*Bounty: 50*

*Bounty: 50*

There is a popular paper, and numerous examples, on how to efficiently perform collision detection for a line with a grid. However, I’m drawing up blanks on how to do the same thing but with a line that has thickness.

In my game, I’m considering adding projectiles that are not infinitly thin (for example, a giant plasma ball launcher), and I need to figure out which cells along a grid that it collides with. Initially I thought it’d be as simple as just using the Minkowski Sum method of adding the width/height of the projectile to each cell of the grid, and then treating the projectile as infinity thin line along a bloated-overlapping-grid, but that doesn’t look like it’s going to work with the existing algorithm.

Are there any other papers/algorithms that describe how to accomplish this? Or is there a way to modify the existing algorithm to accomplish this? Or are there any tricks to implementing this indirectly?