- case GL_ADD: /* GL_EXT_texture_add_env */
- switch (format) {
- case GL_ALPHA:
- for (i=0;i<n;i++) {
- /* Rv = Rf */
- /* Gv = Gf */
- /* Bv = Bf */
- rgba[i][ACOMP] = CHAN_PRODUCT(rgba[i][ACOMP], texel[i][ACOMP]);
- }
- break;
- case GL_LUMINANCE:
- for (i=0;i<n;i++) {
- ChanTemp Lt = texel[i][RCOMP];
- ChanTemp r = rgba[i][RCOMP] + Lt;
- ChanTemp g = rgba[i][GCOMP] + Lt;
- ChanTemp b = rgba[i][BCOMP] + Lt;
- rgba[i][RCOMP] = MIN2(r, CHAN_MAX);
- rgba[i][GCOMP] = MIN2(g, CHAN_MAX);
- rgba[i][BCOMP] = MIN2(b, CHAN_MAX);
- /* Av = Af */
- }
- break;
- case GL_LUMINANCE_ALPHA:
- for (i=0;i<n;i++) {
- ChanTemp Lt = texel[i][RCOMP];
- ChanTemp r = rgba[i][RCOMP] + Lt;
- ChanTemp g = rgba[i][GCOMP] + Lt;
- ChanTemp b = rgba[i][BCOMP] + Lt;
- rgba[i][RCOMP] = MIN2(r, CHAN_MAX);
- rgba[i][GCOMP] = MIN2(g, CHAN_MAX);
- rgba[i][BCOMP] = MIN2(b, CHAN_MAX);
- rgba[i][ACOMP] = CHAN_PRODUCT(rgba[i][ACOMP], texel[i][ACOMP]);
- }
- break;
- case GL_INTENSITY:
- for (i=0;i<n;i++) {
- GLchan It = texel[i][RCOMP];
- ChanTemp r = rgba[i][RCOMP] + It;
- ChanTemp g = rgba[i][GCOMP] + It;
- ChanTemp b = rgba[i][BCOMP] + It;
- ChanTemp a = rgba[i][ACOMP] + It;
- rgba[i][RCOMP] = MIN2(r, CHAN_MAX);
- rgba[i][GCOMP] = MIN2(g, CHAN_MAX);
- rgba[i][BCOMP] = MIN2(b, CHAN_MAX);
- rgba[i][ACOMP] = MIN2(a, CHAN_MAX);
- }
- break;
- case GL_RGB:
- for (i=0;i<n;i++) {
- ChanTemp r = rgba[i][RCOMP] + texel[i][RCOMP];
- ChanTemp g = rgba[i][GCOMP] + texel[i][GCOMP];
- ChanTemp b = rgba[i][BCOMP] + texel[i][BCOMP];
- rgba[i][RCOMP] = MIN2(r, CHAN_MAX);
- rgba[i][GCOMP] = MIN2(g, CHAN_MAX);
- rgba[i][BCOMP] = MIN2(b, CHAN_MAX);
- /* Av = Af */
- }
- break;
- case GL_RGBA:
- for (i=0;i<n;i++) {
- ChanTemp r = rgba[i][RCOMP] + texel[i][RCOMP];
- ChanTemp g = rgba[i][GCOMP] + texel[i][GCOMP];
- ChanTemp b = rgba[i][BCOMP] + texel[i][BCOMP];
- rgba[i][RCOMP] = MIN2(r, CHAN_MAX);
- rgba[i][GCOMP] = MIN2(g, CHAN_MAX);
- rgba[i][BCOMP] = MIN2(b, CHAN_MAX);
- rgba[i][ACOMP] = CHAN_PRODUCT(rgba[i][ACOMP], texel[i][ACOMP]);