Warn when SDL directory doesn't exist

[ghost]

This is the alternate "fix", still doesn't automatically include the SDL2 from system files, but avoids some confusion (that i had lul)

This is the code, i dont work on makefiles and it uses shell commands, there is a also one that doesnt but looks worse, i dont if this works on windows tho:

ifeq ($(PLATFORM),PLATFORM_DESKTOP_SDL)

NEW:

    if [ ! -d "$(SDL_INCLUDE_PATH)" ]; then \
        echo "SDL Include directory doesn't exist: $(SDL_INCLUDE_PATH)"; \
    fi

    INCLUDE_PATHS += -I$(SDL_INCLUDE_PATH)
endif

Here i made a discussion if you have any suggestions, tell me and we can turn this into a PR!

[raysan5]

@mr-sihc I think there is no need for that, if the SDL.h include is not found, it will complain that it's not found.

[ghost]

hmm, well was kinda confusing on why since everything else just used my system install and so when something didnt compile, i am like: "well somethings wrong with the program, everything else i ever compiled with SDL JUST worked!"

maybe someone (not me idk makefiles) can make it use the system dir

OR

we just have SDL as a subproject

or nothing :,(