image.c

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

 * by the dstFormat, dstType and dstPacking.  Used by glReadPixels,
 * glGetConvolutionFilter(), etc.
 * Incoming colors will be clamped to [0,1] if needed.
 * Note: the rgba values will be modified by this function when any pixel
 * transfer ops are enabled.
 */
void
_mesa_pack_rgba_span_float(GLcontext *ctx, GLuint n, GLfloat rgba[][4],
                           GLenum dstFormat, GLenum dstType,
                           GLvoid *dstAddr,
                           const struct gl_pixelstore_attrib *dstPacking,
                           GLbitfield transferOps)
{
   GLfloat luminance[MAX_WIDTH];
   const GLint comps = _mesa_components_in_format(dstFormat);
   GLuint i;

   if (dstType != GL_FLOAT || ctx->Color.ClampReadColor == GL_TRUE) {
      /* need to clamp to [0, 1] */
      transferOps |= IMAGE_CLAMP_BIT;
   }

   if (transferOps) {
      _mesa_apply_rgba_transfer_ops(ctx, transferOps, n, rgba);
      if ((transferOps & IMAGE_MIN_MAX_BIT) && ctx->MinMax.Sink) {
         return;
      }
   }

   if (dstFormat == GL_LUMINANCE || dstFormat == GL_LUMINANCE_ALPHA) {
      /* compute luminance values */
      if (dstType != GL_FLOAT || ctx->Color.ClampReadColor == GL_TRUE) {
         for (i = 0; i < n; i++) {
            GLfloat sum = rgba[i][RCOMP] + rgba[i][GCOMP] + rgba[i][BCOMP];
            luminance[i] = CLAMP(sum, 0.0F, 1.0F);
         }
      }
      else {
         for (i = 0; i < n; i++) {
            luminance[i] = rgba[i][RCOMP] + rgba[i][GCOMP] + rgba[i][BCOMP];
         }
      }
   }

   /*
    * Pack/store the pixels.  Ugh!  Lots of cases!!!
    */
   switch (dstType) {
      case GL_UNSIGNED_BYTE:
         {
            GLubyte *dst = (GLubyte *) dstAddr;
            switch (dstFormat) {
               case GL_RED:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UBYTE(rgba[i][RCOMP]);
                  break;
               case GL_GREEN:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UBYTE(rgba[i][GCOMP]);
                  break;
               case GL_BLUE:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UBYTE(rgba[i][BCOMP]);
                  break;
               case GL_ALPHA:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UBYTE(rgba[i][ACOMP]);
                  break;
               case GL_LUMINANCE:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UBYTE(luminance[i]);
                  break;
               case GL_LUMINANCE_ALPHA:
                  for (i=0;i<n;i++) {
                     dst[i*2+0] = FLOAT_TO_UBYTE(luminance[i]);
                     dst[i*2+1] = FLOAT_TO_UBYTE(rgba[i][ACOMP]);
                  }
                  break;
               case GL_RGB:
                  for (i=0;i<n;i++) {
                     dst[i*3+0] = FLOAT_TO_UBYTE(rgba[i][RCOMP]);
                     dst[i*3+1] = FLOAT_TO_UBYTE(rgba[i][GCOMP]);
                     dst[i*3+2] = FLOAT_TO_UBYTE(rgba[i][BCOMP]);
                  }
                  break;
               case GL_RGBA:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_UBYTE(rgba[i][RCOMP]);
                     dst[i*4+1] = FLOAT_TO_UBYTE(rgba[i][GCOMP]);
                     dst[i*4+2] = FLOAT_TO_UBYTE(rgba[i][BCOMP]);
                     dst[i*4+3] = FLOAT_TO_UBYTE(rgba[i][ACOMP]);
                  }
                  break;
               case GL_BGR:
                  for (i=0;i<n;i++) {
                     dst[i*3+0] = FLOAT_TO_UBYTE(rgba[i][BCOMP]);
                     dst[i*3+1] = FLOAT_TO_UBYTE(rgba[i][GCOMP]);
                     dst[i*3+2] = FLOAT_TO_UBYTE(rgba[i][RCOMP]);
                  }
                  break;
               case GL_BGRA:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_UBYTE(rgba[i][BCOMP]);
                     dst[i*4+1] = FLOAT_TO_UBYTE(rgba[i][GCOMP]);
