SDL3 support

[trexxet]

Shouldn't be hard, just a few patches to nuklear_sdl_gl3.h

Here's my working solution using CMake:

file(READ ${NUKLEAR_PREFIX_INCLUDE}/nuklear_sdl_gl3.h SDL_FILE_CONTENTS)
string(REPLACE "SDL2" "SDL3" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_GetTicks64" "SDL_GetTicks" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_GL_GetDrawableSize" "SDL_GetWindowSizeInPixels" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_TRUE" "true" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_FALSE" "false" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_KEYUP" "SDL_EVENT_KEY_UP" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_KEYDOWN" "SDL_EVENT_KEY_DOWN" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_MOUSEBUTTONUP" "SDL_EVENT_MOUSE_BUTTON_UP" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_MOUSEBUTTONDOWN" "SDL_EVENT_MOUSE_BUTTON_DOWN" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_MOUSEMOTION" "SDL_EVENT_MOUSE_MOTION" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_MOUSEWHEEL" "SDL_EVENT_MOUSE_WHEEL" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_TEXTINPUT" "SDL_EVENT_TEXT_INPUT" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDLK_b" "SDLK_B" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDLK_c" "SDLK_C" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDLK_e" "SDLK_E" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDLK_r" "SDLK_R" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDLK_v" "SDLK_V" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDLK_x" "SDLK_X" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDLK_z" "SDLK_Z" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "const Uint8* state = SDL_GetKeyboardState(0);" "const _Bool* state = SDL_GetKeyboardState(0);" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "SDL_SetRelativeMouseMode(" "SDL_SetWindowRelativeMouseMode(sdl.win, " SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
string(REPLACE "switch(evt->key.keysym.sym)" "switch(evt->key.key)" SDL_FILE_CONTENTS "${SDL_FILE_CONTENTS}")
file(WRITE ${NUKLEAR_PREFIX_INCLUDE}/nuklear_sdl_gl3.h "${SDL_FILE_CONTENTS}")

Also, please, add the extern "C" wrap to nuklear_sdl_gl3.h

[RobLoach]

Would love for either SDL_GPU or SDL_renderer implementation so it would work across different graphics platforms.

Two attempts that I know of...

1. lessthan3 started up a port of the sdl3_gl2 demos: Added demo updated for SDL3 #719
2. I've opened up a sdl3 branch with some initial attempts too

[trexxet]

Oh, should have searched for PRs - I have checked issues only.
Anyway, this patch may be useful for anyone trying to use SDL3 before official support.

[RobLoach]

Still worth to keep the issue open. Good to have a tracking thread, thanks 👍