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OpenGL Transparent pixels

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musicon    110
This is quite an advanced XNA topic hence its going here not in Beginners forum. While I can do most standard things in xna (and to a point directx and opengl) I am stumped on the process of finding transparent pixels in an image (for collision detection purposes). I am in need of some simple tutorials somewhere on the web or even a book that explains this properly. Riemers does this in the cannongame tutorial but it feels like running before walking, even with a good knowledge of all the stuff up to that point in that game.

So if you have seen a useful explanation (such as setting colors to 2d array in the first place) please post a link.

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xbattlestation    466
There are some great tutorials on the app hub for collision detection:


Sounds like you want the 2d perpixel tutorial, or if you are rotating & resizing your sprites, the 2d perpixel transformed.

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