   Convex hulls in modern games
Does Unity and other modern games still use convex hulls? Or do they check for collisions with polys? What about Doom III and Rage? Don't they somehow separate the collision model from the rendered polys?
  I would say most modern engines collide on polygon level, but use various detaillevel of collision geometry. thats why you can buy objects with ccollision proxies in the unity asset store   ;I think most modern games will use the simplest representation they can get away with for physics. That means there will almost always be a separation between collision mesh and render mesh. They will often use convex hulls or a couple of convex hulls attached to represent objects, or even simple geometric shapes like boxes, spheres and cylinders when they can get away with it. Typically for environments it'll be a polygon soup, but lower detail than the render mesh.For objects/characters in order of preference it'll be geometric shapes, single convex hulls, multiple convex hulls, then quite rarely, non-convex polygonal shapes.;Unreal development network - Collision reference.  Scroll down to show zeroextent .Hulls are still there and kicking.;Yeah, they're used all the time, as are simpler things like spheres and AABBs.  A game usually does some sort of tiered check, something like Given a pointIs it within the collision sphere?Is it within the convex hull?Is it hitting a polygon on the model (and sometimes this is a separate collision mesh) And some games do less than that, Mechwarrior Online, for example, the models are represented by a series of boxes.  (As are many shooters) And that's also skipping another check, which might be, checking only objects that are in the same node of the octree or some other culling / grouping method.;Tri-mesh vs Tri-mesh is a very complex operation, so typically you might find that an environment is represented as a tri-mesh, but then the objects in that environment are simplified (spheres, boxes, convex shapes, etc).;I think the vast majority of people use compound primitive shapes or convex hull, depending. Compound shape is probably more useful in many cases.