xserver and mesa git update 28-12-2010

1 files changed, 1650 insertions, 1653 deletions

diff --git a/mesalib/src/mesa/main/texcompress_fxt1.c b/mesalib/src/mesa/main/texcompress_fxt1.c
index c8b45bd3a..e6dd7f364 100644
--- a/mesalib/src/mesa/main/texcompress_fxt1.c
+++ b/mesalib/src/mesa/main/texcompress_fxt1.c
@@ -1,1653 +1,1650 @@
-/*
- * Mesa 3-D graphics library
- * Version:  7.1
- *
- * Copyright (C) 1999-2008  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 "convolve.h"
-#include "image.h"
-#include "macros.h"
-#include "mipmap.h"
-#include "texcompress.h"
-#include "texcompress_fxt1.h"
-#include "texstore.h"
-
-
-#if FEATURE_texture_fxt1
-
-
-static void
-fxt1_encode (GLuint width, GLuint height, GLint comps,
-             const void *source, GLint srcRowStride,
-             void *dest, GLint destRowStride);
-
-void
-fxt1_decode_1 (const void *texture, GLint stride,
-               GLint i, GLint j, GLchan *rgba);
-
-
-/**
- * Store user's image in rgb_fxt1 format.
- */
-GLboolean
-_mesa_texstore_rgb_fxt1(TEXSTORE_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_FORMAT_RGB_FXT1);
-   ASSERT(dstXoffset % 8 == 0);
-   ASSERT(dstYoffset % 4 == 0);
-   ASSERT(dstZoffset     == 0);
-   (void) dstZoffset;
-   (void) dstImageOffsets;
-
-   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,
-                                             _mesa_get_format_base_format(dstFormat),
-                                             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,
-                                        dstFormat,
-                                        texWidth, (GLubyte *) dstAddr);
-
-   fxt1_encode(srcWidth, srcHeight, 3, pixels, srcRowStride,
-               dst, dstRowStride);
-
-   if (tempImage)
-      free((void*) tempImage);
-
-   return GL_TRUE;
-}
-
-
-/**
- * Store user's image in rgba_fxt1 format.
- */
-GLboolean
-_mesa_texstore_rgba_fxt1(TEXSTORE_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_FORMAT_RGBA_FXT1);
-   ASSERT(dstXoffset % 8 == 0);
-   ASSERT(dstYoffset % 4 == 0);
-   ASSERT(dstZoffset     == 0);
-   (void) dstZoffset;
-   (void) dstImageOffsets;
-
-   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,
-                                             _mesa_get_format_base_format(dstFormat),
-                                             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,
-                                        dstFormat,
-                                        texWidth, (GLubyte *) dstAddr);
-
-   fxt1_encode(srcWidth, srcHeight, 4, pixels, srcRowStride,
-               dst, dstRowStride);
-
-   if (tempImage)
-      free((void*) tempImage);
-
-   return GL_TRUE;
-}
-
-
-void
-_mesa_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->RowStride, 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]);
-}
-
-
-void
-_mesa_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->RowStride, 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] = 1.0F;
-}
-
-
-
-/***************************************************************************\
- * 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 highly UNoptimized;
- * moreover, it is sub-optimal due to initial conditions passed
- * to Lloyd's algorithm (the interpolation modes are even 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) (*((GLuint *)(v)) == 0)
-
-
-/*
- * Define a 64-bit unsigned integer type and macros
- */
-#if 1
-
-#define FX64_NATIVE 1
-
-typedef uint64_t Fx64;
-
-#define FX64_MOV32(a, b) a = b
-#define FX64_OR32(a, b)  a |= b
-#define FX64_SHL(a, c)   a <<= c
-
-#else
-
-#define FX64_NATIVE 0
-
-typedef struct {
-   GLuint 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
-
-
-#define F(i) (GLfloat)1 /* can be used to obtain an oblong metric: 0.30 / 0.59 / 0.11 */
-#define SAFECDOT 1 /* for paranoids */
-
-#define MAKEIVEC(NV, NC, IV, B, V0, V1)  \
-   do {                                  \
-      /* compute interpolation vector */ \
-      GLfloat d2 = 0.0F;                 \
-      GLfloat rd2;                       \
-                                         \
-      for (i = 0; i < NC; i++) {         \
-         IV[i] = (V1[i] - V0[i]) * F(i); \
-         d2 += IV[i] * IV[i];            \
-      }                                  \
-      rd2 = (GLfloat)NV / d2;            \
-      B = 0;                             \
-      for (i = 0; i < NC; i++) {         \
-         IV[i] *= F(i);                  \
-         B -= IV[i] * V0[i];             \
-         IV[i] *= rd2;                   \
-      }                                  \
-      B = B * rd2 + 0.5f;                \
-   } while (0)
-
-#define CALCCDOT(TEXEL, NV, NC, IV, B, V)\
-   do {                                  \
-      GLfloat dot = 0.0F;                \
-      for (i = 0; i < NC; i++) {         \
-         dot += V[i] * IV[i];            \
-      }                                  \
-      TEXEL = (GLint)(dot + B);          \
-      if (SAFECDOT) {                    \
-         if (TEXEL < 0) {                \
-            TEXEL = 0;                   \
-         } else if (TEXEL > NV) {        \
-            TEXEL = NV;                  \
-         }                               \
-      }                                  \
-   } while (0)
-
-
-static GLint
-fxt1_bestcol (GLfloat vec[][MAX_COMP], GLint nv,
-              GLubyte input[MAX_COMP], GLint nc)
-{
-   GLint i, j, best = -1;
-   GLfloat err = 1e9; /* big enough */
-
-   for (j = 0; j < nv; j++) {
-      GLfloat e = 0.0F;
-      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 GLint
-fxt1_worst (GLfloat vec[MAX_COMP],
-            GLubyte input[N_TEXELS][MAX_COMP], GLint nc, GLint n)
-{
-   GLint i, k, worst = -1;
-   GLfloat err = -1.0F; /* small enough */
-
-   for (k = 0; k < n; k++) {
-      GLfloat e = 0.0F;
-      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 GLint
-fxt1_variance (GLdouble variance[MAX_COMP],
-               GLubyte input[N_TEXELS][MAX_COMP], GLint nc, GLint n)
-{
-   GLint i, k, best = 0;
-   GLint sx, sx2;
-   GLdouble var, maxvar = -1; /* small enough */
-   GLdouble teenth = 1.0 / n;
-
-   for (i = 0; i < nc; i++) {
-      sx = sx2 = 0;
-      for (k = 0; k < n; k++) {
-         GLint 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 GLint
-fxt1_choose (GLfloat vec[][MAX_COMP], GLint nv,
-             GLubyte input[N_TEXELS][MAX_COMP], GLint nc, GLint n)
-{
-#if 0
-   /* Choose colors from a grid.
-    */
-   GLint i, j;
-
-   for (j = 0; j < nv; j++) {
-      GLint 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).
-    */
-   GLint i, j, k;
-   GLint minSum = 2000; /* big enough */
-   GLint maxSum = -1; /* small enough */
-   GLint minCol = 0; /* phoudoin: silent compiler! */
-   GLint maxCol = 0; /* phoudoin: silent compiler! */
-
-   struct {
-      GLint flag;
