intel_tex_format.c

mesa-6.5-minigui源码

#include "intel_context.h"
#include "intel_tex.h"
#include "texformat.h"
#include "enums.h"

/* It works out that this function is fine for all the supported
 * hardware.  However, there is still a need to map the formats onto
 * hardware descriptors.
 */
/* Note that the i915 can actually support many more formats than
 * these if we take the step of simply swizzling the colors
 * immediately after sampling...
 */
const struct gl_texture_format *
intelChooseTextureFormat( GLcontext *ctx, GLint internalFormat,
                          GLenum format, GLenum type )
{
   struct intel_context *intel = intel_context( ctx );
   const GLboolean do32bpt = (intel->intelScreen->cpp == 4);

   switch ( internalFormat ) {
   case 4:
   case GL_RGBA:
   case GL_COMPRESSED_RGBA:
      if ( format == GL_BGRA ) {
	 if ( type == GL_UNSIGNED_INT_8_8_8_8_REV ) {
	    return &_mesa_texformat_argb8888;
	 }
         else if ( type == GL_UNSIGNED_SHORT_4_4_4_4_REV ) {
            return &_mesa_texformat_argb4444;
	 }
         else if ( type == GL_UNSIGNED_SHORT_1_5_5_5_REV ) {
	    return &_mesa_texformat_argb1555;
	 }
      }
      return do32bpt ? &_mesa_texformat_argb8888 : &_mesa_texformat_argb4444;

   case 3:
   case GL_RGB:
   case GL_COMPRESSED_RGB:
      if ( format == GL_RGB && type == GL_UNSIGNED_SHORT_5_6_5 ) {
	 return &_mesa_texformat_rgb565;
      }
      return do32bpt ? &_mesa_texformat_argb8888 : &_mesa_texformat_rgb565;

   case GL_RGBA8:
   case GL_RGB10_A2:
   case GL_RGBA12:
   case GL_RGBA16:
      return do32bpt ? &_mesa_texformat_argb8888 : &_mesa_texformat_argb4444;

   case GL_RGBA4:
   case GL_RGBA2:
      return &_mesa_texformat_argb4444;

   case GL_RGB5_A1:
      return &_mesa_texformat_argb1555;

   case GL_RGB8:
   case GL_RGB10:
   case GL_RGB12:
   case GL_RGB16:
      return &_mesa_texformat_argb8888;

   case GL_RGB5:
   case GL_RGB4:
   case GL_R3_G3_B2:
      return &_mesa_texformat_rgb565;

   case GL_ALPHA:
   case GL_ALPHA4:
   case GL_ALPHA8:
   case GL_ALPHA12:
   case GL_ALPHA16:
   case GL_COMPRESSED_ALPHA:
      return &_mesa_texformat_a8;

   case 1:
   case GL_LUMINANCE:
   case GL_LUMINANCE4:
   case GL_LUMINANCE8:
   case GL_LUMINANCE12:
   case GL_LUMINANCE16:
   case GL_COMPRESSED_LUMINANCE:
      return &_mesa_texformat_l8;

   case 2:
   case GL_LUMINANCE_ALPHA:
   case GL_LUMINANCE4_ALPHA4:
   case GL_LUMINANCE6_ALPHA2:
   case GL_LUMINANCE8_ALPHA8:
   case GL_LUMINANCE12_ALPHA4:
   case GL_LUMINANCE12_ALPHA12:
   case GL_LUMINANCE16_ALPHA16:
   case GL_COMPRESSED_LUMINANCE_ALPHA:
      return &_mesa_texformat_al88;

   case GL_INTENSITY:
   case GL_INTENSITY4:
   case GL_INTENSITY8:
   case GL_INTENSITY12:
   case GL_INTENSITY16:
   case GL_COMPRESSED_INTENSITY:
      return &_mesa_texformat_i8;

   case GL_YCBCR_MESA:
      if (type == GL_UNSIGNED_SHORT_8_8_MESA ||
	  type == GL_UNSIGNED_BYTE)
         return &_mesa_texformat_ycbcr;
      else
         return &_mesa_texformat_ycbcr_rev;

   case GL_COMPRESSED_RGB_FXT1_3DFX:
     return &_mesa_texformat_rgb_fxt1;
   case GL_COMPRESSED_RGBA_FXT1_3DFX:
     return &_mesa_texformat_rgba_fxt1;

   case GL_RGB_S3TC:
   case GL_RGB4_S3TC:
   case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
     return &_mesa_texformat_rgb_dxt1;

   case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
     return &_mesa_texformat_rgba_dxt1;

   case GL_RGBA_S3TC:
   case GL_RGBA4_S3TC:
   case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
     return &_mesa_texformat_rgba_dxt3;

   case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
      return &_mesa_texformat_rgba_dxt5;

   case GL_DEPTH_COMPONENT:
   case GL_DEPTH_COMPONENT16:
   case GL_DEPTH_COMPONENT24:
   case GL_DEPTH_COMPONENT32:
      return &_mesa_texformat_depth_component16;

   default:
      fprintf(stderr, "unexpected texture format %s in %s\n", 
	      _mesa_lookup_enum_by_nr(internalFormat),
	      __FUNCTION__);
      return NULL;
   }

   return NULL; /* never get here */
}