Force backslashes to slashes for embedded paths

[skeeto]

On Windows the paths are joined using backslashes, but these backslashes are not properly escaped for a C string when printed, resulting in the wrong string in the include. I ran into this when building csprite natively on Windows using Mingw-w64 (via).

More generally, to successfully build and run (in place) on Windows — which I was happy to see working! — I also had to:

1. Adjust subprocess.run(['clang++', ...] to 'g++'
2. Add SDL2 -I/-L paths to CCFLAGS/LFLAGS (alternative: install SDL2 in the GCC sysroot like on other platforms)
3. Adjust python3 to python since that's what it's named on Windows

For (1), this could be 'c++' to invoke the system's primary C++ compiler, whether that's clang++ or g++, just like cc for the C compiler. (Note: You can do the same with CXX in the Makefile.)

For (2) the Makefile could use sdl2-config, which is part of SDL2 and exists specifically to solve this problem. (Note the double $$.)

CCFLAGS:=... $$(sdl2-config --cflags)
LFLAGS+=... $$(sdl2-config --static-libs) ...   # static link
LFLAGS+=... $$(sdl2-config --libs) ...          # dynamic link

The sources also need to be updated to include SDL.h rather than SDL2/SDL.h which is the incorrect include anyway. (Maybe also get rid of -DSDL_MAIN_HANDLED=1 since it doesn't seem to serve a purpose in this case? I suspect it's only there to simplify linking.)

For (3) add a PYTHON variable a la CXX. This would also work better in virtual environments, e.g. make PYTHON=venv/bin/python.

[pegvin]

Hey, thanks for the PR! i didn't really thought of this as my whole workflow is generally on linux.

sorry for the inconvenience with the build system, i will address all those issues by raising a new issue.

Happy New Year!

[pegvin]

also the makefile was designed according to msys2 environment on windows so it might or might not fail when building on any other environment, i will be adding msvc support & mingw soon.