iOS Can't get alpha blended textures to behave properly...

[cwolves]

I can't for the life of me get two png textures to render on top of one-another properly when the top one has partial transparency.

The above image shows three renders. One using polygons (a blue square with a white diamond and 50% opacity on top of it, blending mode: glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA))

And two with textures. One using the "normal" rendering mode, the other using the "premultiplied" rendering mode, at least according to forums...

All I want is to reproduce the first result using textures....


Oh, and I've LITERALLY tried every blending mode possible with glBlendFunc.

 

[lazydog]

Stupid question, but have you enabled blending?

glEnable( GL_BLEND ) ;

Oh and also what texture mode are you using? I use white polygons with the modulate mode:-

glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE ) ;

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