LÖVE

Thanks for having a look A few followup questions.

First, are you sure this is the case? The reason I'm asking is because when I collide with the ceiling just jumping straight up into it my yvel is set to 0 and I immediately fall.

Second, if you're right and this is what's causing the problem does this mean that setting the y velocity to 0 is not the proper action to take when colliding with something from below?

Thanks again for responding

I'm fairly certain this is the case, but I can't be sure. I'll look around more when I get some time.

I haven't looked at the source, but if you are going up and hit your head you should set the y velocity to zero *if it's greater than zero, not if it's less'. Otherwise gravity won't be able to make you fall, as you keep negating it's effect by killing vertical velocity - you want to kill upward velocity only.