svn merge ^/branches/released . --username marha

1 files changed, 1724 insertions, 0 deletions

diff --git a/mesalib/src/mesa/main/texcompress_fxt1.c b/mesalib/src/mesa/main/texcompress_fxt1.c
new file mode 100644
index 000000000..fc151605c
--- /dev/null
+++ b/mesalib/src/mesa/main/texcompress_fxt1.c
@@ -0,0 +1,1724 @@
+/*
+ * 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 "context.h"
+#include "convolve.h"
+#include "image.h"
+#include "mipmap.h"
+#include "texcompress.h"
+#include "texformat.h"
+#include "texstore.h"
+
+
+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);
+
+
+/**
+ * Called during context initialization.
+ */
+void
+_mesa_init_texture_fxt1( GLcontext *ctx )
+{
+   (void) ctx;
+}
+
+
+/**
+ * Called via TexFormat->StoreImage to store an RGB_FXT1 texture.
+ */
+static GLboolean
+texstore_rgb_fxt1(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_texformat_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,
+                                             dstFormat->BaseFormat,
+                                             srcWidth, srcHeight, srcDepth,
+                                             srcFormat, srcType, srcAddr,
+                                             srcPacking);
+      if (!tempImage)
+         return GL_FALSE; /* out of memory */
+      _mesa_adjust_image_for_convolution(ctx, dims, &srcWidth, &srcHeight);
+      pixels = tempImage;
+      srcRowStride = 3 * srcWidth;
+      srcFormat = GL_RGB;
+   }
+   else {
+      pixels = (const GLchan *) srcAddr;
+      srcRowStride = _mesa_image_row_stride(srcPacking, srcWidth, srcFormat,
+                                            srcType) / sizeof(GLchan);
+   }
+
+   dst = _mesa_compressed_image_address(dstXoffset, dstYoffset, 0,
+                                        dstFormat->MesaFormat,
+                                        texWidth, (GLubyte *) dstAddr);
+
+   fxt1_encode(srcWidth, srcHeight, 3, pixels, srcRowStride,
+               dst, dstRowStride);
+
+   if (tempImage)
+      _mesa_free((void*) tempImage);
+
+   return GL_TRUE;
+}
+
+
+/**
+ * Called via TexFormat->StoreImage to store an RGBA_FXT1 texture.
+ */
+static GLboolean
+texstore_rgba_fxt1(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_texformat_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,
+                                             dstFormat->BaseFormat,
+                                             srcWidth, srcHeight, srcDepth,
+                                             srcFormat, srcType, srcAddr,
+                                             srcPacking);
+      if (!tempImage)
+         return GL_FALSE; /* out of memory */
+      _mesa_adjust_image_for_convolution(ctx, dims, &srcWidth, &srcHeight);
+      pixels = tempImage;
+      srcRowStride = 4 * srcWidth;
+      srcFormat = GL_RGBA;
+   }
+   else {
+      pixels = (const GLchan *) srcAddr;
+      srcRowStride = _mesa_image_row_stride(srcPacking, srcWidth, srcFormat,
+                                            srcType) / sizeof(GLchan);
+   }
+
+   dst = _mesa_compressed_image_address(dstXoffset, dstYoffset, 0,
+                                        dstFormat->MesaFormat,
+                                        texWidth, (GLubyte *) dstAddr);
+
+   fxt1_encode(srcWidth, srcHeight, 4, pixels, srcRowStride,
+               dst, dstRowStride);
+
+   if (tempImage)
+      _mesa_free((void*) tempImage);
+
+   return GL_TRUE;
+}
+
+
+static void
+fetch_texel_2d_rgba_fxt1( const struct gl_texture_image *texImage,
+                          GLint i, GLint j, GLint k, GLchan *texel )
+{
+   (void) k;
+   fxt1_decode_1(texImage->Data, texImage->RowStride, i, j, texel);
+}
+
+
+static void
+fetch_texel_2d_f_rgba_fxt1( const struct gl_texture_image *texImage,
+                            GLint i, GLint j, GLint k, GLfloat *texel )
