This is the way I like it:
- Only call fpc on hwengine.pas, let compiler rule the dependencies
- Make hwengine.pas depend on all other source files, so 'make' always calls fpc
allow SDL 1.2 to at least do a 32767 map. We probably should add a TryDo somewhere to assert that limit on SDL 1.2 to avoid overflows. Ditto int version for SDL 2