texstore.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

                                          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
 * \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)
{
   GLubyte tmp[8];
   GLint i;

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

   switch (dstComponents) {
   case 4:
      for (i = 0; i < count; i++) {
 	 COPY_4UBV(tmp, src); 
	 src += srcComponents;      
	 dst[0] = tmp[map[0]];
	 dst[1] = tmp[map[1]];
	 dst[2] = tmp[map[2]];
	 dst[3] = tmp[map[3]];
	 dst += 4;
      }
      break;
   case 3:
      for (i = 0; i < count; i++) {
 	 COPY_4UBV(tmp, src); 
	 src += srcComponents;      
	 dst[0] = tmp[map[0]];
	 dst[1] = tmp[map[1]];
	 dst[2] = tmp[map[2]];
	 dst += 3;
      }
      break;
   case 2:
      for (i = 0; i < count; i++) {
 	 COPY_4UBV(tmp, src); 
	 src += srcComponents;      
	 dst[0] = tmp[map[0]];
	 dst[1] = tmp[map[1]];
	 dst += 2;
      }
      break;
   }
}


/**
 * Transfer a GLubyte texture image with component swizzling.
 */
static void
_mesa_swizzle_ubyte_image(GLcontext *ctx, 
			  GLuint dimensions,
			  GLenum srcFormat,
			  const GLubyte *dstmap, GLint dstComponents,

			  GLvoid *dstAddr,
			  GLint dstXoffset, GLint dstYoffset, GLint dstZoffset,
			  GLint dstRowStride, GLint dstImageStride,

			  GLint srcWidth, GLint srcHeight, GLint srcDepth,
			  const GLvoid *srcAddr,
			  const struct gl_pixelstore_attrib *srcPacking )
{
   GLint srcComponents = _mesa_components_in_format(srcFormat);
   GLubyte srcmap[6], map[4];
   GLint i;

   const GLint srcRowStride =
      _mesa_image_row_stride(srcPacking, srcWidth,
                             srcFormat, GL_UNSIGNED_BYTE);
   const GLint srcImageStride
      = _mesa_image_image_stride(srcPacking, srcWidth, srcHeight, srcFormat,
                                 GL_UNSIGNED_BYTE);
   const GLubyte *srcImage
      = (const GLubyte *) _mesa_image_address(dimensions, srcPacking, srcAddr,
                                              srcWidth, srcHeight, srcFormat,
                                              GL_UNSIGNED_BYTE, 0, 0, 0);

   GLubyte *dstImage = (GLubyte *) dstAddr
                     + dstZoffset * dstImageStride
                     + dstYoffset * dstRowStride
                     + dstXoffset * dstComponents;

   compute_component_mapping(srcFormat, GL_RGBA, srcmap);

   for (i = 0; i < 4; i++)
      map[i] = srcmap[dstmap[i]];

   if (srcRowStride == srcWidth * srcComponents &&
       (srcImageStride == srcWidth * srcHeight * srcComponents ||
        srcDepth == 1)) {
      swizzle_copy(dstImage, dstComponents, srcImage, srcComponents, map, 
		   srcWidth * srcHeight * srcDepth);
   }
   else {
      GLint img, row;
      for (img = 0; img < srcDepth; img++) {
         const GLubyte *srcRow = srcImage;
         GLubyte *dstRow = dstImage;
         for (row = 0; row < srcHeight; row++) {
	    swizzle_copy(dstRow, dstComponents, srcRow, srcComponents, map, srcWidth);
            dstRow += dstRowStride;
            srcRow += srcRowStride;
         }
         srcImage += srcImageStride;
         dstImage += dstImageStride;
      }
   }
}


/**
 * Teximage storage routine for when a simple memcpy will do.
 * No pixel transfer operations or special texel encodings allowed.
 * 1D, 2D and 3D images supported.
 */
static void
memcpy_texture(GLcontext *ctx,
	       GLuint dimensions,
               const struct gl_texture_format *dstFormat,