s_tritemp.h

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

                  zRow = (DEPTH_TYPE *)
                    zrb->GetPointer(ctx, zrb, FixedToInt(fxLeftEdge), span.y);
                  dZRowOuter = (ctx->DrawBuffer->Width + idxOuter) * sizeof(DEPTH_TYPE);
#  endif
               }
#endif
#ifdef INTERP_RGB
               if (ctx->Light.ShadeModel == GL_SMOOTH) {
                  rLeft = (GLint)(ChanToFixed(vLower->color[RCOMP])
                                  + span.attrStepX[FRAG_ATTRIB_COL0][0] * adjx
                                  + span.attrStepY[FRAG_ATTRIB_COL0][0] * adjy) + FIXED_HALF;
                  gLeft = (GLint)(ChanToFixed(vLower->color[GCOMP])
                                  + span.attrStepX[FRAG_ATTRIB_COL0][1] * adjx
                                  + span.attrStepY[FRAG_ATTRIB_COL0][1] * adjy) + FIXED_HALF;
                  bLeft = (GLint)(ChanToFixed(vLower->color[BCOMP])
                                  + span.attrStepX[FRAG_ATTRIB_COL0][2] * adjx
                                  + span.attrStepY[FRAG_ATTRIB_COL0][2] * adjy) + FIXED_HALF;
                  fdrOuter = SignedFloatToFixed(span.attrStepY[FRAG_ATTRIB_COL0][0]
                                                + dxOuter * span.attrStepX[FRAG_ATTRIB_COL0][0]);
                  fdgOuter = SignedFloatToFixed(span.attrStepY[FRAG_ATTRIB_COL0][1]
                                                + dxOuter * span.attrStepX[FRAG_ATTRIB_COL0][1]);
                  fdbOuter = SignedFloatToFixed(span.attrStepY[FRAG_ATTRIB_COL0][2]
                                                + dxOuter * span.attrStepX[FRAG_ATTRIB_COL0][2]);
#  ifdef INTERP_ALPHA
                  aLeft = (GLint)(ChanToFixed(vLower->color[ACOMP])
                                  + span.attrStepX[FRAG_ATTRIB_COL0][3] * adjx
                                  + span.attrStepY[FRAG_ATTRIB_COL0][3] * adjy) + FIXED_HALF;
                  fdaOuter = SignedFloatToFixed(span.attrStepY[FRAG_ATTRIB_COL0][3]
                                                + dxOuter * span.attrStepX[FRAG_ATTRIB_COL0][3]);
#  endif
               }
               else {
                  ASSERT(ctx->Light.ShadeModel == GL_FLAT);
                  rLeft = ChanToFixed(v2->color[RCOMP]);
                  gLeft = ChanToFixed(v2->color[GCOMP]);
                  bLeft = ChanToFixed(v2->color[BCOMP]);
                  fdrOuter = fdgOuter = fdbOuter = 0;
#  ifdef INTERP_ALPHA
                  aLeft = ChanToFixed(v2->color[ACOMP]);
                  fdaOuter = 0;
#  endif
               }
#endif /* INTERP_RGB */


#ifdef INTERP_INDEX
               if (ctx->Light.ShadeModel == GL_SMOOTH) {
                  iLeft = (GLfixed)(vLower->attrib[FRAG_ATTRIB_CI][0] * FIXED_SCALE
                                 + didx * adjx + didy * adjy) + FIXED_HALF;
                  diOuter = SignedFloatToFixed(didy + dxOuter * didx);
               }
               else {
                  ASSERT(ctx->Light.ShadeModel == GL_FLAT);
                  iLeft = FloatToFixed(v2->attrib[FRAG_ATTRIB_CI][0]);
                  diOuter = 0;
               }
#endif
#ifdef INTERP_INT_TEX
               {
                  GLfloat s0, t0;
                  s0 = vLower->attrib[FRAG_ATTRIB_TEX0][0] * S_SCALE;
                  sLeft = (GLfixed)(s0 * FIXED_SCALE + span.attrStepX[FRAG_ATTRIB_TEX0][0] * adjx
                                 + span.attrStepY[FRAG_ATTRIB_TEX0][0] * adjy) + FIXED_HALF;
                  dsOuter = SignedFloatToFixed(span.attrStepY[FRAG_ATTRIB_TEX0][0]
                                               + dxOuter * span.attrStepX[FRAG_ATTRIB_TEX0][0]);

