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iOS Build a Game with Sprite Kit Physics and Collision Collision Masks and Movement

Natalie Carlson
Natalie Carlson
3,727 Points

In the bit mask, the comment section says the the THCollisionCategoryEnemy is 0000. Why wouldn't it be 0001 instead?

If 1<< 0 means move 1 left zero times, wouldn't the THCollisionCategoryEnemy be 0001 instead of 0000?

Eric Hodgins
Eric Hodgins
29,207 Points

You probably figured this out already. But I think you're right. It should be 0001 (well 31 0's in front of the 1). If you:

NSLog("%d", THCollisionCategoryEnemy);

The value is 1 or 0001.