-      GLint key;
-      GLint freq;
-      GLint idx;
-   } hist[N_TEXELS];
-   GLint lenh = 0;
-
-   memset(hist, 0, sizeof(hist));
-
-   for (k = 0; k < n; k++) {
-      GLint l;
-      GLint key = 0;
-      GLint 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] = (GLfloat)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) / (GLfloat)(nv - 1);
-      }
-   }
-#endif
-
-   return !0;
-}
-
-
-static GLint
-fxt1_lloyd (GLfloat vec[][MAX_COMP], GLint nv,
-            GLubyte input[N_TEXELS][MAX_COMP], GLint nc, GLint 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 its 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
-    */
-
-   GLint sum[MAX_VECT][MAX_COMP]; /* used to accumulate closest texels */
-   GLint cnt[MAX_VECT]; /* how many times a certain vector was chosen */
-   GLfloat error, lasterror = 1e9;
-
-   GLint 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
-         GLint best = -1;
-         GLfloat err = 1e9; /* big enough */
-         /* determine best vector */
-         for (j = 0; j < nv; j++) {
-            GLfloat 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
-         GLint best = fxt1_bestcol(vec, nv, input[k], nc, &err);
-#endif
-         assert(best >= 0);
-         /* 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]) {
-            GLfloat div = 1.0F / 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 */
-            GLint 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 (GLuint *cc,
-                      GLubyte input[N_TEXELS][MAX_COMP])
-{
-   const GLint n_vect = 4; /* 4 base vectors to find */
-   const GLint n_comp = 3; /* 3 components: R, G, B */
-   GLfloat vec[MAX_VECT][MAX_COMP];
-   GLint i, j, k;
-   Fx64 hi; /* high quadword */
-   GLuint 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, (GLuint)(vec[j][i] / 8.0F));
-      }
-   }
-   ((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 (GLuint *cc,
-                      GLubyte input[N_TEXELS][MAX_COMP],
-                      GLubyte reord[N_TEXELS][MAX_COMP], GLint n)
-{
-   const GLint n_vect = 3; /* 3 base vectors to find */
-   const GLint n_comp = 4; /* 4 components: R, G, B, A */
-   GLfloat vec[MAX_VECT][MAX_COMP];
-   GLint i, j, k;
-   Fx64 hi; /* high quadword */
-   GLuint 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, (GLuint)(vec[j][ACOMP] / 8.0F));
-   }
-   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, (GLuint)(vec[j][i] / 8.0F));
-      }
-   }
-   ((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 (GLuint *cc,
-                      GLubyte input[N_TEXELS][MAX_COMP])
-{
-   const GLint n_vect = 3; /* highest vector number in each microtile */
-   const GLint n_comp = 4; /* 4 components: R, G, B, A */
-   GLfloat vec[1 + 1 + 1][MAX_COMP]; /* 1.5 extrema for each sub-block */
-   GLfloat b, iv[MAX_COMP]; /* interpolation vector */
-   GLint i, j, k;
-   Fx64 hi; /* high quadword */
-   GLuint lohi, lolo; /* low quadword: hi dword, lo dword */
-
-   GLint minSum;
-   GLint maxSum;
-   GLint minColL = 0, maxColL = 0;
-   GLint minColR = 0, maxColR = 0;
-   GLint sumL = 0, sumR = 0;
-   GLint nn_comp;
-   /* 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).
-    */
-   nn_comp = n_comp;
-   while ((minColL == maxColL) && nn_comp) {
-       minSum = 2000; /* big enough */
-       maxSum = -1; /* small enough */
-       for (k = 0; k < N_TEXELS / 2; k++) {
-           GLint sum = 0;
-           for (i = 0; i < nn_comp; i++) {
-               sum += input[k][i];
-           }
-           if (minSum > sum) {
-               minSum = sum;
-               minColL = k;
-           }
-           if (maxSum < sum) {
-               maxSum = sum;
-               maxColL = k;
-           }
-           sumL += sum;
-       }
-       
-       nn_comp--;
-   }
-
-   nn_comp = n_comp;
-   while ((minColR == maxColR) && nn_comp) {
-       minSum = 2000; /* big enough */
-       maxSum = -1; /* small enough */
-       for (k = N_TEXELS / 2; k < N_TEXELS; k++) {
-           GLint sum = 0;
-           for (i = 0; i < nn_comp; i++) {
-               sum += input[k][i];
-           }
-           if (minSum > sum) {
-               minSum = sum;
-               minColR = k;
-           }
-           if (maxSum < sum) {
-               maxSum = sum;
-               maxColR = k;
-           }
-           sumR += sum;
-       }
-
-       nn_comp--;
-   }
-
-   /* choose the common vector (yuck!) */
-   {
-      GLint j1, j2;
-      GLint v1 = 0, v2 = 0;
-      GLfloat err = 1e9; /* big enough */
-      GLfloat 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++) {
-            GLfloat e = 0.0F;
-            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 */
-      MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);
-
-      /* add in texels */
-      lolo = 0;
-      for (k = N_TEXELS / 2 - 1; k >= 0; k--) {
-         GLint texel;
-         /* interpolate color */
-         CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
-         /* add in texel */
-         lolo <<= 2;
-         lolo |= texel;
-      }
-      
-      cc[0] = lolo;
-   }
-
-   /* right microtile */
-   cc[1] = 0;
-   if (minColR != maxColR) {
-      /* compute interpolation vector */
-      MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[1]);
-
-      /* add in texels */
-      lohi = 0;
-      for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
-         GLint texel;
-         /* interpolate color */
-         CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
-         /* 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, (GLuint)(vec[j][ACOMP] / 8.0F));
-   }
-   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, (GLuint)(vec[j][i] / 8.0F));
-      }
-   }
-   ((Fx64 *)cc)[1] = hi;
-}
-
-
-static void
-fxt1_quantize_HI (GLuint *cc,
-                  GLubyte input[N_TEXELS][MAX_COMP],
-                  GLubyte reord[N_TEXELS][MAX_COMP], GLint n)
-{
-   const GLint n_vect = 6; /* highest vector number */
-   const GLint n_comp = 3; /* 3 components: R, G, B */
-   GLfloat b = 0.0F;       /* phoudoin: silent compiler! */
-   GLfloat iv[MAX_COMP];   /* interpolation vector */
-   GLint i, k;
-   GLuint hihi; /* high quadword: hi dword */
-
-   GLint minSum = 2000; /* big enough */
-   GLint maxSum = -1; /* small enough */
-   GLint minCol = 0; /* phoudoin: silent compiler! */
-   GLint 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++) {
-      GLint 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) {
-      MAKEIVEC(n_vect, n_comp, iv, b, reord[minCol], reord[maxCol]);
-   }
-
-   /* add in texels */
-   for (k = N_TEXELS - 1; k >= 0; k--) {
-      GLint t = k * 3;
-      GLuint *kk = (GLuint *)((char *)cc + t / 8);
-      GLint texel = n_vect + 1; /* transparent black */
-
-      if (!ISTBLACK(input[k])) {
-         if (minCol != maxCol) {
