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iPick12
12-30-2012, 07:09 AM
Hello,

So, I've been trying to do this for the past few days:
I need to render a GL_POLYGON with it's content masked.
glPolygonStipple() is exactly the function I need but unfortunately it's not supported anymore.
Please note that I want to be able to change the color of the solid areas, so that I can load the pattern from a file but change it's color dynamically.
I'm almost sure that the solution has to do with textures but I don't know exactly what to do.

Thanks in advance,
Jason

I hope that I describe my problem correctly.

V-man
12-30-2012, 01:22 PM
You can stick with GL 1.1 to 2.1 if you really want that function.
If you want to use modern GL, then you can use a texture that an alpha value or some specific value in the RGB layer. In your fragment shader, you just need to kill the fragment with the discard command.



if(texture.a==0.0)
discard;

etc etc.