texstore.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

               ASSERT(ctx->Pixel.Convolution1DEnabled);
               _mesa_convolve_1d_image(ctx, &convWidth, src, convImage);
            }
            else {
               if (ctx->Pixel.Convolution2DEnabled) {
                  _mesa_convolve_2d_image(ctx, &convWidth, &convHeight,
                                          src, convImage);
               }
               else {
                  ASSERT(ctx->Pixel.Separable2DEnabled);
                  _mesa_convolve_sep_image(ctx, &convWidth, &convHeight,
                                           src, convImage);
               }
            }
         }

         /* do post-convolution transfer and pack into tempImage */
         {
            const GLint logComponents
               = _mesa_components_in_format(logicalBaseFormat);
            const GLfloat *src = convImage;
            GLfloat *dst = tempImage + img * (convWidth * convHeight * 4);
            for (row = 0; row < convHeight; row++) {
               _mesa_pack_rgba_span_float(ctx, convWidth,
                                          (GLfloat (*)[4]) src,
                                          logicalBaseFormat, GL_FLOAT,
                                          dst, &ctx->DefaultPacking,
                                          postConvTransferOps);
               src += convWidth * 4;
               dst += convWidth * logComponents;
            }
         }
      } /* loop over 3D image slices */

      _mesa_free(convImage);

      /* might need these below */
      srcWidth = convWidth;
      srcHeight = convHeight;
   }
   else {
      /* no convolution */
      const GLint components = _mesa_components_in_format(logicalBaseFormat);
      const GLint srcStride = _mesa_image_row_stride(srcPacking,
                                                 srcWidth, srcFormat, srcType);
      GLfloat *dst;
      GLint img, row;

      tempImage = (GLfloat *) _mesa_malloc(srcWidth * srcHeight * srcDepth
                                           * components * sizeof(GLfloat));
      if (!tempImage)
         return NULL;

      dst = tempImage;
      for (img = 0; img < srcDepth; img++) {
         const GLubyte *src
            = (const GLubyte *) _mesa_image_address(dims, srcPacking, srcAddr,
                                                    srcWidth, srcHeight,
                                                    srcFormat, srcType,
                                                    img, 0, 0);
         for (row = 0; row < srcHeight; row++) {
            _mesa_unpack_color_span_float(ctx, srcWidth, logicalBaseFormat,
                                          dst, srcFormat, srcType, src,
                                          srcPacking, transferOps);
            dst += srcWidth * components;
            src += srcStride;
         }
      }
   }

   if (logicalBaseFormat != textureBaseFormat) {
      /* more work */
      GLint texComponents = _mesa_components_in_format(textureBaseFormat);
      GLint logComponents = _mesa_components_in_format(logicalBaseFormat);
      GLfloat *newImage;
      GLint i, n;
      GLubyte map[6];

      /* we only promote up to RGB, RGBA and LUMINANCE_ALPHA formats for now */
      ASSERT(textureBaseFormat == GL_RGB || textureBaseFormat == GL_RGBA ||
             textureBaseFormat == GL_LUMINANCE_ALPHA);

      /* The actual texture format should have at least as many components
       * as the logical texture format.
       */
      ASSERT(texComponents >= logComponents);

      newImage = (GLfloat *) _mesa_malloc(srcWidth * srcHeight * srcDepth
                                          * texComponents * sizeof(GLfloat));
      if (!newImage) {
         _mesa_free(tempImage);
         return NULL;
      }

      compute_component_mapping(logicalBaseFormat, textureBaseFormat, map);

      n = srcWidth * srcHeight * srcDepth;
      for (i = 0; i < n; i++) {
         GLint k;
         for (k = 0; k < texComponents; k++) {
            GLint j = map[k];
            if (j == ZERO)
               newImage[i * texComponents + k] = 0.0F;
            else if (j == ONE)
               newImage[i * texComponents + k] = 1.0F;
            else
               newImage[i * texComponents + k] = tempImage[i * logComponents + j];
         }
      }