-            /* interpolate color */
-            CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
-            /* add in texel */
-            kk[0] |= texel << (t & 7);
-         }
-      } else {
-         /* add in texel */
-         kk[0] |= texel << (t & 7);
-      }
-   }
-}
-
-
-static void
-fxt1_quantize_MIXED1 (GLuint *cc,
-                      GLubyte input[N_TEXELS][MAX_COMP])
-{
-   const GLint n_vect = 2; /* highest vector number in each microtile */
-   const GLint n_comp = 3; /* 3 components: R, G, B */
-   GLubyte vec[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */
-   GLfloat b, iv[MAX_COMP]; /* interpolation vector */
-   GLint i, j, k;
-   Fx64 hi; /* high quadword */
-   GLuint lohi, lolo; /* low quadword: hi dword, lo dword */
-
-   GLint minSum;
-   GLint maxSum;
-   GLint minColL = 0, maxColL = -1;
-   GLint 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 = 2000; /* big enough */
-   maxSum = -1; /* small enough */
-   for (k = 0; k < N_TEXELS / 2; k++) {
-      if (!ISTBLACK(input[k])) {
-         GLint 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 = 2000; /* big enough */
-   maxSum = -1; /* small enough */
-   for (; k < N_TEXELS; k++) {
-      if (!ISTBLACK(input[k])) {
-         GLint 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] = ~0u;
-      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 */
-         MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);
-
-         /* add in texels */
-         lolo = 0;
-         for (k = N_TEXELS / 2 - 1; k >= 0; k--) {
-            GLint texel = n_vect + 1; /* transparent black */
-            if (!ISTBLACK(input[k])) {
-               /* interpolate color */
-               CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
-            }
-            /* add in texel */
-            lolo <<= 2;
-            lolo |= texel;
-         }
-         cc[0] = lolo;
-      }
-   }
-
-   /* right microtile */
-   if (maxColR == -1) {
-      /* all transparent black */
-      cc[1] = ~0u;
-      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 */
-         MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[3]);
-
-         /* add in texels */
-         lohi = 0;
-         for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
-            GLint texel = n_vect + 1; /* transparent black */
-            if (!ISTBLACK(input[k])) {
-               /* interpolate color */
-               CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
-            }
-            /* 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 (GLuint *cc,
-                      GLubyte input[N_TEXELS][MAX_COMP])
-{
-   const GLint n_vect = 3; /* highest vector number in each microtile */
-   const GLint n_comp = 3; /* 3 components: R, G, B */
-   GLubyte vec[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */
-   GLfloat b, iv[MAX_COMP]; /* interpolation vector */
-   GLint i, j, k;
-   Fx64 hi; /* high quadword */
-   GLuint lohi, lolo; /* low quadword: hi dword, lo dword */
-
-   GLint minColL = 0, maxColL = 0;
-   GLint minColR = 0, maxColR = 0;
-#if 0
-   GLint minSum;
-   GLint 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 = 2000; /* big enough */
-   maxSum = -1; /* small enough */
-   for (k = 0; k < N_TEXELS / 2; k++) {
-      GLint 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 = 2000; /* big enough */
-   maxSum = -1; /* small enough */
-   for (; k < N_TEXELS; k++) {
-      GLint 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
-   GLint minVal;
-   GLint maxVal;
-   GLint maxVarL = fxt1_variance(NULL, input, n_comp, N_TEXELS / 2);
-   GLint 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 = 2000; /* big enough */
-   maxVal = -1; /* small enough */
-   for (k = 0; k < N_TEXELS / 2; k++) {
-      GLint t = input[k][maxVarL];
-      if (minVal > t) {
-         minVal = t;
-         minColL = k;
-      }
-      if (maxVal < t) {
-         maxVal = t;
-         maxColL = k;
-      }
-   }
-   minVal = 2000; /* big enough */
-   maxVal = -1; /* small enough */
-   for (; k < N_TEXELS; k++) {
-      GLint 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 */
-      MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);
-
-      /* add in texels */
-      lolo = 0;
-      for (k = N_TEXELS / 2 - 1; k >= 0; k--) {
-         GLint texel;
-         /* interpolate color */
-         CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
-         /* add in texel */
-         lolo <<= 2;
-         lolo |= texel;
-      }
-
-      /* funky encoding for LSB of green */
-      if ((GLint)((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 */
-      MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[3]);
-
-      /* add in texels */
-      lohi = 0;
-      for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {
-         GLint texel;
-         /* interpolate color */
-         CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);
-         /* add in texel */
-         lohi <<= 2;
-         lohi |= texel;
-      }
-
-      /* funky encoding for LSB of green */
-      if ((GLint)((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 (GLuint *cc, const GLubyte *lines[], GLint comps)
-{
-   GLint trualpha;
-   GLubyte reord[N_TEXELS][MAX_COMP];
-
-   GLubyte input[N_TEXELS][MAX_COMP];
-   GLint i, k, l;
-
-   if (comps == 3) {
-      /* make the whole block opaque */
-      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] = ~0u;
-      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
-}
-
-
-static void
-fxt1_encode (GLuint width, GLuint height, GLint comps,
-             const void *source, GLint srcRowStride,
-             void *dest, GLint destRowStride)
-{
-   GLuint x, y;
-   const GLubyte *data;
-   GLuint *encoded = (GLuint *)dest;
-   void *newSource = NULL;
-
-   assert(comps == 3 || comps == 4);
-
-   /* Replicate image if width is not M8 or height is not M4 */
-   if ((width & 7) | (height & 3)) {
-      GLint newWidth = (width + 7) & ~7;
-      GLint newHeight = (height + 3) & ~3;
-      newSource = malloc(comps * newWidth * newHeight * sizeof(GLchan));
-      if (!newSource) {
-         GET_CURRENT_CONTEXT(ctx);
-         _mesa_error(ctx, GL_OUT_OF_MEMORY, "texture compression");
-         goto cleanUp;
-      }
-      _mesa_upscale_teximage2d(width, height, newWidth, newHeight,
-                               comps, (const GLchan *) source,
-                               srcRowStride, (GLchan *) newSource);
-      source = newSource;
-      width = newWidth;
-      height = newHeight;
-      srcRowStride = comps * newWidth;
-   }
-
-   /* convert from 16/32-bit channels to GLubyte if needed */
-   if (CHAN_TYPE != GL_UNSIGNED_BYTE) {
-      const GLuint n = width * height * comps;
-      const GLchan *src = (const GLchan *) source;
