- SDL_RWops is now an opaque struct.
- SDL_AllocRW is gone. If an app is creating a custom RWops, they pass the
function pointers to SDL_CreateRW(), which are stored internally.
- SDL_RWclose is gone, there is only SDL_DestroyRW(), which calls the
implementation's `->close` method before freeing other things.
- There is only one path to create and use RWops now, so we don't have to
worry about whether `->close` will call SDL_DestroyRW, or if this will
risk any Properties not being released, etc.
- SDL_RWFrom* still works as expected, for getting a RWops without having
to supply your own implementation. Objects from these functions are also
destroyed with SDL_DestroyRW.
- Lots of other cleanup and SDL3ization of the library code.
This reverts commit b9ab326982.
@rainerdeyke pointed out:
"This commit is incorrect. Flipping both horizontally and vertically is not equivalent to flipping diagonally."
Since SDL_RenderFlip is an enum, SDL_FLIP_HORIZONTAL and SDL_FLIP_VERTICAL can not be OR'ed to get the "SDL_FLIP_DIAGONAL".
Render code is actually able to perform these 3 kind of "flipping" so I just added a new enum called SDL_FLIP_DIAGONAL with the OR'ed value (3) so it can be used.
This better reflects how HDR content is actually used, e.g. most content is in the SDR range, with specular highlights and bright details beyond the SDR range, in the HDR headroom.
This more closely matches how HDR is handled on Apple platforms, as EDR.
This also greatly simplifies application code which no longer has to think about color scaling. SDR content is rendered at the appropriate brightness automatically, and HDR content is scaled to the correct range for the display HDR headroom.
We'll use properties for new data associated with a surface, which lets us preserve ABI compatibility with SDL2 and any surfaces created by applications and passed in to SDL functions.
The following objects now have properties that can be user modified:
* SDL_AudioStream
* SDL_Gamepad
* SDL_Joystick
* SDL_RWops
* SDL_Renderer
* SDL_Sensor
* SDL_Surface
* SDL_Texture
* SDL_Window
The current status is stored in the SDL_rwops 'status' field to be able to determine whether a 0 return value is caused by end of file, an error, or a non-blocking source not being ready.
The functions to read sized datatypes now return SDL_bool so you can detect read errors.
Fixes https://github.com/libsdl-org/SDL/issues/6729
