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Dakeyras
07-20-2005, 02:54 AM
I have an RGBA textured object which I perform an alpha test on. It works fine in normal render, but in selection render, the masked-out parts are still selectable. So my questions are:

1. Is the alpha test performed when in selection mode? I know the Red Book says "In RGBA mode, ..." but that's referring to RGBA versus indexed?

2. Are textures (and thus the alpha channel) processed in selection mode?

3. Any other possible reason why the above problem is happening?

Relic
07-20-2005, 04:38 AM
1. + 2.) No, there is no rasterization done at all.
3.) Selection mode uses only the geometry information. Read the manual on glSelectBuffer.

Dakeyras
07-20-2005, 05:08 PM
Thanks for replying. So if I want to process the alpha mask the only solution is to implement the picking myself?