-      GLubyte *dest = (GLubyte *) malloc(n * sizeof(GLubyte));
-      GLuint i;
-      if (!dest) {
-         GET_CURRENT_CONTEXT(ctx);
-         _mesa_error(ctx, GL_OUT_OF_MEMORY, "texture compression");
-         goto cleanUp;
-      }
-      for (i = 0; i < n; i++) {
-         dest[i] = CHAN_TO_UBYTE(src[i]);
-      }
-      if (newSource != NULL) {
-         free(newSource);
-      }
-      newSource = dest;  /* we'll free this buffer before returning */
-      source = dest;  /* the new, GLubyte incoming image */
-   }
-
-   data = (const GLubyte *) source;
-   destRowStride = (destRowStride - width * 2) / 4;
-   for (y = 0; y < height; y += 4) {
-      GLuint offs = 0 + (y + 0) * srcRowStride;
-      for (x = 0; x < width; x += 8) {
-         const GLubyte *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 */
-         encoded += 4;
-      }
-      encoded += destRowStride;
-   }
-
- cleanUp:
-   if (newSource != NULL) {
-      free(newSource);
-   }
-}
-
-
-/***************************************************************************\
- * 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 const GLubyte _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 GLubyte _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) (((GLuint *)(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)
-
-
-static void
-fxt1_decode_1HI (const GLubyte *code, GLint t, GLchan *rgba)
-{
-   const GLuint *cc;
-
-   t *= 3;
-   cc = (const GLuint *)(code + t / 8);
-   t = (cc[0] >> (t & 7)) & 7;
-
-   if (t == 7) {
-      rgba[RCOMP] = rgba[GCOMP] = rgba[BCOMP] = rgba[ACOMP] = 0;
-   } else {
-      GLubyte r, g, b;
-      cc = (const GLuint *)(code + 12);
-      if (t == 0) {
-         b = UP5(CC_SEL(cc, 0));
-         g = UP5(CC_SEL(cc, 5));
-         r = UP5(CC_SEL(cc, 10));
-      } else if (t == 6) {
-         b = UP5(CC_SEL(cc, 15));
-         g = UP5(CC_SEL(cc, 20));
-         r = UP5(CC_SEL(cc, 25));
-      } else {
-         b = LERP(6, t, UP5(CC_SEL(cc, 0)), UP5(CC_SEL(cc, 15)));
-         g = LERP(6, t, UP5(CC_SEL(cc, 5)), UP5(CC_SEL(cc, 20)));
-         r = LERP(6, t, UP5(CC_SEL(cc, 10)), UP5(CC_SEL(cc, 25)));
-      }
-      rgba[RCOMP] = UBYTE_TO_CHAN(r);
-      rgba[GCOMP] = UBYTE_TO_CHAN(g);
-      rgba[BCOMP] = UBYTE_TO_CHAN(b);
-      rgba[ACOMP] = CHAN_MAX;
-   }
-}
-
-
-static void
-fxt1_decode_1CHROMA (const GLubyte *code, GLint t, GLchan *rgba)
-{
-   const GLuint *cc;
-   GLuint kk;
-
-   cc = (const GLuint *)code;
-   if (t & 16) {
-      cc++;
-      t &= 15;
-   }
-   t = (cc[0] >> (t * 2)) & 3;
-
-   t *= 15;
-   cc = (const GLuint *)(code + 8 + t / 8);
-   kk = cc[0] >> (t & 7);
-   rgba[BCOMP] = UBYTE_TO_CHAN( UP5(kk) );
-   rgba[GCOMP] = UBYTE_TO_CHAN( UP5(kk >> 5) );
-   rgba[RCOMP] = UBYTE_TO_CHAN( UP5(kk >> 10) );
-   rgba[ACOMP] = CHAN_MAX;
-}
-
-
-static void
-fxt1_decode_1MIXED (const GLubyte *code, GLint t, GLchan *rgba)
-{
-   const GLuint *cc;
-   GLuint col[2][3];
-   GLint glsb, selb;
-
-   cc = (const GLuint *)code;
-   if (t & 16) {
-      t &= 15;
-      t = (cc[1] >> (t * 2)) & 3;
-      /* col 2 */
-      col[0][BCOMP] = (*(const GLuint *)(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 */
-         rgba[RCOMP] = rgba[BCOMP] = rgba[GCOMP] = rgba[ACOMP] = 0;
-      } else {
-         GLubyte r, g, b;
-         if (t == 0) {
-            b = UP5(col[0][BCOMP]);
-            g = UP5(col[0][GCOMP]);
-            r = UP5(col[0][RCOMP]);
-         } else if (t == 2) {
-            b = UP5(col[1][BCOMP]);
-            g = UP6(col[1][GCOMP], glsb);
-            r = UP5(col[1][RCOMP]);
-         } else {
-            b = (UP5(col[0][BCOMP]) + UP5(col[1][BCOMP])) / 2;
-            g = (UP5(col[0][GCOMP]) + UP6(col[1][GCOMP], glsb)) / 2;
-            r = (UP5(col[0][RCOMP]) + UP5(col[1][RCOMP])) / 2;
-         }
-         rgba[RCOMP] = UBYTE_TO_CHAN(r);
-         rgba[GCOMP] = UBYTE_TO_CHAN(g);
-         rgba[BCOMP] = UBYTE_TO_CHAN(b);
-         rgba[ACOMP] = CHAN_MAX;
-      }
-   } else {
-      /* alpha[0] == 0 */
-      GLubyte r, g, b;
-      if (t == 0) {
-         b = UP5(col[0][BCOMP]);
-         g = UP6(col[0][GCOMP], glsb ^ selb);
-         r = UP5(col[0][RCOMP]);
-      } else if (t == 3) {
-         b = UP5(col[1][BCOMP]);
-         g = UP6(col[1][GCOMP], glsb);
-         r = UP5(col[1][RCOMP]);
-      } else {
-         b = LERP(3, t, UP5(col[0][BCOMP]), UP5(col[1][BCOMP]));
-         g = LERP(3, t, UP6(col[0][GCOMP], glsb ^ selb),
-                        UP6(col[1][GCOMP], glsb));
-         r = LERP(3, t, UP5(col[0][RCOMP]), UP5(col[1][RCOMP]));
-      }
-      rgba[RCOMP] = UBYTE_TO_CHAN(r);
-      rgba[GCOMP] = UBYTE_TO_CHAN(g);
-      rgba[BCOMP] = UBYTE_TO_CHAN(b);
-      rgba[ACOMP] = CHAN_MAX;
-   }
-}
-
-
-static void
-fxt1_decode_1ALPHA (const GLubyte *code, GLint t, GLchan *rgba)
-{
-   const GLuint *cc;
-   GLubyte r, g, b, a;
-
-   cc = (const GLuint *)code;
-   if (CC_SEL(cc, 124) & 1) {
-      /* lerp == 1 */
-      GLuint col0[4];
-
-      if (t & 16) {
-         t &= 15;
-         t = (cc[1] >> (t * 2)) & 3;
-         /* col 2 */
-         col0[BCOMP] = (*(const GLuint *)(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) {
-         b = UP5(col0[BCOMP]);
-         g = UP5(col0[GCOMP]);
-         r = UP5(col0[RCOMP]);
-         a = UP5(col0[ACOMP]);
-      } else if (t == 3) {
-         b = UP5(CC_SEL(cc, 79));
-         g = UP5(CC_SEL(cc, 84));
-         r = UP5(CC_SEL(cc, 89));
-         a = UP5(CC_SEL(cc, 114));
-      } else {
-         b = LERP(3, t, UP5(col0[BCOMP]), UP5(CC_SEL(cc, 79)));
-         g = LERP(3, t, UP5(col0[GCOMP]), UP5(CC_SEL(cc, 84)));
-         r = LERP(3, t, UP5(col0[RCOMP]), UP5(CC_SEL(cc, 89)));
-         a = 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 */
-         r = g = b = a = 0;
-      } else {
-         GLuint kk;
-         cc = (const GLuint *)code;
-         a = UP5(cc[3] >> (t * 5 + 13));
-         t *= 15;
-         cc = (const GLuint *)(code + 8 + t / 8);
-         kk = cc[0] >> (t & 7);
-         b = UP5(kk);
-         g = UP5(kk >> 5);
-         r = UP5(kk >> 10);
-      }
-   }
-   rgba[RCOMP] = UBYTE_TO_CHAN(r);
-   rgba[GCOMP] = UBYTE_TO_CHAN(g);
-   rgba[BCOMP] = UBYTE_TO_CHAN(b);
-   rgba[ACOMP] = UBYTE_TO_CHAN(a);
-}
-
-
-void
-fxt1_decode_1 (const void *texture, GLint stride, /* in pixels */
-               GLint i, GLint j, GLchan *rgba)
-{
-   static void (*decode_1[]) (const GLubyte *, GLint, GLchan *) = {
-      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??" */
-   };
-
-   const GLubyte *code = (const GLubyte *)texture +
-                         ((j / 4) * (stride / 8) + (i / 8)) * 16;
-   GLint mode = CC_SEL(code, 125);
-   GLint t = i & 7;
-
-   if (t & 4) {
-      t += 12;
-   }
-   t += (j & 3) * 4;
-
-   decode_1[mode](code, t, rgba);
-}
-
-
-#endif /* FEATURE_texture_fxt1 */
+/*