      _mesa_free(tempImage);
      tempImage = newImage;
   }

   return tempImage;
}


/**
 * Make a temporary (color) texture image with GLchan components.
 * Apply all needed pixel unpacking and pixel transfer operations.
 * Note that there are both logicalBaseFormat and textureBaseFormat parameters.
 * Suppose the user specifies GL_LUMINANCE as the internal texture format
 * but the graphics hardware doesn't support luminance textures.  So, might
 * use an RGB hardware format instead.
 * If logicalBaseFormat != textureBaseFormat we have some extra work to do.
 *
 * \param ctx  the rendering context
 * \param dims  image dimensions: 1, 2 or 3
 * \param logicalBaseFormat  basic texture derived from the user's
 *    internal texture format value
 * \param textureBaseFormat  the actual basic format of the texture
 * \param srcWidth  source image width
 * \param srcHeight  source image height
 * \param srcDepth  source image depth
 * \param srcFormat  source image format
 * \param srcType  source image type
 * \param srcAddr  source image address
 * \param srcPacking  source image pixel packing
 * \return resulting image with format = textureBaseFormat and type = GLchan.
 */
GLchan *
_mesa_make_temp_chan_image(GLcontext *ctx, GLuint dims,
                           GLenum logicalBaseFormat,
                           GLenum textureBaseFormat,
                           GLint srcWidth, GLint srcHeight, GLint srcDepth,
                           GLenum srcFormat, GLenum srcType,
                           const GLvoid *srcAddr,
                           const struct gl_pixelstore_attrib *srcPacking)
{
   GLuint transferOps = ctx->_ImageTransferState;
   const GLint components = _mesa_components_in_format(logicalBaseFormat);
   GLboolean freeSrcImage = GL_FALSE;
   GLint img, row;
   GLchan *tempImage, *dst;

   ASSERT(dims >= 1 && dims <= 3);

   ASSERT(logicalBaseFormat == GL_RGBA ||
          logicalBaseFormat == GL_RGB ||
          logicalBaseFormat == GL_LUMINANCE_ALPHA ||
          logicalBaseFormat == GL_LUMINANCE ||
          logicalBaseFormat == GL_ALPHA ||
          logicalBaseFormat == GL_INTENSITY);

   ASSERT(textureBaseFormat == GL_RGBA ||
          textureBaseFormat == GL_RGB ||
          textureBaseFormat == GL_LUMINANCE_ALPHA ||
          textureBaseFormat == GL_LUMINANCE ||
          textureBaseFormat == GL_ALPHA ||
          textureBaseFormat == GL_INTENSITY);

   if ((dims == 1 && ctx->Pixel.Convolution1DEnabled) ||
       (dims >= 2 && ctx->Pixel.Convolution2DEnabled) ||
       (dims >= 2 && ctx->Pixel.Separable2DEnabled)) {
      /* get convolved image */
      GLfloat *convImage = make_temp_float_image(ctx, dims,
                                                 logicalBaseFormat,
                                                 logicalBaseFormat,
                                                 srcWidth, srcHeight, srcDepth,
                                                 srcFormat, srcType,
                                                 srcAddr, srcPacking);
      if (!convImage)
         return NULL;
      /* the convolved image is our new source image */
      srcAddr = convImage;
      srcFormat = logicalBaseFormat;
      srcType = GL_FLOAT;
      srcPacking = &ctx->DefaultPacking;
      _mesa_adjust_image_for_convolution(ctx, dims, &srcWidth, &srcHeight);
      transferOps = 0;
      freeSrcImage = GL_TRUE;
   }

   /* unpack and transfer the source image */
   tempImage = (GLchan *) _mesa_malloc(srcWidth * srcHeight * srcDepth
                                       * components * sizeof(GLchan));
   if (!tempImage)
      return NULL;

   dst = tempImage;
   for (img = 0; img < srcDepth; img++) {
      const GLint srcStride = _mesa_image_row_stride(srcPacking,
                                                     srcWidth, srcFormat,
                                                     srcType);
      const GLubyte *src
         = (const GLubyte *) _mesa_image_address(dims, srcPacking, srcAddr,
                                                 srcWidth, srcHeight,
                                                 srcFormat, srcType,
                                                 img, 0, 0);
      for (row = 0; row < srcHeight; row++) {
         _mesa_unpack_color_span_chan(ctx, srcWidth, logicalBaseFormat, dst,
                                      srcFormat, srcType, src, srcPacking,
                                      transferOps);
         dst += srcWidth * components;
         src += srcStride;
      }
   }

   /* If we made a temporary image for convolution, free it here */
   if (freeSrcImage) {
      _mesa_free((void *) srcAddr);
   }

   if (logicalBaseFormat != textureBaseFormat) {
      /* one more conversion step */
      GLint texComponents = _mesa_components_in_format(textureBaseFormat);
      GLint logComponents = _mesa_components_in_format(logicalBaseFormat);
      GLchan *newImage;
      GLint i, n;
      GLubyte map[6];

