+
+static void
+accum_return(GLcontext *ctx, GLfloat value,
+ GLint xpos, GLint ypos, GLint width, GLint height )
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ struct gl_framebuffer *fb = ctx->DrawBuffer;
+ struct gl_renderbuffer *accumRb = fb->Attachment[BUFFER_ACCUM].Renderbuffer;
+ const GLboolean directAccess
+ = (accumRb->GetPointer(ctx, accumRb, 0, 0) != NULL);
+ const GLboolean masking = (!ctx->Color.ColorMask[RCOMP] ||
+ !ctx->Color.ColorMask[GCOMP] ||
+ !ctx->Color.ColorMask[BCOMP] ||
+ !ctx->Color.ColorMask[ACOMP]);
+
+ static GLchan multTable[32768];
+ static GLfloat prevMult = 0.0;
+ const GLfloat mult = swrast->_IntegerAccumScaler;
+ const GLint max = MIN2((GLint) (256 / mult), 32767);
+
+ /* May have to leave optimized accum buffer mode */
+ if (swrast->_IntegerAccumMode && value != 1.0)
+ rescale_accum(ctx);
+
+ if (swrast->_IntegerAccumMode && swrast->_IntegerAccumScaler > 0) {
+ /* build lookup table to avoid many floating point multiplies */
+ GLint j;
+ assert(swrast->_IntegerAccumScaler <= 1.0);
+ if (mult != prevMult) {
+ for (j = 0; j < max; j++)
+ multTable[j] = IROUND((GLfloat) j * mult);
+ prevMult = mult;
+ }
+ }
+
+ if (accumRb->DataType == GL_SHORT ||
+ accumRb->DataType == GL_UNSIGNED_SHORT) {
+ const GLfloat scale = value * CHAN_MAXF / ACCUM_SCALE16;
+ GLuint buffer;
+ GLint i;
+
+ /* XXX maybe transpose the 'i' and 'buffer' loops??? */
+ for (i = 0; i < height; i++) {
+ GLshort accumRow[4 * MAX_WIDTH];
+ GLshort *acc;
+ SWspan span;
+
+ /* init color span */
+ INIT_SPAN(span, GL_BITMAP, width, 0, SPAN_RGBA);
+ span.x = xpos;
+ span.y = ypos + i;
+
+ if (directAccess) {
+ acc = (GLshort *) accumRb->GetPointer(ctx, accumRb, xpos, ypos +i);