Using the same rendering code as when I render to the screen, I get outlines around my quad’s and tri’s. The outlines are the same color as the baclkground clear color. It would seem there’s a state that I’m missing but I can’t find it. How do I get rid of these outlines?
I discovered its the blending:
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
Turning it off removes the borders but of course I lose any transparency. So why dows it work to the screen but not a bitmap?
Just a guess, have you got polygon smooth mode on?
You got it. It was the combo of Polygon Smoothing and setting
glHint ( GL_LINE_SMOOTH_HINT , GL_NICEST ) ;
glHint ( GL_POLYGON_SMOOTH_HINT , GL_NICEST ) ;