                     dst[i*4+2] = FLOAT_TO_UBYTE(rgba[i][RCOMP]);
                     dst[i*4+3] = FLOAT_TO_UBYTE(rgba[i][ACOMP]);
                  }
                  break;
               case GL_ABGR_EXT:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_UBYTE(rgba[i][ACOMP]);
                     dst[i*4+1] = FLOAT_TO_UBYTE(rgba[i][BCOMP]);
                     dst[i*4+2] = FLOAT_TO_UBYTE(rgba[i][GCOMP]);
                     dst[i*4+3] = FLOAT_TO_UBYTE(rgba[i][RCOMP]);
                  }
                  break;
               default:
                  _mesa_problem(ctx, "bad format in _mesa_pack_rgba_span\n");
            }
         }
         break;
      case GL_BYTE:
         {
            GLbyte *dst = (GLbyte *) dstAddr;
            switch (dstFormat) {
               case GL_RED:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_BYTE(rgba[i][RCOMP]);
                  break;
               case GL_GREEN:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_BYTE(rgba[i][GCOMP]);
                  break;
               case GL_BLUE:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_BYTE(rgba[i][BCOMP]);
                  break;
               case GL_ALPHA:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_BYTE(rgba[i][ACOMP]);
                  break;
               case GL_LUMINANCE:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_BYTE(luminance[i]);
                  break;
               case GL_LUMINANCE_ALPHA:
                  for (i=0;i<n;i++) {
                     dst[i*2+0] = FLOAT_TO_BYTE(luminance[i]);
                     dst[i*2+1] = FLOAT_TO_BYTE(rgba[i][ACOMP]);
                  }
                  break;
               case GL_RGB:
                  for (i=0;i<n;i++) {
                     dst[i*3+0] = FLOAT_TO_BYTE(rgba[i][RCOMP]);
                     dst[i*3+1] = FLOAT_TO_BYTE(rgba[i][GCOMP]);
                     dst[i*3+2] = FLOAT_TO_BYTE(rgba[i][BCOMP]);
                  }
                  break;
               case GL_RGBA:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_BYTE(rgba[i][RCOMP]);
                     dst[i*4+1] = FLOAT_TO_BYTE(rgba[i][GCOMP]);
                     dst[i*4+2] = FLOAT_TO_BYTE(rgba[i][BCOMP]);
                     dst[i*4+3] = FLOAT_TO_BYTE(rgba[i][ACOMP]);
                  }
                  break;
               case GL_BGR:
                  for (i=0;i<n;i++) {
                     dst[i*3+0] = FLOAT_TO_BYTE(rgba[i][BCOMP]);
                     dst[i*3+1] = FLOAT_TO_BYTE(rgba[i][GCOMP]);
                     dst[i*3+2] = FLOAT_TO_BYTE(rgba[i][RCOMP]);
                  }
                  break;
               case GL_BGRA:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_BYTE(rgba[i][BCOMP]);
                     dst[i*4+1] = FLOAT_TO_BYTE(rgba[i][GCOMP]);
                     dst[i*4+2] = FLOAT_TO_BYTE(rgba[i][RCOMP]);
                     dst[i*4+3] = FLOAT_TO_BYTE(rgba[i][ACOMP]);
                  }
		  break;
               case GL_ABGR_EXT:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_BYTE(rgba[i][ACOMP]);
                     dst[i*4+1] = FLOAT_TO_BYTE(rgba[i][BCOMP]);
                     dst[i*4+2] = FLOAT_TO_BYTE(rgba[i][GCOMP]);
                     dst[i*4+3] = FLOAT_TO_BYTE(rgba[i][RCOMP]);
                  }
                  break;
               default:
                  _mesa_problem(ctx, "bad format in _mesa_pack_rgba_span\n");
            }
         }
         break;
      case GL_UNSIGNED_SHORT:
         {
            GLushort *dst = (GLushort *) dstAddr;
            switch (dstFormat) {
               case GL_RED:
                  for (i=0;i<n;i++)
                     CLAMPED_FLOAT_TO_USHORT(dst[i], rgba[i][RCOMP]);
                  break;
               case GL_GREEN:
                  for (i=0;i<n;i++)
