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Index › Programming Questions & Help › OpenGL and 3D Libraries › openGL blend modes - A strange gift for you
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openGL blend modes - A strange gift for you (Read 3338 times)
ness
openGL blend modes - A strange gift for you
Apr 8th, 2008, 6:11pm  
To make it easier to grasp the combinations of different openGL blend modes I quickly ammended the built-in example called "SpaceJunk" with some neat functionality.

You can cycle through the blend modes for each variable in the function Code:
glBlendFunc( X1, X2 )
You can also toggle depth testing on and off.

The keys are:
Code:

'e': X1 = next openGL blend mode
'd': X1 = previous openGL blend mode
'r': X1 = next openGL blend mode
'f': X1 = previous openGL blend mode
'z': toggle depth testing (disabled by default)


you may notice a blank window at first. just change one of the blend variables to see something cool.

the code is too long for a post so i placed it here:
http://boxofbooze.com/processing/glblend.html

for more information on openGL blend modes see this helpful webpage:
http://pyopengl.sourceforge.net/documentation/manual/glBlendFunc.3G.html

feel free to correct anything that is wrong or missing.
--ness
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pyramind
Re: openGL blend modes - A strange gift for you
Reply #1 - Apr 9th, 2008, 6:55am  
This is very helpful ness, thank you!
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http://www.earslap.com
 
ness
Re: openGL blend modes - A strange gift for you
Reply #2 - Apr 9th, 2008, 11:23pm  
Just letting everyone know that I had found a few errors and fixed them. The link above has the corrected code.
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wayfarer_boy
Re: openGL blend modes - A strange gift for you
Reply #3 - Oct 29th, 2008, 4:58pm  
I know this is an old post, but it's massively useful for a practical introduction to glBlendFunc, and really helped me get my head around it.  Thanks a lot Smiley
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claudiomidolo
Re: openGL blend modes - A strange gift for you
Reply #4 - Nov 20th, 2008, 2:54am  
This is great! it really helped me a lot to experiment with blending modes!

I added some functionalities to it you can read about it here:

http://claudiodt.blogspot.com/2008/11/opengl-blending-modes-processing-test.html

or directly check the application here:

http://de.posi.to/codici/openGLblendmodesTest/
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