Touch != Collision

I have a problem in my game with collisions, I need a very small collision polygon but at the same time I need for the whole object to be touched.

What I mean is that touch must be triggered upon touching any part of the sprite (the whole thing) while if I'm testing for collision with another sprite I need to check only a very small area.

How can I do this?

The usual trick is to use invisible sprites positioned over the object as a separate collision mask.

Ashley Thanks, I though about that, but what is the impact on performance (I'm on mobile so it's important)?

It's a puzzle game so there is an important amount of sprites on screen (around 40 which having their own sprite on top would mean 40visible + 40 invisible).

0plus1

Here's what I made. Would this be something you need?

http://dl.dropbox.com/u/53898431/Junk/Touch_collision_example.capx

I doubt there would be any more loss of performance than if you had multiple collision masks. They are essentially doing the same thing, at the end of the day.

That being said, multiple collision masks on single objects are on Ashley's to-do list, albeit quite far back (as more important stuff is needed beforehand, and that this has a workaround).

Use the 'pin' behavior so that you don't have to worry about it.

0plus1 - since performance is 90% rendering, if the sprite is invisible, there will not be any significant performance impact.