In my particle system engine that i''m creating, I use TGA files for the particle textures. I would like to know how to use the alpha channel in my textures. For instance, if I am using a basic solid circle for one of my particles, how do i set photoshop up so that when I load the TGA in my particle system only the circle will show and not the background stuff? Thank you.

Alpha == 1 : 100% opaque
Alpha == 0 : 100% transparent (no color)

How to setup photoshop : I don''t know, I don''t have photoshop. Find a way to convert whatever format the data has in memory to RGBA before saving. If you''re writing the TGA loader yourself, knowing the specs may help.