[SDL] glSDL and Accelerated Alpha Blending

[David Ludwig]

Hello!

Does anyone here know if it is possible to do hardware accelerated image 
blending using glSDL?  In particular, I am trying to overlay a set of 
images w/ alpha channels onto a transparent surface.  The general idea 
is that I could do some off-screen compositing, and then blit the result 
to the screen as if each individual image were directly blitted to the 
screen.  I've been able to do this in software, however things are 
starting to get slow and I was hoping to offload this work onto the 
user's gfx card.

It's my understanding that SDL does not directly support alpha belnding, 
whereby the destination image's alpha channel is modified.  What I was 
hoping is that there was a way, perhaps using glSDL, to hack this 
feature in.

Take care!

--
David Ludwig
davidl at funkitron.com
http://www.funkitron.com







Does anyone here know if it is possible to do hardware-accelerated alpha 
blending via SDL?  In particular, I'm looking to overlay two images with 
alpha channels onto a transparent surface, and then draw that to the 
screen.  It's my understanding that SDL  does not support this case, 
however using SDL + OpenGL does.  What I'm hoping to avoid is