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Hello, 1. These Bounding Volumes are colliding but the objects don't. How can i test collision after Bounding Volume collision? Please at least give me the Algorithm name so i could Google it and find some information needed. 2. How can i find the point of collision? (For Physics) 3. Which values needed for Physical Contact? Thanks, Kasya

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The Separating Axis Theorem is the standard method for determining collision. Your shapes are pretty odd though, and might not work well for that. Are those accurate depictions of the shapes in your game? Perhaps you're looking for pixel-perfect collision? (This method is meant for bitmaps, where you can simply see if any of their non-transparent pixels are overlapping.)

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Oh really sorry, I forget to tell. I am working on 3D Engine. I can't draw that pic in 3D. Because of that i drew it in 2D. LoL. In 3D how to determine if 2 points of objects are colliding. Or 2 polygons are colliding if it is possible.

Thanks,
Kasya

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Generally, you have to first convert your object into a collection of convex polyhedra. Then you can do point-plane penetration checks from one object into the planes that make up the polyhedra or the other. This is quite expensive so a bounding volume check is a good thing to do first.

The other way is to approximate your object as a collection of easy to use bounding volumes (typically, cuboids, cylinders or spheres), which won't give you an exact collision but it will be close enough for rapid action games, particularly in 3D where you usually can't see the angle from which the collision is wrong.

• ### What is your GameDev Story?

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