+ * Mesa 3-D graphics library

+ * Version:  7.1

+ *

+ * Copyright (C) 1999-2008  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_3DFX_texture_compression_FXT1 support.

+ */

+

+

+#include "glheader.h"

+#include "imports.h"

+#include "colormac.h"

+#include "image.h"

+#include "macros.h"

+#include "mipmap.h"

+#include "texcompress.h"

+#include "texcompress_fxt1.h"

+#include "texstore.h"

+

+

+#if FEATURE_texture_fxt1

+

+

+static void

+fxt1_encode (GLuint width, GLuint height, GLint comps,

+             const void *source, GLint srcRowStride,

+             void *dest, GLint destRowStride);

+

+void

+fxt1_decode_1 (const void *texture, GLint stride,

+               GLint i, GLint j, GLchan *rgba);

+

+

+/**

+ * Store user's image in rgb_fxt1 format.

+ */

+GLboolean

+_mesa_texstore_rgb_fxt1(TEXSTORE_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_FORMAT_RGB_FXT1);

+   ASSERT(dstXoffset % 8 == 0);

+   ASSERT(dstYoffset % 4 == 0);

+   ASSERT(dstZoffset     == 0);

+   (void) dstZoffset;

+   (void) dstImageOffsets;

+

+   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,

+                                             _mesa_get_format_base_format(dstFormat),

+                                             srcWidth, srcHeight, srcDepth,

+                                             srcFormat, srcType, srcAddr,

+                                             srcPacking);

+      if (!tempImage)

+         return GL_FALSE; /* out of memory */

+      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,

+                                        dstFormat,

+                                        texWidth, (GLubyte *) dstAddr);

+

+   fxt1_encode(srcWidth, srcHeight, 3, pixels, srcRowStride,

+               dst, dstRowStride);

+

+   if (tempImage)

+      free((void*) tempImage);

+

+   return GL_TRUE;

+}

+

+

+/**

+ * Store user's image in rgba_fxt1 format.

+ */

+GLboolean

+_mesa_texstore_rgba_fxt1(TEXSTORE_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_FORMAT_RGBA_FXT1);

+   ASSERT(dstXoffset % 8 == 0);

+   ASSERT(dstYoffset % 4 == 0);

+   ASSERT(dstZoffset     == 0);

+   (void) dstZoffset;

+   (void) dstImageOffsets;

+

+   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,

+                                             _mesa_get_format_base_format(dstFormat),

+                                             srcWidth, srcHeight, srcDepth,

+                                             srcFormat, srcType, srcAddr,

+                                             srcPacking);

+      if (!tempImage)

+         return GL_FALSE; /* out of memory */

+      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,

+                                        dstFormat,

+                                        texWidth, (GLubyte *) dstAddr);

+

+   fxt1_encode(srcWidth, srcHeight, 4, pixels, srcRowStride,

+               dst, dstRowStride);

+

+   if (tempImage)

+      free((void*) tempImage);

+

+   return GL_TRUE;

+}

+

+

+void

+_mesa_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->RowStride, 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]);

+}

+

+

+void

+_mesa_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->RowStride, 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] = 1.0F;

+}

+

+

+

+/***************************************************************************\

+ * 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 highly UNoptimized;

+ * moreover, it is sub-optimal due to initial conditions passed

+ * to Lloyd's algorithm (the interpolation modes are even 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) (*((GLuint *)(v)) == 0)

+

+

+/*

+ * Define a 64-bit unsigned integer type and macros

+ */

+#if 1

+

+#define FX64_NATIVE 1

+

+typedef uint64_t Fx64;

+

+#define FX64_MOV32(a, b) a = b

+#define FX64_OR32(a, b)  a |= b

+#define FX64_SHL(a, c)   a <<= c

+

+#else

+

+#define FX64_NATIVE 0

+

+typedef struct {

+   GLuint 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

+

+

+#define F(i) (GLfloat)1 /* can be used to obtain an oblong metric: 0.30 / 0.59 / 0.11 */

+#define SAFECDOT 1 /* for paranoids */

+

+#define MAKEIVEC(NV, NC, IV, B, V0, V1)  \

+   do {                                  \

+      /* compute interpolation vector */ \

+      GLfloat d2 = 0.0F;                 \

+      GLfloat rd2;                       \

+                                         \

+      for (i = 0; i < NC; i++) {         \

+         IV[i] = (V1[i] - V0[i]) * F(i); \

+         d2 += IV[i] * IV[i];            \

+      }                                  \

+      rd2 = (GLfloat)NV / d2;            \

+      B = 0;                             \

+      for (i = 0; i < NC; i++) {         \

+         IV[i] *= F(i);                  \

+         B -= IV[i] * V0[i];             \

+         IV[i] *= rd2;                   \

+      }                                  \

+      B = B * rd2 + 0.5f;                \

+   } while (0)

+

+#define CALCCDOT(TEXEL, NV, NC, IV, B, V)\

+   do {                                  \

+      GLfloat dot = 0.0F;                \

+      for (i = 0; i < NC; i++) {         \

+         dot += V[i] * IV[i];            \

+      }                                  \

+      TEXEL = (GLint)(dot + B);          \

+      if (SAFECDOT) {                    \

+         if (TEXEL < 0) {                \

+            TEXEL = 0;                   \

+         } else if (TEXEL > NV) {        \

+            TEXEL = NV;                  \

+         }                               \

+      }                                  \

+   } while (0)

+

+

+static GLint

+fxt1_bestcol (GLfloat vec[][MAX_COMP], GLint nv,

+              GLubyte input[MAX_COMP], GLint nc)

+{

+   GLint i, j, best = -1;

+   GLfloat err = 1e9; /* big enough */

+

+   for (j = 0; j < nv; j++) {

+      GLfloat e = 0.0F;

+      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 GLint

+fxt1_worst (GLfloat vec[MAX_COMP],

+            GLubyte input[N_TEXELS][MAX_COMP], GLint nc, GLint n)

+{

+   GLint i, k, worst = -1;

+   GLfloat err = -1.0F; /* small enough */

+

+   for (k = 0; k < n; k++) {

+      GLfloat e = 0.0F;

+      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 GLint

+fxt1_variance (GLdouble variance[MAX_COMP],

+               GLubyte input[N_TEXELS][MAX_COMP], GLint nc, GLint n)

+{

+   GLint i, k, best = 0;

+   GLint sx, sx2;

+   GLdouble var, maxvar = -1; /* small enough */

+   GLdouble teenth = 1.0 / n;

+

+   for (i = 0; i < nc; i++) {

+      sx = sx2 = 0;

+      for (k = 0; k < n; k++) {

+         GLint 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 GLint

+fxt1_choose (GLfloat vec[][MAX_COMP], GLint nv,

+             GLubyte input[N_TEXELS][MAX_COMP], GLint nc, GLint n)

+{

+#if 0

+   /* Choose colors from a grid.

+    */

+   GLint i, j;

+

+   for (j = 0; j < nv; j++) {

+      GLint 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).

