April 05
Prof. Ismael H. F. Santos -  ismael@tecgraf.puc-rio.br                                                          2
Especificação dos fatores
glBlendFunc (fator_frag, fator_pixel);
GL_ZERO src or dst (0,0,0,0)
GL_ONE src or dst (1,1,1,1)
GL_DST_COLOR src (Rd,Gd,Bd,Ad)
GL_SRC_COLOR dst (Rs,Gs,Bs,As)
GL_ONE_MINUS_DST_COLOR src (1,1,1,1) - (Rd,Gd,Bd,Ad)
GL_ONE_MINUS_SRC_COLOR dst (1,1,1,1) - (Rs,Gs,Bs,As)
GL_SRC_ALPHA src or dst (As,As,As,As)
GL_ONE_MINUS_SRC_ALPHA src or dst (1,1,1,1) - (As,As,As,As)
GL_DST_ALPHA src or dst (Ad,Ad,Ad,Ad)
GL_ONE_MINUS_DST_ALPHA src or dst (1,1,1,1) - (Ad,Ad,Ad,Ad)
GL_SRC_ALPHA_SATURATE src (f ,f ,f ,1); f = min(As,1-Ad)