Hi guys, I'm very new to PD and GEM, but started playing around with it. One thing I want to do is to experiment with different blend effects. Playing around with alpha is relatively easy, but I want more sophisticated blending like multiply and screen. Has anyone tried to do this? I tried calling an OpenGL function, GEMglBlendFunc by attaching it to gemhead but nothing happened. I called GEMglEnable with the right GLdefiine as well. I don't have the patch file on me right now, but I'll try to upload it once I get hold of it. If anyone has a sample patch that can show me how to do this, that would be great.

By the way, I know that it's possible to do this using the pix_ objects, i.e. pix_multiply, etc. But I want to apply the effect to the whole schene with 3D objects that are moving.

If everything fails, I think I'll have to learn a bit more of OpenGL and maybe try it in C++ first and then translate it into pd.