+    */

+   GLint i, j, k;

+   GLint minSum = 2000; /* big enough */

+   GLint maxSum = -1; /* small enough */

+   GLint minCol = 0; /* phoudoin: silent compiler! */

+   GLint maxCol = 0; /* phoudoin: silent compiler! */

+

+   struct {

+      GLint flag;

+      GLint key;

+      GLint freq;

+      GLint idx;

+   } hist[N_TEXELS];

+   GLint lenh = 0;

+

+   memset(hist, 0, sizeof(hist));

+

+   for (k = 0; k < n; k++) {

+      GLint l;

+      GLint key = 0;

+      GLint 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] = (GLfloat)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) / (GLfloat)(nv - 1);

+      }

+   }

+#endif

+

+   return !0;

+}

+

+

+static GLint

+fxt1_lloyd (GLfloat vec[][MAX_COMP], GLint nv,

+            GLubyte input[N_TEXELS][MAX_COMP], GLint nc, GLint 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 its 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

+    */

+

+   GLint sum[MAX_VECT][MAX_COMP]; /* used to accumulate closest texels */

+   GLint cnt[MAX_VECT]; /* how many times a certain vector was chosen */

+   GLfloat error, lasterror = 1e9;

+

+   GLint 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

+         GLint best = -1;

+         GLfloat err = 1e9; /* big enough */

+         /* determine best vector */

+         for (j = 0; j < nv; j++) {

+            GLfloat 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

+         GLint best = fxt1_bestcol(vec, nv, input[k], nc, &err);

+#endif

+         assert(best >= 0);

+         /* 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]) {

+            GLfloat div = 1.0F / 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 */

+            GLint 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 (GLuint *cc,

+                      GLubyte input[N_TEXELS][MAX_COMP])

+{

+   const GLint n_vect = 4; /* 4 base vectors to find */

+   const GLint n_comp = 3; /* 3 components: R, G, B */

+   GLfloat vec[MAX_VECT][MAX_COMP];

+   GLint i, j, k;

+   Fx64 hi; /* high quadword */

+   GLuint 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, (GLuint)(vec[j][i] / 8.0F));

+      }

+   }

+   ((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 (GLuint *cc,

+                      GLubyte input[N_TEXELS][MAX_COMP],

+                      GLubyte reord[N_TEXELS][MAX_COMP], GLint n)

+{

+   const GLint n_vect = 3; /* 3 base vectors to find */

+   const GLint n_comp = 4; /* 4 components: R, G, B, A */

+   GLfloat vec[MAX_VECT][MAX_COMP];

+   GLint i, j, k;

+   Fx64 hi; /* high quadword */

+   GLuint 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, (GLuint)(vec[j][ACOMP] / 8.0F));

+   }

+   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, (GLuint)(vec[j][i] / 8.0F));

+      }

+   }

+   ((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 (GLuint *cc,

+                      GLubyte input[N_TEXELS][MAX_COMP])

+{

+   const GLint n_vect = 3; /* highest vector number in each microtile */

+   const GLint n_comp = 4; /* 4 components: R, G, B, A */

+   GLfloat vec[1 + 1 + 1][MAX_COMP]; /* 1.5 extrema for each sub-block */

+   GLfloat b, iv[MAX_COMP]; /* interpolation vector */

+   GLint i, j, k;

+   Fx64 hi; /* high quadword */

+   GLuint lohi, lolo; /* low quadword: hi dword, lo dword */

+

+   GLint minSum;

+   GLint maxSum;

+   GLint minColL = 0, maxColL = 0;

+   GLint minColR = 0, maxColR = 0;

+   GLint sumL = 0, sumR = 0;

+   GLint nn_comp;

+   /* 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).

+    */

+   nn_comp = n_comp;

+   while ((minColL == maxColL) && nn_comp) {

+       minSum = 2000; /* big enough */

+       maxSum = -1; /* small enough */

+       for (k = 0; k < N_TEXELS / 2; k++) {

+           GLint sum = 0;

+           for (i = 0; i < nn_comp; i++) {

+               sum += input[k][i];

+           }

+           if (minSum > sum) {

+               minSum = sum;

+               minColL = k;

+           }

+           if (maxSum < sum) {

+               maxSum = sum;

+               maxColL = k;

+           }

+           sumL += sum;

+       }

+       

+       nn_comp--;

+   }

+

+   nn_comp = n_comp;

+   while ((minColR == maxColR) && nn_comp) {

+       minSum = 2000; /* big enough */

+       maxSum = -1; /* small enough */

+       for (k = N_TEXELS / 2; k < N_TEXELS; k++) {

+           GLint sum = 0;

+           for (i = 0; i < nn_comp; i++) {

+               sum += input[k][i];

+           }

+           if (minSum > sum) {

+               minSum = sum;

+               minColR = k;

+           }

+           if (maxSum < sum) {

+               maxSum = sum;

+               maxColR = k;

+           }

+           sumR += sum;

+       }

+

+       nn_comp--;

+   }

+

+   /* choose the common vector (yuck!) */

+   {

+      GLint j1, j2;

+      GLint v1 = 0, v2 = 0;

+      GLfloat err = 1e9; /* big enough */

+      GLfloat 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++) {

+            GLfloat e = 0.0F;

+            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 */

+      MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);

+

+      /* add in texels */

+      lolo = 0;

+      for (k = N_TEXELS / 2 - 1; k >= 0; k--) {

+         GLint texel;

+         /* interpolate color */

+         CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);

+         /* add in texel */

+         lolo <<= 2;

+         lolo |= texel;

+      }

+      

+      cc[0] = lolo;

+   }

+

+   /* right microtile */

+   cc[1] = 0;

+   if (minColR != maxColR) {

+      /* compute interpolation vector */

+      MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[1]);

+

+      /* add in texels */

+      lohi = 0;

+      for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {

+         GLint texel;

+         /* interpolate color */

+         CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);

+         /* 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, (GLuint)(vec[j][ACOMP] / 8.0F));

+   }

+   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, (GLuint)(vec[j][i] / 8.0F));

+      }

+   }

+   ((Fx64 *)cc)[1] = hi;

+}

+

+

+static void

+fxt1_quantize_HI (GLuint *cc,

+                  GLubyte input[N_TEXELS][MAX_COMP],

+                  GLubyte reord[N_TEXELS][MAX_COMP], GLint n)

+{

+   const GLint n_vect = 6; /* highest vector number */

+   const GLint n_comp = 3; /* 3 components: R, G, B */

+   GLfloat b = 0.0F;       /* phoudoin: silent compiler! */

+   GLfloat iv[MAX_COMP];   /* interpolation vector */

+   GLint i, k;

+   GLuint hihi; /* high quadword: hi dword */

+

+   GLint minSum = 2000; /* big enough */

+   GLint maxSum = -1; /* small enough */

+   GLint minCol = 0; /* phoudoin: silent compiler! */

+   GLint 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++) {

+      GLint 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) {

+      MAKEIVEC(n_vect, n_comp, iv, b, reord[minCol], reord[maxCol]);

+   }

+

+   /* add in texels */

+   for (k = N_TEXELS - 1; k >= 0; k--) {

+      GLint t = k * 3;

+      GLuint *kk = (GLuint *)((char *)cc + t / 8);

+      GLint texel = n_vect + 1; /* transparent black */

+

+      if (!ISTBLACK(input[k])) {

+         if (minCol != maxCol) {

+            /* interpolate color */

+            CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);

+            /* add in texel */

+            kk[0] |= texel << (t & 7);

+         }

+      } else {

+         /* add in texel */

+         kk[0] |= texel << (t & 7);

+      }

+   }

+}

+

+

+static void

+fxt1_quantize_MIXED1 (GLuint *cc,

+                      GLubyte input[N_TEXELS][MAX_COMP])

+{

+   const GLint n_vect = 2; /* highest vector number in each microtile */

+   const GLint n_comp = 3; /* 3 components: R, G, B */

+   GLubyte vec[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */

+   GLfloat b, iv[MAX_COMP]; /* interpolation vector */

+   GLint i, j, k;

+   Fx64 hi; /* high quadword */

+   GLuint lohi, lolo; /* low quadword: hi dword, lo dword */

+

+   GLint minSum;

+   GLint maxSum;

+   GLint minColL = 0, maxColL = -1;

+   GLint 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 = 2000; /* big enough */

