Initial Collision Detection in Pygame

Question

I recently have run into a problem with a simple collision detection test in my Pygame project. I am purposely not using the Sprite class and some of the built in collision functions provided by Pygame for learning purposes. The problem I am having is not that the collisions aren't detected. The problem is that the collisions are lasting longer than they should be.

If you run my code, you will see that the Obstacle objects randomly falling down the screen pass through the Player object for some time, even after they have disappeared. collisions counts the number of coordinates that the Obstacle passes through Player , which seems to typically be in-between -17 to -21. Why is this happening? Since the boolean obstacle.exists = False is stated, shouldn't the Obstacle object be instantly destroyed before it has time to pass through Player -17 to -21 intersecting coordinates? Could this possibly be caused by an fps issue?? Basically, what I am trying to figure out is how to get Obstacle to be destroyed instantly upon collision, so that collisions only subtracts once.

Answer 1

Your collision detection is made regardless of the existence of an obstacle. You should add obstacles.exists as first test on your collision détection:

if (obstacles.exists and 
        obstacles.x < player.x + player.w and
        obstacles.x + obstacles.w > player.x and
        obstacles.y < player.y + player.h and
        obstacles.h + obstacles.y > player.y):
    #do stuff