
Sven Panne wrote:
I am not completely sure, but it looks like the binding groups the enabling of basic blending and the specification of extended blending equations together. So that if you wanted to enable blending, you would do
blendEquation $= Just FuncAdd
and calling
blendEquation $= Nothing
to disable it.
Yep, that's correct. If setting part of the OpenGL state is cheap (like glBlendEquation), the Haskell binding combines this with the corresponding glEnable/glDisable call using the Maybe type. This is much cleaner IMHO and normally doesn't have any measurable performance impact. If it does, you should better take some care to minimize state changes, anyway... :-)
Does this rely upon the underlying OpenGL implementation/driver
supporting glBlendEquation() (i.e. OpenGL 1.3 or 1.2+GL_ARB_imaging)?
--
Glynn Clements