                  t0 = vLower->attrib[FRAG_ATTRIB_TEX0][1] * T_SCALE;
                  tLeft = (GLfixed)(t0 * FIXED_SCALE + span.attrStepX[FRAG_ATTRIB_TEX0][1] * adjx
                                 + span.attrStepY[FRAG_ATTRIB_TEX0][1] * adjy) + FIXED_HALF;
                  dtOuter = SignedFloatToFixed(span.attrStepY[FRAG_ATTRIB_TEX0][1]
                                               + dxOuter * span.attrStepX[FRAG_ATTRIB_TEX0][1]);
               }
#endif
#ifdef INTERP_ATTRIBS
               {
                  const GLuint attr = FRAG_ATTRIB_WPOS;
                  wLeft = vLower->attrib[FRAG_ATTRIB_WPOS][3]
                        + (span.attrStepX[attr][3] * adjx
                           + span.attrStepY[attr][3] * adjy) * (1.0F/FIXED_SCALE);
                  dwOuter = span.attrStepY[attr][3] + dxOuter * span.attrStepX[attr][3];
               }
               ATTRIB_LOOP_BEGIN
                  const GLfloat invW = vLower->attrib[FRAG_ATTRIB_WPOS][3];
                  if (swrast->_InterpMode[attr] == GL_FLAT) {
                     GLuint c;
                     for (c = 0; c < 4; c++) {
                        attrLeft[attr][c] = v2->attrib[attr][c] * invW;
                        daOuter[attr][c] = 0.0;
                     }
                  }
                  else {
                     GLuint c;
                     for (c = 0; c < 4; c++) {
                        const GLfloat a = vLower->attrib[attr][c] * invW;
                        attrLeft[attr][c] = a + (  span.attrStepX[attr][c] * adjx
                                                 + span.attrStepY[attr][c] * adjy) * (1.0F/FIXED_SCALE);
                        daOuter[attr][c] = span.attrStepY[attr][c] + dxOuter * span.attrStepX[attr][c];
                     }
                  }
               ATTRIB_LOOP_END
#endif
            } /*if setupLeft*/


            if (setupRight && eRight->lines>0) {
               fxRightEdge = eRight->fsx - FIXED_EPSILON;
               fdxRightEdge = eRight->fdxdy;
            }

            if (lines==0) {
               continue;
            }


            /* Rasterize setup */
#ifdef PIXEL_ADDRESS
            dPRowInner = dPRowOuter + sizeof(PIXEL_TYPE);
#endif
#ifdef INTERP_Z
#  ifdef DEPTH_TYPE
            dZRowInner = dZRowOuter + sizeof(DEPTH_TYPE);
#  endif
            fdzInner = fdzOuter + span.zStep;
#endif
#ifdef INTERP_RGB
            fdrInner = fdrOuter + span.redStep;
            fdgInner = fdgOuter + span.greenStep;
            fdbInner = fdbOuter + span.blueStep;
#endif
#ifdef INTERP_ALPHA
            fdaInner = fdaOuter + span.alphaStep;
#endif
#ifdef INTERP_INDEX
            diInner = diOuter + span.indexStep;
#endif
#ifdef INTERP_INT_TEX
            dsInner = dsOuter + span.intTexStep[0];
            dtInner = dtOuter + span.intTexStep[1];
#endif
#ifdef INTERP_ATTRIBS
            dwInner = dwOuter + span.attrStepX[FRAG_ATTRIB_WPOS][3];
            ATTRIB_LOOP_BEGIN
               GLuint c;
               for (c = 0; c < 4; c++) {
                  daInner[attr][c] = daOuter[attr][c] + span.attrStepX[attr][c];
               }
            ATTRIB_LOOP_END
#endif

            while (lines > 0) {
               /* initialize the span interpolants to the leftmost value */
               /* ff = fixed-pt fragment */
               const GLint right = FixedToInt(fxRightEdge);
               span.x = FixedToInt(fxLeftEdge);
               if (right <= span.x)
                  span.end = 0;
               else
                  span.end = right - span.x;

#ifdef INTERP_Z
               span.z = zLeft;
#endif
#ifdef INTERP_RGB
               span.red = rLeft;
               span.green = gLeft;
               span.blue = bLeft;
#endif
#ifdef INTERP_ALPHA
               span.alpha = aLeft;
#endif
#ifdef INTERP_INDEX
               span.index = iLeft;
#endif
#ifdef INTERP_INT_TEX
               span.intTex[0] = sLeft;
               span.intTex[1] = tLeft;
#endif

