Tilemap: Consider enabling spartial hash by default

[einarf]

I've seen a lot of of people not enabling spatial hashing in their tilemap layers. Possibly we should just do this by default because it's what most people need. Not enabling it have devastating consequences to performance.

[Cleptomania]

It's a tough question, I'm not really against it, if it seems to be the common case then I'm fine with it. I think most games are realistically going to have a mix of layers that they need it on for and off for, maybe we need to do a better job of communicating it in docs?

I suppose it's probably likely that enabling spatial hash on the layers which shouldn't have it, generally speaking, is probably less substantial of a problem than not enabling it on the layers that do need it.

[einarf]

Still a bit on the fence about this. We can let this brew a bit longer. It implies updating examples as well. For my personal use I'd prefer it explicit just like it is now. You might be right that it's a doc issue.