texcompress_fxt1.c

winNT技术操作系统,国外开放的原代码和LIUX一样

         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" */