+   maxSum = -1; /* small enough */

+   for (k = 0; k < N_TEXELS / 2; k++) {

+      if (!ISTBLACK(input[k])) {

+         GLint 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 = 2000; /* big enough */

+   maxSum = -1; /* small enough */

+   for (; k < N_TEXELS; k++) {

+      if (!ISTBLACK(input[k])) {

+         GLint 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] = ~0u;

+      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 */

+         MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);

+

+         /* add in texels */

+         lolo = 0;

+         for (k = N_TEXELS / 2 - 1; k >= 0; k--) {

+            GLint texel = n_vect + 1; /* transparent black */

+            if (!ISTBLACK(input[k])) {

+               /* interpolate color */

+               CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);

+            }

+            /* add in texel */

+            lolo <<= 2;

+            lolo |= texel;

+         }

+         cc[0] = lolo;

+      }

+   }

+

+   /* right microtile */

+   if (maxColR == -1) {

+      /* all transparent black */

+      cc[1] = ~0u;

+      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 */

+         MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[3]);

+

+         /* add in texels */

+         lohi = 0;

+         for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {

+            GLint texel = n_vect + 1; /* transparent black */

+            if (!ISTBLACK(input[k])) {

+               /* interpolate color */

+               CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);

+            }

+            /* 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 (GLuint *cc,

+                      GLubyte input[N_TEXELS][MAX_COMP])

+{

+   const GLint n_vect = 3; /* highest vector number in each microtile */

+   const GLint n_comp = 3; /* 3 components: R, G, B */

+   GLubyte vec[2 * 2][MAX_COMP]; /* 2 extrema for each sub-block */

+   GLfloat b, iv[MAX_COMP]; /* interpolation vector */

+   GLint i, j, k;

+   Fx64 hi; /* high quadword */

+   GLuint lohi, lolo; /* low quadword: hi dword, lo dword */

+

+   GLint minColL = 0, maxColL = 0;

+   GLint minColR = 0, maxColR = 0;

+#if 0

+   GLint minSum;

+   GLint 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 = 2000; /* big enough */

+   maxSum = -1; /* small enough */

+   for (k = 0; k < N_TEXELS / 2; k++) {

+      GLint 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 = 2000; /* big enough */

+   maxSum = -1; /* small enough */

+   for (; k < N_TEXELS; k++) {

+      GLint 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

+   GLint minVal;

+   GLint maxVal;

+   GLint maxVarL = fxt1_variance(NULL, input, n_comp, N_TEXELS / 2);

+   GLint 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 = 2000; /* big enough */

+   maxVal = -1; /* small enough */

+   for (k = 0; k < N_TEXELS / 2; k++) {

+      GLint t = input[k][maxVarL];

+      if (minVal > t) {

+         minVal = t;

+         minColL = k;

+      }

+      if (maxVal < t) {

+         maxVal = t;

+         maxColL = k;

+      }

+   }

+   minVal = 2000; /* big enough */

+   maxVal = -1; /* small enough */

+   for (; k < N_TEXELS; k++) {

+      GLint 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 */

+      MAKEIVEC(n_vect, n_comp, iv, b, vec[0], vec[1]);

+

+      /* add in texels */

+      lolo = 0;

+      for (k = N_TEXELS / 2 - 1; k >= 0; k--) {

+         GLint texel;

+         /* interpolate color */

+         CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);

+         /* add in texel */

+         lolo <<= 2;

+         lolo |= texel;

+      }

+

+      /* funky encoding for LSB of green */

+      if ((GLint)((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 */

+      MAKEIVEC(n_vect, n_comp, iv, b, vec[2], vec[3]);

+

+      /* add in texels */

+      lohi = 0;

+      for (k = N_TEXELS - 1; k >= N_TEXELS / 2; k--) {

+         GLint texel;

+         /* interpolate color */

+         CALCCDOT(texel, n_vect, n_comp, iv, b, input[k]);

+         /* add in texel */

+         lohi <<= 2;

+         lohi |= texel;

+      }

+

+      /* funky encoding for LSB of green */

+      if ((GLint)((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 (GLuint *cc, const GLubyte *lines[], GLint comps)

+{

+   GLint trualpha;

+   GLubyte reord[N_TEXELS][MAX_COMP];

+

+   GLubyte input[N_TEXELS][MAX_COMP];

+   GLint i, k, l;

+

+   if (comps == 3) {

+      /* make the whole block opaque */

+      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] = ~0u;

+      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

+}

+

+

+static void

+fxt1_encode (GLuint width, GLuint height, GLint comps,

+             const void *source, GLint srcRowStride,

+             void *dest, GLint destRowStride)

+{

+   GLuint x, y;

+   const GLubyte *data;

+   GLuint *encoded = (GLuint *)dest;

+   void *newSource = NULL;

+

+   assert(comps == 3 || comps == 4);

+

+   /* Replicate image if width is not M8 or height is not M4 */

+   if ((width & 7) | (height & 3)) {

+      GLint newWidth = (width + 7) & ~7;

+      GLint newHeight = (height + 3) & ~3;

+      newSource = malloc(comps * newWidth * newHeight * sizeof(GLchan));

+      if (!newSource) {

+         GET_CURRENT_CONTEXT(ctx);

+         _mesa_error(ctx, GL_OUT_OF_MEMORY, "texture compression");

+         goto cleanUp;

+      }

+      _mesa_upscale_teximage2d(width, height, newWidth, newHeight,

+                               comps, (const GLchan *) source,

+                               srcRowStride, (GLchan *) newSource);

+      source = newSource;

+      width = newWidth;

+      height = newHeight;

+      srcRowStride = comps * newWidth;

+   }

+

+   /* convert from 16/32-bit channels to GLubyte if needed */

+   if (CHAN_TYPE != GL_UNSIGNED_BYTE) {

+      const GLuint n = width * height * comps;

+      const GLchan *src = (const GLchan *) source;

+      GLubyte *dest = (GLubyte *) malloc(n * sizeof(GLubyte));

+      GLuint i;

+      if (!dest) {

+         GET_CURRENT_CONTEXT(ctx);

+         _mesa_error(ctx, GL_OUT_OF_MEMORY, "texture compression");

+         goto cleanUp;

+      }

+      for (i = 0; i < n; i++) {

+         dest[i] = CHAN_TO_UBYTE(src[i]);

+      }

+      if (newSource != NULL) {

+         free(newSource);

+      }

+      newSource = dest;  /* we'll free this buffer before returning */

+      source = dest;  /* the new, GLubyte incoming image */

+   }

+

+   data = (const GLubyte *) source;

+   destRowStride = (destRowStride - width * 2) / 4;

+   for (y = 0; y < height; y += 4) {

+      GLuint offs = 0 + (y + 0) * srcRowStride;

+      for (x = 0; x < width; x += 8) {

+         const GLubyte *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 */

+         encoded += 4;

+      }

+      encoded += destRowStride;

+   }

+

+ cleanUp:

+   if (newSource != NULL) {

+      free(newSource);

+   }

+}

+

+

+/***************************************************************************\

+ * 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 const GLubyte _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 GLubyte _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) (((GLuint *)(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)

+

+

+static void

+fxt1_decode_1HI (const GLubyte *code, GLint t, GLchan *rgba)

+{

+   const GLuint *cc;

+

+   t *= 3;

+   cc = (const GLuint *)(code + t / 8);

+   t = (cc[0] >> (t & 7)) & 7;

+

+   if (t == 7) {

+      rgba[RCOMP] = rgba[GCOMP] = rgba[BCOMP] = rgba[ACOMP] = 0;

+   } else {

+      GLubyte r, g, b;

+      cc = (const GLuint *)(code + 12);

