + if (comps == 4) { + /* skip all transparent black texels */ + l = 0; + for (k = 0; k < N_TEXELS; k++) { + /* test all components against 0 */ + if (!ISTBLACK(input[k])) { + /* texel is not transparent black */ + COPY_4UBV(reord[l], input[k]); + if (reord[l][ACOMP] < (255 - ALPHA_TS)) { + /* non-opaque texel */ + trualpha = !0; + } + l++; + } + } + } + +#if 0 + if (trualpha) { + fxt1_quantize_ALPHA0(cc, input, reord, l); + } else if (l == 0) { + cc[0] = cc[1] = cc[2] = -1; + cc[3] = 0; + } else if (l < N_TEXELS) { + fxt1_quantize_HI(cc, input, reord, l); + } else { + fxt1_quantize_CHROMA(cc, input); + } + (void)fxt1_quantize_ALPHA1; + (void)fxt1_quantize_MIXED1; + (void)fxt1_quantize_MIXED0; +#else + if (trualpha) { + fxt1_quantize_ALPHA1(cc, input); + } else if (l == 0) { + cc[0] = cc[1] = cc[2] = -1; + cc[3] = 0; + } else if (l < N_TEXELS) { + fxt1_quantize_MIXED1(cc, input); + } else { + fxt1_quantize_MIXED0(cc, input); + } + (void)fxt1_quantize_ALPHA0; + (void)fxt1_quantize_HI; + (void)fxt1_quantize_CHROMA; +#endif +} + + +int +fxt1_encode (GLcontext *ctx, + unsigned int width, unsigned int height, + int srcFormat, + const void *source, int srcRowStride, + void *dest, int destRowStride) +{ + const int comps = (srcFormat == GL_RGB) ? 3 : 4; + unsigned int x, y; + const unsigned char *data; + unsigned long *encoded = dest; + GLubyte *newSource = NULL; + + (void) ctx; + + /* + * Rescale image if width is less than 8 or height is less than 4. + */ + if (width < 8 || height < 4) { + GLint newWidth = (width + 7) & ~7; + GLint newHeight = (height + 3) & ~3; + newSource = MALLOC(comps * newWidth * newHeight * sizeof(GLchan)); + _mesa_upscale_teximage2d(width, height, newWidth, newHeight, + comps, source, srcRowStride, newSource); + source = newSource; + width = newWidth; + height = newHeight; + srcRowStride = comps * newWidth; + } + + data = source; + destRowStride = (destRowStride - width * 2) / 4; + for (y = 0; y < height; y += 4) { + unsigned int offs = 0 + (y + 0) * srcRowStride; + for (x = 0; x < width; x += 8) { + const unsigned char *lines[4]; + lines[0] = &data[offs]; + lines[1] = lines[0] + srcRowStride; + lines[2] = lines[1] + srcRowStride; + lines[3] = lines[2] + srcRowStride; + offs += 8 * comps; + fxt1_quantize(encoded, lines, comps); + /* 128 bits per 8x4 block = 4bpp */ + encoded += 4; + } + encoded += destRowStride; + } + + if (newSource != NULL) { + FREE(newSource); + } + + return 0; +} + + +/***************************************************************************\ + * FXT1 decoder + * + * The decoder is based on GL_3DFX_texture_compression_FXT1 + * specification and serves as a concept for the encoder. +\***************************************************************************/ + + +/* lookup table for scaling 5 bit colors up to 8 bits */ +static unsigned char _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 unsigned char _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) ((cc)[(which) / 