Calculating 2D (screen) coordinates from 3D positions in XNA 4.0

Posted by NDraskovic on Game Development See other posts from Game Development or by NDraskovic
Published on 2012-07-11T09:27:39Z Indexed on 2012/07/11 15:24 UTC
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collision-detection

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xna-4.0

I have a program that draws some items to the scene by loading their positions from a file. Now I want to place a Ray on the same location where the items are drawn. So my question is how can I calculate the position of the ray (it's 2D components) by using 3D coordinates of each particular item? The items don't move anywhere, so once they are placed they stay until the end of the programs execution. Thanks.

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