Jump-thru platform glitch?

I've been working on a basic example level for people to learn basic patrolling enemy behaviour with platform movement when I discovered an interesting glitch.

If you time the 'jump' event to go off when you're landing on a "jump-thru" object, you can fall through the surface.

http://www.johnnysix.net/games/PatrolExample/

CAPX

Is this a consequence of scaling - I was reading through old posts of similar issues and a guy was having issues with things going into the floor a pixel, or colliding a pixel away from a wall.

Link to capx returns a 404 error.

I know what the problem is - the collision changes.

Because the enemies ( and the player character ) animate a cycle of getting taller/shorter , it seems the collision hits aren't reliable.

I was thinking that with the origin being at the bottom of the sprite, the minor height changes wouldn't make a difference, but it seems they do.

Updated link :

http://www.johnnysix.net/games/PatrolExample/PatrolExample8.capx

# Extension was lowercase!

I can't see what the problem is in that .capx in r87. Am I missing something?

It is standard practice to use the Platform behavior on an invisible rectangular sprite with no animations. This avoids glitches caused by the object size/collision mask changing and you should always do it. Does that prevent the problem? If so, I would not consider this a bug.

Hi Ashley,

I do use the invisible sprite+animations in other projects, but I was thinking it only mattered in instances where the collision changed on the positive y-axis relative to the origin.

I'll do an updated demo without cropping the animation- I was trying to keep it simple for new users by not piling on too many things to learn at once, and left out the pinning/invisible sprite part.