- shorten str8_lit macro to STR8
- use strlen() in STR8 and remove str8_from_cstring(). Usage with string literal seem to always be optimized by compile-time constant, so there's little need for a confusing macro that only works with literals and breaks with pointers.
- replaced str8_unbox() with str8_lp/str8_ip
- Reverted to using 4 bits of subpixel precision and computing cross products with 32 bits integers, for perf reasons
- Fixed some confusion in tile array size vs number of elements (could still clean-up naming a bit though)
- Fixed bug where triangles on the left or below canvas boundaries where bucketted to the first colum/row of tiles
- Fixed bug in mouse button message handling (was always sending press on left button)