PolygonStipple

I’m having hard time finding some papers, documents, tutorials on this one. How can glPolygonStipple be used to do screen door effect? From what I remember, this can be used to give a transparent look. It would be a total replacement to the glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA) issue.

I know there are other solutions such as OIT, but I am looking for something simple for GL 1.1

I don’t think you can use polygon stipple as a complete replacement for blending. The stipple is screen-space aligned, so one blended object on top of another will simply look like the last one you drew. You can’t do order-independent transparency with stipple.

How far back does CSAA reach (1.3?). By far the easiest way to fly for dense veggies but dunno about 1.1.

Think again, search here for “stipple” :
http://www.opengl.org/resources/code/samples/glut_examples/examples/examples.html

And it has modern uses too, as described by this interesting paper :
http://graphics.cs.uiuc.edu/~kircher/inferred/inferred_lighting_paper.pdf

Think again, search here for “stipple” :

That’s because they drew each object with a different stipple pattern. So you could use it if you have a limited number of objects and draw each one with a different pattern. But for stipple-based transparency, you generally want the pattern to be the effective blend value for that object: dense patterns mean more opaque, and sparse patterns mean more transparent.

This is not not a general solution for OIT.

Yeah but for “something simple for GL 1.1” there is not a lot of general (and realtime) options …

Thanks, it has been a long time since I’ve seen that examples page. Like I suspected, they use different patterns and it is nice to have that tables of bitpatterns that they have in the source.