+{
+   /* just sample as GLchan and convert to float here */
+   GLchan rgba[4];
+   (void) k;
+   fxt1_decode_1(texImage->Data, texImage->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]);
+}
+
+
+static void
+fetch_texel_2d_rgb_fxt1( const struct gl_texture_image *texImage,
+                         GLint i, GLint j, GLint k, GLchan *texel )
+{
+   (void) k;
+   fxt1_decode_1(texImage->Data, texImage->RowStride, i, j, texel);
+   texel[ACOMP] = 255;
+}
+
+
+static void
+fetch_texel_2d_f_rgb_fxt1( const struct gl_texture_image *texImage,
+                           GLint i, GLint j, GLint k, GLfloat *texel )
+{
+   /* just sample as GLchan and convert to float here */
+   GLchan rgba[4];
+   (void) k;
+   fxt1_decode_1(texImage->Data, texImage->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;
+}
+
+
+
+const struct gl_texture_format _mesa_texformat_rgb_fxt1 = {
+   MESA_FORMAT_RGB_FXT1,		/* MesaFormat */
+   GL_RGB,				/* BaseFormat */
+   GL_UNSIGNED_NORMALIZED_ARB,		/* DataType */
+   4, /*approx*/			/* RedBits */
+   4, /*approx*/			/* GreenBits */
+   4, /*approx*/			/* BlueBits */
+   0,					/* AlphaBits */
+   0,					/* LuminanceBits */
+   0,					/* IntensityBits */
+   0,					/* IndexBits */
+   0,					/* DepthBits */
+   0,					/* StencilBits */
+   0,					/* TexelBytes */
+   texstore_rgb_fxt1,			/* StoreTexImageFunc */
+   NULL, /*impossible*/ 		/* FetchTexel1D */
+   fetch_texel_2d_rgb_fxt1, 		/* FetchTexel2D */
+   NULL, /*impossible*/ 		/* FetchTexel3D */
+   NULL, /*impossible*/ 		/* FetchTexel1Df */
+   fetch_texel_2d_f_rgb_fxt1, 		/* FetchTexel2Df */
+   NULL, /*impossible*/ 		/* FetchTexel3Df */
+   NULL					/* StoreTexel */
+};
+
+const struct gl_texture_format _mesa_texformat_rgba_fxt1 = {
+   MESA_FORMAT_RGBA_FXT1,		/* MesaFormat */
+   GL_RGBA,				/* BaseFormat */
+   GL_UNSIGNED_NORMALIZED_ARB,		/* DataType */
+   4, /*approx*/			/* RedBits */
+   4, /*approx*/			/* GreenBits */
+   4, /*approx*/			/* BlueBits */
+   1, /*approx*/			/* AlphaBits */
+   0,					/* LuminanceBits */
+   0,					/* IntensityBits */
+   0,					/* IndexBits */
+   0,					/* DepthBits */
+   0,					/* StencilBits */
+   0,					/* TexelBytes */
+   texstore_rgba_fxt1,			/* StoreTexImageFunc */
+   NULL, /*impossible*/ 		/* FetchTexel1D */
+   fetch_texel_2d_rgba_fxt1, 		/* FetchTexel2D */
+   NULL, /*impossible*/ 		/* FetchTexel3D */
+   NULL, /*impossible*/ 		/* FetchTexel1Df */
+   fetch_texel_2d_f_rgba_fxt1, 		/* FetchTexel2Df */
+   NULL, /*impossible*/ 		/* FetchTexel3Df */
+   NULL					/* StoreTexel */
+};
+
+
+/***************************************************************************\
+ * 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;
+
+   _mesa_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 it's matching colors.
+    *
+    *     repeat until RMS doesn't improve.
+    *
+    *     if a color vector has no samples, or becomes the same as another
+    *     vector, replace it with the color which is farthest from a sample.
+    *
+    * vec[][MAX_COMP]           initial vectors and resulting colors
+    * nv                        number of resulting colors required
+    * input[N_TEXELS][MAX_COMP] input texels
+    * nc                        number of components in input / vec
+    * n                         number of input samples
+    */
+
+   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
+         /* 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 */
+      _mesa_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 = _mesa_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 *) _mesa_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) {
+         _mesa_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) {
+      _mesa_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);
+}