These SDL2_gfx examples were copied from SDL2 gfx tutorial. They have been very slightly altered to compile with Make under both MSYS2/MinGW and Linux.
Makefile: Builds examples with GNU Make for either Windows (MSYS2/MinGW) or Linux.
test.c: Test sdl_gfx that whether works or not
shapeguide.c: Guide to sdl_gfx functions
sin.c: Draw sine function with keyboard events
wave.c: Draw wave with keyboard events