Tagged Questions

7
votes
3answers
334 views

Narrow-phase collision detection algorithms

There are three phases of collision detection. Broadphase: It loops between all objecs that can interact, false positives are allowed, if it would speed up the loop. Narrowphase: Determines whether ...
6
votes
1answer
558 views

Why doesn't Unity's OnCollisionEnter give me surface normals, and what's the most reliable way to get them?

Unity's on collision event gives you a Collision object that gives you some information about the collision that happened (including a list of ContactPoints with hit normals). But what you don't get ...
1
vote
2answers
1k views

How to handle 3D collisions using raycasting (with a reflection vector?)

I'm making a game using THREE.JS, and I want my character to walk on the terrain, and collide with static 3D objects (=AABB boxes) that are on that terrain. The problem is: THREE.JS has only a ...
1
vote
1answer
823 views

Raycasting Collision Detection

I need to check for collisions when firing a bullet, but I have a few questions first. My game is 2D and tile based, it also uses the XNA framework. From what I've read raycasting or continuous ...
4
votes
1answer
484 views

Finding if a point is inside of a mesh (Point-in-polyhedron)

How can I find if a point (Vector3) is inside of a mesh? Would this work for both concave and convex objects? I read somewhere that if you raycast in both directions of every axis (X, -X, Y, -Y, Z, ...
0
votes
2answers
493 views

3D collision detection with meshes using only raycasting?

I'm building a game using WebGL and Three.js, and so far I have a terrain with a guy walking on it. I simply cast a ray downwards to know the terrain height. How can I do this for other 3D objects, ...
3
votes
2answers
319 views

What are the technologies that makes physics engines so good for raycasting?

again. This question is strictly related to this one so, what is the technology that makes physics engines suitable for raycasting? It is a particular data structure? Has it to do with the engine's ...
4
votes
3answers
2k views

Why do we use physics engines for collision testing or raycasting?

There is a thing I don't understand about game engines: why it is so common to use physics engines to do raycasting or collision testing? Say that you have a 3D scene loaded in your scene manager ...