OpenGl Compositing Graphics

How is compositing graphics achieved in OpenGl in Xojo? Please could somebody link me to some documentation like this: http://docs.oracle.com/javase/tutorial/2d/advanced/compositing.html? I have googled it but cannot find anything. I am not asking you to search through more pages on google, just so you do not think I am being too lazy. But I think somebody who knows more keywords for compositing graphics than me could find this better. Thanks.

I think what you want is the blending options. Turn on blending with

OpenGL.glEnable(OpenGL.GL_BLEND)

then set one of the many options

OpenGL.glBlendFunc(OpenGL. GL_ONE_MINUS_SRC_COLOR, OpenGL. GL_ONE)

there’s also glBlendEquation and glBlendFuncSeparate that can modify blending, I forget exactly how these all interact.

http://www.opengl.org/sdk/docs/man/xhtml/glBlendFunc.xml
http://www.glprogramming.com/red/chapter06.html#name1

[quote=37068:@stuart s]I think what you want is the blending options. Turn on blending with

OpenGL.glEnable(OpenGL.GL_BLEND)

then set one of the many options

OpenGL.glBlendFunc(OpenGL. GL_ONE_MINUS_SRC_COLOR, OpenGL. GL_ONE)

there’s also glBlendEquation and glBlendFuncSeparate that can modify blending, I forget exactly how these all interact.

http://www.opengl.org/sdk/docs/man/xhtml/glBlendFunc.xml
http://www.glprogramming.com/red/chapter06.html#name1[/quote]
Thankyou. Very helpful.