      /* we only promote up to RGB, RGBA and LUMINANCE_ALPHA formats for now */
      ASSERT(textureBaseFormat == GL_RGB || textureBaseFormat == GL_RGBA ||
             textureBaseFormat == GL_LUMINANCE_ALPHA);

      /* The actual texture format should have at least as many components
       * as the logical texture format.
       */
      ASSERT(texComponents >= logComponents);

      newImage = (GLchan *) _mesa_malloc(srcWidth * srcHeight * srcDepth
                                         * texComponents * sizeof(GLchan));
      if (!newImage) {
         _mesa_free(tempImage);
         return NULL;
      }

      compute_component_mapping(logicalBaseFormat, textureBaseFormat, map);

      n = srcWidth * srcHeight * srcDepth;
      for (i = 0; i < n; i++) {
         GLint k;
         for (k = 0; k < texComponents; k++) {
            GLint j = map[k];
            if (j == ZERO)
               newImage[i * texComponents + k] = 0;
            else if (j == ONE)
               newImage[i * texComponents + k] = CHAN_MAX;
            else
               newImage[i * texComponents + k] = tempImage[i * logComponents + j];
         }
      }

      _mesa_free(tempImage);
      tempImage = newImage;
   }

   return tempImage;
}


/**
 * Copy GLubyte pixels from <src> to <dst> with swizzling.
 * \param dst  destination pixels
 * \param dstComponents  number of color components in destination pixels
 * \param src  source pixels
 * \param srcComponents  number of color components in source pixels
 * \param map  the swizzle mapping.  map[X] says where to find the X component
 *             in the source image's pixels.  For example, if the source image
 *             is GL_BGRA and X = red, map[0] yields 2.
 * \param count  number of pixels to copy/swizzle.
 */
static void
swizzle_copy(GLubyte *dst, GLuint dstComponents, const GLubyte *src, 
             GLuint srcComponents, const GLubyte *map, GLuint count)
{
#define SWZ_CPY(dst, src, count, dstComps, srcComps) \
   do {                                              \
      GLuint i;                                      \
      for (i = 0; i < count; i++) {                  \
         GLuint j;                                   \
         if (srcComps == 4) {                        \
            COPY_4UBV(tmp, src);                     \
         }                                           \
         else {                                      \
            for (j = 0; j < srcComps; j++) {         \
               tmp[j] = src[j];                      \
            }                                        \
         }                                           \
         src += srcComps;                            \
         for (j = 0; j < dstComps; j++) {            \
            dst[j] = tmp[map[j]];                    \
         }                                           \
         dst += dstComps;                            \
      }                                              \
   } while (0)

   GLubyte tmp[6];

   tmp[ZERO] = 0x0;
   tmp[ONE] = 0xff;

   ASSERT(srcComponents <= 4);
   ASSERT(dstComponents <= 4);

   switch (dstComponents) {
   case 4:
      switch (srcComponents) {
      case 4:
         SWZ_CPY(dst, src, count, 4, 4);
         break;
      case 3:
         SWZ_CPY(dst, src, count, 4, 3);
         break;
      case 2:
         SWZ_CPY(dst, src, count, 4, 2);
         break;
      case 1:
         SWZ_CPY(dst, src, count, 4, 1);
         break;
      default:
         ;
      }
      break;
   case 3:
      switch (srcComponents) {
      case 4:
         SWZ_CPY(dst, src, count, 3, 4);
         break;
      case 3:
         SWZ_CPY(dst, src, count, 3, 3);
         break;
      case 2:
         SWZ_CPY(dst, src, count, 3, 2);
         break;
      case 1:
         SWZ_CPY(dst, src, count, 3, 1);
         break;
      default:
         ;
      }
      break;
   case 2:
      switch (srcComponents) {
      case 4:
         SWZ_CPY(dst, src, count, 2, 4);
         break;
      case 3:
         SWZ_CPY(dst, src, count, 2, 3);
         break;
      case 2:
         SWZ_CPY(dst, src, count, 2, 2);
         break;
      case 1:
         SWZ_CPY(dst, src, count, 2, 1);
         break;
      default:
         ;
      }
      break;
   case 1:
      switch (srcComponents) {
      case 4:
         SWZ_CPY(dst, src, count, 1, 4);
         break;
      case 3:
         SWZ_CPY(dst, src, count, 1, 3);