Guys, I need a way to detect simple collision with walls. My map is pretty basic. All the floor is on the same height and I have very simple walls that I need to collide with.

Two ways come to mind and I'm wondering what's better.

1st - Put one camera watching my hero from above. Use this camera to render the depth values in front of the hero in another framebuffer. If the depth values in front of the hero are less than the depth value of some fragment from the hero, then there is a wall in front of him.

OR

2nd. Make AABBs for every wall. The problem with this is that every time there is a turn, I need to divide the wall into separate meshes and find the AABB for that mesh, because if the wall is like this:

(top view)

____

| |

___ | |

|_______ |

And I count these two rectangles as one mesh and find the min and max x,y,z of the two figures, the AABB is going to be this:

(top view)

________

| |

| |

|______ _|

And this is very inaccurate. That's why I have to make a new mesh every time the wall turns left or right.

What to choose?

I hope someone understood something from this very bad explanation. :lol:

If the reason you can't use an AABB for your walls is that the walls have corners in them - i.e. they are concave objects - you could split those walls into 2 convex walls, each with its own AABB.

And what do you think about the first option?

Sounds wrong to use the camera and the depth buffer to query for information that is surely already in the game engine.

Depending on your game design, you might be able to use a navigation mesh:

https://en.wikipedia.org/wiki/Navigation_mesh

This can greatly simplify and accelerate your collision detection, and allow path finding too.

Guys, thanks a lot for getting me started. Will post later if there is some progress.

Yes, I was about to say that if it's axis aligned and regular in shape an array would probably work.