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LibGDX Box2d Collision Error

I'm aware this is going to be somewhat vague. I'm writing an action adventure style game and I'm having a random (as in seemingly spontaneous) issue where the body I'm using for the character is getting caught on nothing. I'm not actually handling collisions, I'm just using the built in body touches body causes collision feature. The debug renderer indicates that there is a collision when there shouldn't be one and I can't discern why it would happen. What I suppose I need is someone more familiar with LibGDX than I am to surmise why this would happen. Player is stuck on the left

Solution

  • I guess @CoderMusgrove is right.
    If you have a flat floor, created out of many boxes, you might get stuck on the edges of them.
    Thats because in the physics simulation, the body will be pushed down by gravity. This results in a collision, which usualy pushes the body back up.
    But if you get pushed down in between two boxes, the collision resolver sometimes decides to push you back, as this is the shorter way out of the collision.
    You can read more about this here.
    Also the solutions are discussed in the link. There are a few different ways:
    - Cutting the edges: If you cut the edges of your character, the collision resolver will more likely decide to push your character up. I tryed this solution to, but in my case it slowed down the character a bit. Also when i cut the edges to much, the character started jumping every time he moved onto another box.
    - Using edge-shapes: Instead of using boxes, you could just use edges. It seems like you don't get stuck on edges that often, so that might allready solve your issue.
    - Use gost vertices: Using Ghost Vertices, you can give the resolver a hint on how to resolve the colission. Those ghost vertices are used for collision response only, so they won't affect the rest of the simmulation.
    - Combining boxes: The best solution would be to create one big box out of all adjacent boxes, if possible. This would solve the problem, as there are no more edges where the body could get stuck.