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This has to do with collision detection between a ray and a cube. I have a camera position that I am looking from and a ray is being shot into the scene which contains a cube.

I have the ray starting position and direction in 3D space. The cube is defined by its center position coordinates along with height, width, and depth.

I am following an algorithm I found online, and a task that I have become stuck on is finding the closest and farthest points of the cube. Google searches haven't proved promising for me thus far, I would appreciate any suggestions!

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The farthest point on the cube has to be a vertex, so that part is easy. (In general, the farthest point in any closed convex set has to be on its boundary - just check that it's true on any line segment - and all the faces and edges of the cube are also convex.) –  Greg Martin Feb 28 '12 at 0:18
Yes, I believe you are right. I wasn't quite sure before but this certainly makes intuitive sense. –  Aaron Feb 28 '12 at 0:46
To clarify the question, do you mean the closest and farthest points on a fixed ray? Or do you mean the closest and farthest points on any ray from a fixed point? –  Code-Guru Jul 19 '12 at 14:47

1 Answer 1

Do you mean the longest distance of a ray drawn inside of the cube? If yes, then you need to draw the ray from one vertex to the other side in that way it forms a triangle with two diagonals of the square faces and the height will be the side of square face.

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