                     CLAMPED_FLOAT_TO_USHORT(dst[i], rgba[i][GCOMP]);
                  break;
               case GL_BLUE:
                  for (i=0;i<n;i++)
                     CLAMPED_FLOAT_TO_USHORT(dst[i], rgba[i][BCOMP]);
                  break;
               case GL_ALPHA:
                  for (i=0;i<n;i++)
                     CLAMPED_FLOAT_TO_USHORT(dst[i], rgba[i][ACOMP]);
                  break;
               case GL_LUMINANCE:
                  for (i=0;i<n;i++)
                     UNCLAMPED_FLOAT_TO_USHORT(dst[i], luminance[i]);
                  break;
               case GL_LUMINANCE_ALPHA:
                  for (i=0;i<n;i++) {
                     UNCLAMPED_FLOAT_TO_USHORT(dst[i*2+0], luminance[i]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*2+1], rgba[i][ACOMP]);
                  }
                  break;
               case GL_RGB:
                  for (i=0;i<n;i++) {
                     CLAMPED_FLOAT_TO_USHORT(dst[i*3+0], rgba[i][RCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*3+1], rgba[i][GCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*3+2], rgba[i][BCOMP]);
                  }
                  break;
               case GL_RGBA:
                  for (i=0;i<n;i++) {
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+0], rgba[i][RCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+1], rgba[i][GCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+2], rgba[i][BCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+3], rgba[i][ACOMP]);
                  }
                  break;
               case GL_BGR:
                  for (i=0;i<n;i++) {
                     CLAMPED_FLOAT_TO_USHORT(dst[i*3+0], rgba[i][BCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*3+1], rgba[i][GCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*3+2], rgba[i][RCOMP]);
                  }
                  break;
               case GL_BGRA:
                  for (i=0;i<n;i++) {
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+0], rgba[i][BCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+1], rgba[i][GCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+2], rgba[i][RCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+3], rgba[i][ACOMP]);
                  }
                  break;
               case GL_ABGR_EXT:
                  for (i=0;i<n;i++) {
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+0], rgba[i][ACOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+1], rgba[i][BCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+2], rgba[i][GCOMP]);
                     CLAMPED_FLOAT_TO_USHORT(dst[i*4+3], rgba[i][RCOMP]);
                  }
                  break;
               default:
                  _mesa_problem(ctx, "bad format in _mesa_pack_rgba_span\n");
            }
         }
         break;
      case GL_SHORT:
         {
            GLshort *dst = (GLshort *) dstAddr;
            switch (dstFormat) {
               case GL_RED:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_SHORT(rgba[i][RCOMP]);
                  break;
               case GL_GREEN:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_SHORT(rgba[i][GCOMP]);
                  break;
               case GL_BLUE:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_SHORT(rgba[i][BCOMP]);
                  break;
               case GL_ALPHA:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_SHORT(rgba[i][ACOMP]);
                  break;
               case GL_LUMINANCE:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_SHORT(luminance[i]);
                  break;
               case GL_LUMINANCE_ALPHA:
                  for (i=0;i<n;i++) {
                     dst[i*2+0] = FLOAT_TO_SHORT(luminance[i]);
                     dst[i*2+1] = FLOAT_TO_SHORT(rgba[i][ACOMP]);
                  }
                  break;
