- GLfloat rscale = 1.0F / CHAN_MAXF;
- GLfloat gscale = 1.0F / CHAN_MAXF;
- GLfloat bscale = 1.0F / CHAN_MAXF;
- GLfloat ascale = 1.0F / CHAN_MAXF;
- GLuint i;
-
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLint Rs, Gs, Bs, As; /* Source colors */
- GLint Rd, Gd, Bd, Ad; /* Dest colors */
- GLfloat sR, sG, sB, sA; /* Source scaling */
- GLfloat dR, dG, dB, dA; /* Dest scaling */
- GLfloat r, g, b, a;
-
- /* Source Color */
- Rs = rgba[i][RCOMP];
- Gs = rgba[i][GCOMP];
- Bs = rgba[i][BCOMP];
- As = rgba[i][ACOMP];
-
- /* Frame buffer color */
- Rd = dest[i][RCOMP];
- Gd = dest[i][GCOMP];
- Bd = dest[i][BCOMP];
- Ad = dest[i][ACOMP];
-
- /* Source RGB factor */
- switch (ctx->Color.BlendSrcRGB) {
- case GL_ZERO:
- sR = sG = sB = 0.0F;
- break;
- case GL_ONE:
- sR = sG = sB = 1.0F;
- break;
- case GL_DST_COLOR:
- sR = (GLfloat) Rd * rscale;
- sG = (GLfloat) Gd * gscale;
- sB = (GLfloat) Bd * bscale;
- break;
- case GL_ONE_MINUS_DST_COLOR:
- sR = 1.0F - (GLfloat) Rd * rscale;
- sG = 1.0F - (GLfloat) Gd * gscale;
- sB = 1.0F - (GLfloat) Bd * bscale;
- break;
- case GL_SRC_ALPHA:
- sR = sG = sB = (GLfloat) As * ascale;
- break;
- case GL_ONE_MINUS_SRC_ALPHA:
- sR = sG = sB = (GLfloat) 1.0F - (GLfloat) As * ascale;
- break;
- case GL_DST_ALPHA:
- sR = sG = sB = (GLfloat) Ad * ascale;
- break;
- case GL_ONE_MINUS_DST_ALPHA:
- sR = sG = sB = 1.0F - (GLfloat) Ad * ascale;
- break;
- case GL_SRC_ALPHA_SATURATE:
- if (As < CHAN_MAX - Ad) {
- sR = sG = sB = (GLfloat) As * ascale;
- }
- else {
- sR = sG = sB = 1.0F - (GLfloat) Ad * ascale;
- }
- break;
- case GL_CONSTANT_COLOR:
- sR = ctx->Color.BlendColor[0];
- sG = ctx->Color.BlendColor[1];
- sB = ctx->Color.BlendColor[2];
- break;
- case GL_ONE_MINUS_CONSTANT_COLOR:
- sR = 1.0F - ctx->Color.BlendColor[0];
- sG = 1.0F - ctx->Color.BlendColor[1];
- sB = 1.0F - ctx->Color.BlendColor[2];
- break;
- case GL_CONSTANT_ALPHA:
- sR = sG = sB = ctx->Color.BlendColor[3];
- break;
- case GL_ONE_MINUS_CONSTANT_ALPHA:
- sR = sG = sB = 1.0F - ctx->Color.BlendColor[3];
- break;
- default:
- /* this should never happen */
- gl_problem(ctx, "Bad blend source RGB factor in do_blend");
- return;
- }
-
- /* Source Alpha factor */
- switch (ctx->Color.BlendSrcA) {
- case GL_ZERO:
- sA = 0.0F;
- break;
- case GL_ONE:
- sA = 1.0F;
- break;
- case GL_DST_COLOR:
- sA = (GLfloat) Ad * ascale;
- break;
- case GL_ONE_MINUS_DST_COLOR:
- sA = 1.0F - (GLfloat) Ad * ascale;
- break;
- case GL_SRC_ALPHA:
- sA = (GLfloat) As * ascale;
- break;
- case GL_ONE_MINUS_SRC_ALPHA:
- sA = (GLfloat) 1.0F - (GLfloat) As * ascale;
- break;
- case GL_DST_ALPHA:
- sA =(GLfloat) Ad * ascale;
- break;
- case GL_ONE_MINUS_DST_ALPHA:
- sA = 1.0F - (GLfloat) Ad * ascale;
- break;
- case GL_SRC_ALPHA_SATURATE:
- sA = 1.0;
- break;
- case GL_CONSTANT_COLOR:
- sA = ctx->Color.BlendColor[3];
- break;
- case GL_ONE_MINUS_CONSTANT_COLOR:
- sA = 1.0F - ctx->Color.BlendColor[3];
- break;
- case GL_CONSTANT_ALPHA:
- sA = ctx->Color.BlendColor[3];
- break;
- case GL_ONE_MINUS_CONSTANT_ALPHA:
- sA = 1.0F - ctx->Color.BlendColor[3];
- break;
- default:
- /* this should never happen */
- sA = 0.0F;
- gl_problem(ctx, "Bad blend source A factor in do_blend");
- }
-
- /* Dest RGB factor */
- switch (ctx->Color.BlendDstRGB) {
- case GL_ZERO:
- dR = dG = dB = 0.0F;
- break;
- case GL_ONE:
- dR = dG = dB = 1.0F;
- break;
- case GL_SRC_COLOR:
- dR = (GLfloat) Rs * rscale;
- dG = (GLfloat) Gs * gscale;
- dB = (GLfloat) Bs * bscale;
- break;
- case GL_ONE_MINUS_SRC_COLOR:
- dR = 1.0F - (GLfloat) Rs * rscale;
- dG = 1.0F - (GLfloat) Gs * gscale;
- dB = 1.0F - (GLfloat) Bs * bscale;
- break;
- case GL_SRC_ALPHA:
- dR = dG = dB = (GLfloat) As * ascale;
- break;
- case GL_ONE_MINUS_SRC_ALPHA:
- dR = dG = dB = (GLfloat) 1.0F - (GLfloat) As * ascale;
- break;
- case GL_DST_ALPHA:
- dR = dG = dB = (GLfloat) Ad * ascale;
- break;
- case GL_ONE_MINUS_DST_ALPHA:
- dR = dG = dB = 1.0F - (GLfloat) Ad * ascale;
- break;
- case GL_CONSTANT_COLOR:
- dR = ctx->Color.BlendColor[0];
- dG = ctx->Color.BlendColor[1];
- dB = ctx->Color.BlendColor[2];
- break;
- case GL_ONE_MINUS_CONSTANT_COLOR:
- dR = 1.0F - ctx->Color.BlendColor[0];
- dG = 1.0F - ctx->Color.BlendColor[1];
- dB = 1.0F - ctx->Color.BlendColor[2];
- break;
- case GL_CONSTANT_ALPHA:
- dR = dG = dB = ctx->Color.BlendColor[3];
- break;
- case GL_ONE_MINUS_CONSTANT_ALPHA:
- dR = dG = dB = 1.0F - ctx->Color.BlendColor[3] * ascale;
- break;
- default:
- /* this should never happen */
- dR = dG = dB = 0.0F;
- gl_problem(ctx, "Bad blend dest RGB factor in do_blend");
- }