Rendering effects with transparency.

[RogerGMartins]

I'm not able to render effects, for example text, with a transparent background, is this designed by choice, or is there any problem?

[quadbyte]

I'm having the same issue. I tried tweaking the different ofClear / glClear call "here and there" but without much luck. Would love to get your insight on this Neil. Thanks

[neilmendoza]

Unfortunately, it will require a bit of work to get transparency to work properly, clearing the framebuffer to transparent is one part of it. Another problem though is that if you look at the XXXXPass.cpp files, most of the shaders just set the alpha value to 1.0. Some effects, such as bloom also interact with the blending mode.

Hopefully I'll get some time at some point to update the addon a little. There's a few things I'd like to add such as a background colour to clear the FBs to (that would address this issue), ofParameter support and ofGLProgrammableRenderer support. If anyone fancies helping out get in touch...

[chemabc]

Hi, Neil, I really would like to help you with the transparency issue. It would be very useful for a urgent project I am finishing. If I could use ofxPostProcessing that would be great. I am not the biggest expert in shaders but I understand and manipulate the basics, also about pingpong. If you can point me in the right direction, I think I can start digging to solve it asap. What do you think? First thing, I guess, is making FBOS with GL_RGBA, if ofFbo::settings?