Non-existant object detection!

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SuperSonic7(Posted 2009) [#1]
Bah. I bet something really simple is the answer.

I'm making a tower defense game. Turrets shoot enemies. The bullet's supposed to delete itself. I keep getting a "memory access violation". When I ran the game in debug, it said that "object does not exist" that is, "bullet.typBullet".



I think it's trying to do collision detection or move the bullet (bullet\x = bullet\x + 5) when there is no bullet, but i don't know how to fix this. any help is nice.


Floyd(Posted 2009) [#2]
In general you test for an object's existence by comparing with Null:
If MyObject <> Null Then DoSomething
However, in your case I think you could simply do the loops in the other order: first enemy then bullet.

Think about what happens after a bullet is deleted. The way the loops are now you move on to the next enemy, still trying to use the current bullet which was just deleted. Thus ImagesCollide fails.


SuperSonic7(Posted 2009) [#3]
Thanks, my problem is solved! If I ever get this thing done, you will be credited for your services.