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B4

OpenGL Transparency in OpenGL

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Hi, I had some questions about transparency in OpenGL. I know that you need to load the textures in RGBA mode, and use glBlend() to make the transparent, but I do not understand how to actually set part of an image transparent in a paint program. For example, if I wanted all red to be transparent, how would I set this in Photoshop? And after setting this, does OpenGL not show the transparent colors? Thanks. -B4

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Well, the way I do transparency (it may not be the best ) is by turning on alpha with this function: glBlendFunc(GL_SRC_ALPHA,GL_SRC_COLOR);

Then, in Paint Shop Pro 7.0 I can create create an alpha map by doing this (you''ll have to figure this out for Photoshop, I know they''re different):

Masks->New->Show All
Masks->Edit (Check On)
*Draw The Mask*
Masks->Edit (Check Off)
Masks->Save to Alpha Channel
Then save in 24-bit uncompressed TGA format .



http://www.gdarchive.net/druidgames/

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i think null and void meant 32bit instaed of 24bit.

in photoshop go to the dialog with layers/channels/paths at the top click below on the create new channel button and bobs your uncle the newq channel is the alpha channel

http://members.xoom.com/myBollux

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