Easy to get stuck on the ceiling when colliding with a shape while jumping

[parasyte]

Here's a map that has this problem... Just jump against the spikes (they are rendered incorrectly, see #754)

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[parasyte]

This is just a platformer bug.

melonJS/examples/platformer/js/entities/player.js

Line 158 in bbc06f8

this.body.vel.y -= this.body.maxVel.y * me.timer.tick;

Make this line conditional (based on collision depth) to fix it... Only jump if player collides with the entity by falling on it.

[parasyte]

Thinking on this one some more, seems like the best thing would be to jump if the player is falling (and hits the top), or switch to falling at terminal velocity if the player is jumping (and hits the bottom).

AFAICT, that should cover all of the weird edge cases. Other cases, like walking into an enemy or spikes from the side should do nothing special (no collision reaction), so the player continues walking through, and can even jump while "inside" the obstacle.