32] >> ((which) & 31)) +#define UP5(c) _rgb_scale_5[(c) & 31] +#define UP6(c, b) _rgb_scale_6[(((c) & 31) << 1) | ((b) & 1)] +#define LERP(n, t, c0, c1) (((n) - (t)) * (c0) + (t) * (c1) + (n) / 2) / (n) +#define ZERO_4UBV(v) *((unsigned long *)(v)) = 0 + + +static void +fxt1_decode_1HI (unsigned long code, int t, unsigned char *rgba) +{ + const unsigned long *cc; + + t *= 3; + cc = (unsigned long *)(code + t / 8); + t = (cc[0] >> (t & 7)) & 7; + + if (t == 7) { + ZERO_4UBV(rgba); + } else { + cc = (unsigned long *)(code + 12); + if (t == 0) { + rgba[BCOMP] = UP5(CC_SEL(cc, 0)); + rgba[GCOMP] = UP5(CC_SEL(cc, 5)); + rgba[RCOMP] = UP5(CC_SEL(cc, 10)); + } else if (t == 6) { + rgba[BCOMP] = UP5(CC_SEL(cc, 15)); + rgba[GCOMP] = UP5(CC_SEL(cc, 20)); + rgba[RCOMP] = UP5(CC_SEL(cc, 25)); + } else { + rgba[BCOMP] = LERP(6, t, UP5(CC_SEL(cc, 0)), UP5(CC_SEL(cc, 15))); + rgba[GCOMP] = LERP(6, t, UP5(CC_SEL(cc, 5)), UP5(CC_SEL(cc, 20))); + rgba[RCOMP] = LERP(6, t, UP5(CC_SEL(cc, 10)), UP5(CC_SEL(cc, 25))); + } + rgba[ACOMP] = 255; + } +} + + +static void +fxt1_decode_1CHROMA (unsigned long code, int t, unsigned char *rgba) +{ + const unsigned long *cc; + unsigned long kk; + + cc = (unsigned long *)code; + if (t & 16) { + cc++; + t &= 15; + } + t = (cc[0] >> (t * 2)) & 3; + + t *= 15; + cc = (unsigned long *)(code + 8 + t / 8); + kk = cc[0] >> (t & 7); + rgba[BCOMP] = UP5(kk); + rgba[GCOMP] = UP5(kk >> 5); + rgba[RCOMP] = UP5(kk >> 10); + rgba[ACOMP] = 255; +} + + +static void +fxt1_decode_1MIXED (unsigned long code, int t, unsigned char *rgba) +{ + const unsigned long *cc; + unsigned int col[2][3]; + int glsb, selb; + + cc = (unsigned long *)code; + if (t & 16) { + t &= 15; + t = (cc[1] >> (t * 2)) & 3; + /* col 2 */ + col[0][BCOMP] = (*(unsigned long *)(code + 11)) >> 6; + col[0][GCOMP] = CC_SEL(cc, 99); + col[0][RCOMP] = CC_SEL(cc, 104); + /* col 3 */ + col[1][BCOMP] = CC_SEL(cc, 109); + col[1][GCOMP] = CC_SEL(cc, 114); + col[1][RCOMP] = CC_SEL(cc, 119); + glsb = CC_SEL(cc, 126); + selb = CC_SEL(cc, 33); + } else { + t = (cc[0] >> (t * 2)) & 3; + /* col 0 */ + col[0][BCOMP] = CC_SEL(cc, 64); + col[0][GCOMP] = CC_SEL(cc, 69); + col[0][RCOMP] = CC_SEL(cc, 74); + /* col 1 */ + col[1][BCOMP] = CC_SEL(cc, 79); + col[1][GCOMP] = CC_SEL(cc, 84); + col[1][RCOMP] = CC_SEL(cc, 89); + glsb = CC_SEL(cc, 125); + selb = CC_SEL(cc, 1); + } + + if (CC_SEL(cc, 124) & 1) { + /* alpha[0] == 1 */ + + if (t == 3) { + ZERO_4UBV(rgba); + } else { + if (t == 0) { + rgba[BCOMP] = UP5(col[0][BCOMP]); + rgba[GCOMP] = UP5(col[0][GCOMP]); + rgba[RCOMP] = UP5(col[0][RCOMP]); + } else if (t == 2) { + rgba[BCOMP] = UP5(col[1][BCOMP]); + rgba[GCOMP] = UP6(col[1][GCOMP], glsb); + rgba[RCOMP] = UP5(col[1][RCOMP]); + } else { + rgba[BCOMP] = (UP5(col[0][BCOMP]) + UP5(col[1][BCOMP])) / 2; + rgba[GCOMP] = (UP5(col[0][GCOMP]) + UP6(col[1][GCOMP], glsb)) / 2; + rgba[RCOMP] = (UP5(col[0][RCOMP]) + UP5(col[1][RCOMP])) / 2; + } + rgba[ACOMP] = 255; + } + } else { + /* alpha[0] == 