How to find all the cubes that the ray intersects in a 3d mesh?

Question

I need to cast a beam from the earth into the sun and want to find if the object is in the shade. I plan to do this by tracing the line from the cube of the earth to the sun and finding that an object is interfering. However, I am not familiar with math to find all the cubes that the line intersects, so that I can check if they are full. Can anyone shed some light on this?

Answer 1

Brute force method - checking each cube on your line. There was some kind of non-trivial IIRC geometry.

Oh. Googling "clash with the cube of the line" attracted a lot of hits. It looks pretty promising.

http://www.devmaster.net/forums/archive/index.php/t-371.html

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http://www.gamedev.net/community/forums/topic.asp?topic_id=185204

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Answer 2

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