+      if (t == 0) {

+         b = UP5(CC_SEL(cc, 0));

+         g = UP5(CC_SEL(cc, 5));

+         r = UP5(CC_SEL(cc, 10));

+      } else if (t == 6) {

+         b = UP5(CC_SEL(cc, 15));

+         g = UP5(CC_SEL(cc, 20));

+         r = UP5(CC_SEL(cc, 25));

+      } else {

+         b = LERP(6, t, UP5(CC_SEL(cc, 0)), UP5(CC_SEL(cc, 15)));

+         g = LERP(6, t, UP5(CC_SEL(cc, 5)), UP5(CC_SEL(cc, 20)));

+         r = LERP(6, t, UP5(CC_SEL(cc, 10)), UP5(CC_SEL(cc, 25)));

+      }

+      rgba[RCOMP] = UBYTE_TO_CHAN(r);

+      rgba[GCOMP] = UBYTE_TO_CHAN(g);

+      rgba[BCOMP] = UBYTE_TO_CHAN(b);

+      rgba[ACOMP] = CHAN_MAX;

+   }

+}

+

+

+static void

+fxt1_decode_1CHROMA (const GLubyte *code, GLint t, GLchan *rgba)

+{

+   const GLuint *cc;

+   GLuint kk;

+

+   cc = (const GLuint *)code;

+   if (t & 16) {

+      cc++;

+      t &= 15;

+   }

+   t = (cc[0] >> (t * 2)) & 3;

+

+   t *= 15;

+   cc = (const GLuint *)(code + 8 + t / 8);

+   kk = cc[0] >> (t & 7);

+   rgba[BCOMP] = UBYTE_TO_CHAN( UP5(kk) );

+   rgba[GCOMP] = UBYTE_TO_CHAN( UP5(kk >> 5) );

+   rgba[RCOMP] = UBYTE_TO_CHAN( UP5(kk >> 10) );

+   rgba[ACOMP] = CHAN_MAX;

+}

+

+

+static void

+fxt1_decode_1MIXED (const GLubyte *code, GLint t, GLchan *rgba)

+{

+   const GLuint *cc;

+   GLuint col[2][3];

+   GLint glsb, selb;

+

+   cc = (const GLuint *)code;

+   if (t & 16) {

+      t &= 15;

+      t = (cc[1] >> (t * 2)) & 3;

+      /* col 2 */

+      col[0][BCOMP] = (*(const GLuint *)(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 */

+         rgba[RCOMP] = rgba[BCOMP] = rgba[GCOMP] = rgba[ACOMP] = 0;

+      } else {

+         GLubyte r, g, b;

+         if (t == 0) {

+            b = UP5(col[0][BCOMP]);

+            g = UP5(col[0][GCOMP]);

+            r = UP5(col[0][RCOMP]);

+         } else if (t == 2) {

+            b = UP5(col[1][BCOMP]);

+            g = UP6(col[1][GCOMP], glsb);

+            r = UP5(col[1][RCOMP]);

+         } else {

+            b = (UP5(col[0][BCOMP]) + UP5(col[1][BCOMP])) / 2;

+            g = (UP5(col[0][GCOMP]) + UP6(col[1][GCOMP], glsb)) / 2;

+            r = (UP5(col[0][RCOMP]) + UP5(col[1][RCOMP])) / 2;

+         }

+         rgba[RCOMP] = UBYTE_TO_CHAN(r);

+         rgba[GCOMP] = UBYTE_TO_CHAN(g);

+         rgba[BCOMP] = UBYTE_TO_CHAN(b);

+         rgba[ACOMP] = CHAN_MAX;

+      }

+   } else {

+      /* alpha[0] == 0 */

+      GLubyte r, g, b;

+      if (t == 0) {

+         b = UP5(col[0][BCOMP]);

+         g = UP6(col[0][GCOMP], glsb ^ selb);

+         r = UP5(col[0][RCOMP]);

+      } else if (t == 3) {

+         b = UP5(col[1][BCOMP]);

+         g = UP6(col[1][GCOMP], glsb);

+         r = UP5(col[1][RCOMP]);

+      } else {

+         b = LERP(3, t, UP5(col[0][BCOMP]), UP5(col[1][BCOMP]));

+         g = LERP(3, t, UP6(col[0][GCOMP], glsb ^ selb),

+                        UP6(col[1][GCOMP], glsb));

+         r = LERP(3, t, UP5(col[0][RCOMP]), UP5(col[1][RCOMP]));

+      }

+      rgba[RCOMP] = UBYTE_TO_CHAN(r);

+      rgba[GCOMP] = UBYTE_TO_CHAN(g);

+      rgba[BCOMP] = UBYTE_TO_CHAN(b);

+      rgba[ACOMP] = CHAN_MAX;

+   }

+}

+

+

+static void

+fxt1_decode_1ALPHA (const GLubyte *code, GLint t, GLchan *rgba)

+{

+   const GLuint *cc;

+   GLubyte r, g, b, a;

+

+   cc = (const GLuint *)code;

+   if (CC_SEL(cc, 124) & 1) {

+      /* lerp == 1 */

+      GLuint col0[4];

+

+      if (t & 16) {

+         t &= 15;

+         t = (cc[1] >> (t * 2)) & 3;

+         /* col 2 */

+         col0[BCOMP] = (*(const GLuint *)(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) {

+         b = UP5(col0[BCOMP]);

+         g = UP5(col0[GCOMP]);

+         r = UP5(col0[RCOMP]);

+         a = UP5(col0[ACOMP]);

+      } else if (t == 3) {

+         b = UP5(CC_SEL(cc, 79));

+         g = UP5(CC_SEL(cc, 84));

+         r = UP5(CC_SEL(cc, 89));

+         a = UP5(CC_SEL(cc, 114));

+      } else {

+         b = LERP(3, t, UP5(col0[BCOMP]), UP5(CC_SEL(cc, 79)));

+         g = LERP(3, t, UP5(col0[GCOMP]), UP5(CC_SEL(cc, 84)));

+         r = LERP(3, t, UP5(col0[RCOMP]), UP5(CC_SEL(cc, 89)));

+         a = 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 */

+         r = g = b = a = 0;

+      } else {

+         GLuint kk;

+         cc = (const GLuint *)code;

+         a = UP5(cc[3] >> (t * 5 + 13));

+         t *= 15;

+         cc = (const GLuint *)(code + 8 + t / 8);

+         kk = cc[0] >> (t & 7);

+         b = UP5(kk);

+         g = UP5(kk >> 5);

+         r = UP5(kk >> 10);

+      }

+   }

+   rgba[RCOMP] = UBYTE_TO_CHAN(r);

+   rgba[GCOMP] = UBYTE_TO_CHAN(g);

+   rgba[BCOMP] = UBYTE_TO_CHAN(b);

+   rgba[ACOMP] = UBYTE_TO_CHAN(a);

+}

+

+

+void

+fxt1_decode_1 (const void *texture, GLint stride, /* in pixels */

+               GLint i, GLint j, GLchan *rgba)

+{

+   static void (*decode_1[]) (const GLubyte *, GLint, GLchan *) = {

+      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??" */

+   };

+

+   const GLubyte *code = (const GLubyte *)texture +

+                         ((j / 4) * (stride / 8) + (i / 8)) * 16;

+   GLint mode = CC_SEL(code, 125);

+   GLint t = i & 7;

+

+   if (t & 4) {

+      t += 12;

+   }

+   t += (j & 3) * 4;

+

+   decode_1[mode](code, t, rgba);

+}

+

+

+#endif /* FEATURE_texture_fxt1 */