0 */ + + if (t == 0) { + rgba[BCOMP] = UP5(col[0][BCOMP]); + rgba[GCOMP] = UP6(col[0][GCOMP], glsb ^ selb); + rgba[RCOMP] = UP5(col[0][RCOMP]); + } else if (t == 3) { + rgba[BCOMP] = UP5(col[1][BCOMP]); + rgba[GCOMP] = UP6(col[1][GCOMP], glsb); + rgba[RCOMP] = UP5(col[1][RCOMP]); + } else { + rgba[BCOMP] = LERP(3, t, UP5(col[0][BCOMP]), UP5(col[1][BCOMP])); + rgba[GCOMP] = LERP(3, t, UP6(col[0][GCOMP], glsb ^ selb), + UP6(col[1][GCOMP], glsb)); + rgba[RCOMP] = LERP(3, t, UP5(col[0][RCOMP]), UP5(col[1][RCOMP])); + } + rgba[ACOMP] = 255; + } +} + + +static void +fxt1_decode_1ALPHA (unsigned long code, int t, unsigned char *rgba) +{ + const unsigned long *cc; + + cc = (unsigned long *)code; + if (CC_SEL(cc, 124) & 1) { + /* lerp == 1 */ + unsigned int col0[4]; + + if (t & 16) { + t &= 15; + t = (cc[1] >> (t * 2)) & 3; + /* col 2 */ + col0[BCOMP] = (*(unsigned long *)(code + 11)) >> 6; + col0[GCOMP] = CC_SEL(cc, 99); + col0[RCOMP] = CC_SEL(cc, 104); + col0[ACOMP] = CC_SEL(cc, 119); + } else { + t = (cc[0] >> (t * 2)) & 3; + /* col 0 */ + col0[BCOMP] = CC_SEL(cc, 64); + col0[GCOMP] = CC_SEL(cc, 69); + col0[RCOMP] = CC_SEL(cc, 74); + col0[ACOMP] = CC_SEL(cc, 109); + } + + if (t == 0) { + rgba[BCOMP] = UP5(col0[BCOMP]); + rgba[GCOMP] = UP5(col0[GCOMP]); + rgba[RCOMP] = UP5(col0[RCOMP]); + rgba[ACOMP] = UP5(col0[ACOMP]); + } else if (t == 3) { + rgba[BCOMP] = UP5(CC_SEL(cc, 79)); + rgba[GCOMP] = UP5(CC_SEL(cc, 84)); + rgba[RCOMP] = UP5(CC_SEL(cc, 89)); + rgba[ACOMP] = UP5(CC_SEL(cc, 114)); + } else { + rgba[BCOMP] = LERP(3, t, UP5(col0[BCOMP]), UP5(CC_SEL(cc, 79))); + rgba[GCOMP] = LERP(3, t, UP5(col0[GCOMP]), UP5(CC_SEL(cc, 84))); + rgba[RCOMP] = LERP(3, t, UP5(col0[RCOMP]), UP5(CC_SEL(cc, 89))); + rgba[ACOMP] = LERP(3, t, UP5(col0[ACOMP]), UP5(CC_SEL(cc, 114))); + } + } else { + /* lerp == 0 */ + + if (t & 16) { + cc++; + t &= 15; + } + t = (cc[0] >> (t * 2)) & 3; + + if (t == 3) { + ZERO_4UBV(rgba); + } else { + unsigned long kk; + cc = (unsigned long *)code; + rgba[ACOMP] = UP5(cc[3] >> (t * 5 + 13)); + t *= 15; + cc = (unsigned long *)(code + 8 + t / 8); + kk = cc[0] >> (t & 7); + rgba[BCOMP] = UP5(kk); + rgba[GCOMP] = UP5(kk >> 5); + rgba[RCOMP] = UP5(kk >> 10); + } + } +} + + +void +fxt1_decode_1 (const void *texture, int width, + int i, int j, unsigned char *rgba) +{ + static void (*decode_1[]) (unsigned long, int, unsigned char *) = { + fxt1_decode_1HI, /* cc-high = "00?" */ + fxt1_decode_1HI, /* cc-high = "00?" */ + fxt1_decode_1CHROMA, /* cc-chroma = "010" */ + fxt1_decode_1ALPHA, /* alpha = "011" */ + fxt1_decode_1MIXED, /* mixed = "1??" */ + fxt1_decode_1MIXED, /* mixed = "1??" */ + fxt1_decode_1MIXED, /* mixed = "1??" */ + fxt1_decode_1MIXED /* mixed = "1??" */ + }; + + unsigned long code = (unsigned long)texture + + ((j / 4) * (width / 8) + (i / 8)) * 16; + int mode = CC_SEL((unsigned long *)code, 125); + int t = i & 7; + + if (t & 4) { + t += 12; + } + t += (j & 3) * 4; + + decode_1[mode](code, t, rgba); +} -- cgit