static void accum_accum	(	GLcontext *	ctx,
		GLfloat	value,
		GLint	xpos,
		GLint	ypos,
		GLint	width,
		GLint	height
	)		`[static]`
Definition at line 273 of file s_accum.c.
Referenced by _swrast_Accum().
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   struct gl_renderbuffer *rb
      = ctx->DrawBuffer->Attachment[BUFFER_ACCUM].Renderbuffer;
   const GLboolean directAccess = (rb->GetPointer(ctx, rb, 0, 0) != NULL);

   assert(rb);

   if (!ctx->ReadBuffer->_ColorReadBuffer) {
      /* no read buffer - OK */
      return;
   }

   /* May have to leave optimized accum buffer mode */
   if (swrast->_IntegerAccumScaler == 0.0 && value > 0.0 && value <= 1.0)
      swrast->_IntegerAccumScaler = value;
   if (swrast->_IntegerAccumMode && value != swrast->_IntegerAccumScaler)
      rescale_accum(ctx);

   if (rb->DataType == GL_SHORT || rb->DataType == GL_UNSIGNED_SHORT) {
      const GLfloat scale = value * ACCUM_SCALE16 / CHAN_MAXF;
      GLshort accumRow[4 * MAX_WIDTH];
      GLchan rgba[MAX_WIDTH][4];
      GLint i;

      for (i = 0; i < height; i++) {
         GLshort *acc;
         if (directAccess) {
            acc = (GLshort *) rb->GetPointer(ctx, rb, xpos, ypos + i);
         }
         else {
            rb->GetRow(ctx, rb, width, xpos, ypos + i, accumRow);
            acc = accumRow;
         }

         /* read colors from color buffer */
         _swrast_read_rgba_span(ctx, ctx->ReadBuffer->_ColorReadBuffer, width,
                                xpos, ypos + i, CHAN_TYPE, rgba);

         /* do accumulation */
         if (swrast->_IntegerAccumMode) {
            /* simply add integer color values into accum buffer */
            GLint j;
            for (j = 0; j < width; j++) {
               acc[j * 4 + 0] += rgba[j][RCOMP];
               acc[j * 4 + 1] += rgba[j][GCOMP];
               acc[j * 4 + 2] += rgba[j][BCOMP];
               acc[j * 4 + 3] += rgba[j][ACOMP];
            }
         }
         else {
            /* scaled integer (or float) accum buffer */
            GLint j;
            for (j = 0; j < width; j++) {
               acc[j * 4 + 0] += (GLshort) ((GLfloat) rgba[j][RCOMP] * scale);
               acc[j * 4 + 1] += (GLshort) ((GLfloat) rgba[j][GCOMP] * scale);
               acc[j * 4 + 2] += (GLshort) ((GLfloat) rgba[j][BCOMP] * scale);
               acc[j * 4 + 3] += (GLshort) ((GLfloat) rgba[j][ACOMP] * scale);
            }
         }

         if (!directAccess) {
            rb->PutRow(ctx, rb, width, xpos, ypos + i, accumRow, NULL);
         }
      }
   }
   else {
      /* other types someday */
   }
}
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