#ifdef INTERP_ATTRIBS
               span.attrStart[FRAG_ATTRIB_WPOS][3] = wLeft;
               ATTRIB_LOOP_BEGIN
                  GLuint c;
                  for (c = 0; c < 4; c++) {
                     span.attrStart[attr][c] = attrLeft[attr][c];
                  }
               ATTRIB_LOOP_END
#endif

               /* This is where we actually generate fragments */
               /* XXX the test for span.y > 0 _shouldn't_ be needed but
                * it fixes a problem on 64-bit Opterons (bug 4842).
                */
               if (span.end > 0 && span.y >= 0) {
                  const GLint len = span.end - 1;
                  (void) len;
#ifdef INTERP_RGB
                  CLAMP_INTERPOLANT(red, redStep, len);
                  CLAMP_INTERPOLANT(green, greenStep, len);
                  CLAMP_INTERPOLANT(blue, blueStep, len);
#endif
#ifdef INTERP_ALPHA
                  CLAMP_INTERPOLANT(alpha, alphaStep, len);
#endif
#ifdef INTERP_INDEX
                  CLAMP_INTERPOLANT(index, indexStep, len);
#endif
                  {
                     RENDER_SPAN( span );
                  }
               }

               /*
                * Advance to the next scan line.  Compute the
                * new edge coordinates, and adjust the
                * pixel-center x coordinate so that it stays
                * on or inside the major edge.
                */
               span.y++;
               lines--;

               fxLeftEdge += fdxLeftEdge;
               fxRightEdge += fdxRightEdge;

               fError += fdError;
               if (fError >= 0) {
                  fError -= FIXED_ONE;

#ifdef PIXEL_ADDRESS
                  pRow = (PIXEL_TYPE *) ((GLubyte *) pRow + dPRowOuter);
#endif
#ifdef INTERP_Z
#  ifdef DEPTH_TYPE
                  zRow = (DEPTH_TYPE *) ((GLubyte *) zRow + dZRowOuter);
#  endif
                  zLeft += fdzOuter;
#endif
#ifdef INTERP_RGB
                  rLeft += fdrOuter;
                  gLeft += fdgOuter;
                  bLeft += fdbOuter;
#endif
#ifdef INTERP_ALPHA
                  aLeft += fdaOuter;
#endif
#ifdef INTERP_INDEX
                  iLeft += diOuter;
#endif
#ifdef INTERP_INT_TEX
                  sLeft += dsOuter;
                  tLeft += dtOuter;
#endif
#ifdef INTERP_ATTRIBS
                  wLeft += dwOuter;
                  ATTRIB_LOOP_BEGIN
                     GLuint c;
                     for (c = 0; c < 4; c++) {
                        attrLeft[attr][c] += daOuter[attr][c];
                     }
                  ATTRIB_LOOP_END
#endif
               }
               else {
#ifdef PIXEL_ADDRESS
                  pRow = (PIXEL_TYPE *) ((GLubyte *) pRow + dPRowInner);
#endif
#ifdef INTERP_Z
#  ifdef DEPTH_TYPE
                  zRow = (DEPTH_TYPE *) ((GLubyte *) zRow + dZRowInner);
#  endif
                  zLeft += fdzInner;
#endif
#ifdef INTERP_RGB
                  rLeft += fdrInner;
                  gLeft += fdgInner;
                  bLeft += fdbInner;
#endif
#ifdef INTERP_ALPHA
                  aLeft += fdaInner;
#endif
#ifdef INTERP_INDEX
                  iLeft += diInner;
#endif
#ifdef INTERP_INT_TEX
                  sLeft += dsInner;
                  tLeft += dtInner;
#endif
#ifdef INTERP_ATTRIBS
                  wLeft += dwInner;
                  ATTRIB_LOOP_BEGIN
                     GLuint c;
                     for (c = 0; c < 4; c++) {
                        attrLeft[attr][c] += daInner[attr][c];
                     }
                  ATTRIB_LOOP_END
#endif
               }
            } /*while lines>0*/

         } /* for subTriangle */

      }
   }
}

#undef SETUP_CODE
#undef RENDER_SPAN

#undef PIXEL_TYPE
#undef BYTES_PER_ROW
#undef PIXEL_ADDRESS
#undef DEPTH_TYPE

#undef INTERP_Z
#undef INTERP_RGB
#undef INTERP_ALPHA
#undef INTERP_INDEX
#undef INTERP_INT_TEX
#undef INTERP_ATTRIBS

#undef S_SCALE
#undef T_SCALE

#undef FixedToDepth

#undef NAME