               case GL_RGB:
                  for (i=0;i<n;i++) {
                     dst[i*3+0] = FLOAT_TO_SHORT(rgba[i][RCOMP]);
                     dst[i*3+1] = FLOAT_TO_SHORT(rgba[i][GCOMP]);
                     dst[i*3+2] = FLOAT_TO_SHORT(rgba[i][BCOMP]);
                  }
                  break;
               case GL_RGBA:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_SHORT(rgba[i][RCOMP]);
                     dst[i*4+1] = FLOAT_TO_SHORT(rgba[i][GCOMP]);
                     dst[i*4+2] = FLOAT_TO_SHORT(rgba[i][BCOMP]);
                     dst[i*4+3] = FLOAT_TO_SHORT(rgba[i][ACOMP]);
                  }
                  break;
               case GL_BGR:
                  for (i=0;i<n;i++) {
                     dst[i*3+0] = FLOAT_TO_SHORT(rgba[i][BCOMP]);
                     dst[i*3+1] = FLOAT_TO_SHORT(rgba[i][GCOMP]);
                     dst[i*3+2] = FLOAT_TO_SHORT(rgba[i][RCOMP]);
                  }
                  break;
               case GL_BGRA:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_SHORT(rgba[i][BCOMP]);
                     dst[i*4+1] = FLOAT_TO_SHORT(rgba[i][GCOMP]);
                     dst[i*4+2] = FLOAT_TO_SHORT(rgba[i][RCOMP]);
                     dst[i*4+3] = FLOAT_TO_SHORT(rgba[i][ACOMP]);
                  }
		  break;
               case GL_ABGR_EXT:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_SHORT(rgba[i][ACOMP]);
                     dst[i*4+1] = FLOAT_TO_SHORT(rgba[i][BCOMP]);
                     dst[i*4+2] = FLOAT_TO_SHORT(rgba[i][GCOMP]);
                     dst[i*4+3] = FLOAT_TO_SHORT(rgba[i][RCOMP]);
                  }
                  break;
               default:
                  _mesa_problem(ctx, "bad format in _mesa_pack_rgba_span\n");
            }
         }
         break;
      case GL_UNSIGNED_INT:
         {
            GLuint *dst = (GLuint *) dstAddr;
            switch (dstFormat) {
               case GL_RED:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UINT(rgba[i][RCOMP]);
                  break;
               case GL_GREEN:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UINT(rgba[i][GCOMP]);
                  break;
               case GL_BLUE:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UINT(rgba[i][BCOMP]);
                  break;
               case GL_ALPHA:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UINT(rgba[i][ACOMP]);
                  break;
               case GL_LUMINANCE:
                  for (i=0;i<n;i++)
                     dst[i] = FLOAT_TO_UINT(luminance[i]);
                  break;
               case GL_LUMINANCE_ALPHA:
                  for (i=0;i<n;i++) {
                     dst[i*2+0] = FLOAT_TO_UINT(luminance[i]);
                     dst[i*2+1] = FLOAT_TO_UINT(rgba[i][ACOMP]);
                  }
                  break;
               case GL_RGB:
                  for (i=0;i<n;i++) {
                     dst[i*3+0] = FLOAT_TO_UINT(rgba[i][RCOMP]);
                     dst[i*3+1] = FLOAT_TO_UINT(rgba[i][GCOMP]);
                     dst[i*3+2] = FLOAT_TO_UINT(rgba[i][BCOMP]);
                  }
                  break;
               case GL_RGBA:
                  for (i=0;i<n;i++) {
                     dst[i*4+0] = FLOAT_TO_UINT(rgba[i][RCOMP]);
                     dst[i*4+1] = FLOAT_TO_UINT(rgba[i][GCOMP]);
                     dst[i*4+2] = FLOAT_TO_UINT(rgba[i][BCOMP]);
                     dst[i*4+3] = FLOAT_TO_UINT(rgba[i][ACOMP]);
                  }
                  break;
               case GL_BGR:
                  for (i=0;i<n;i++) {
                     dst[i*3+0] = FLOAT_TO_UINT(rgba[i][BCOMP]);
                     dst[i*3+1] = FLOAT_TO_UINT(rgba[i][GCOMP]);
                     dst[i*3+2] = FLOAT_TO_UINT(rgba[i][RCOMP]);
                  }
                  break;
               case GL_BGRA: