It was intended to make the API easier to use, but various automatic garbage collection all had flaws, and making the application periodically clean up temporary memory added cognitive load to using the API, and in many cases was it was difficult to restructure threaded code to handle this.
So, we're largely going back to the original system, where the API returns allocated results and you free them.
In addition, to solve the problems we originally wanted temporary memory for:
* Short strings with a finite count, like device names, get stored in a per-thread string pool.
* Events continue to use temporary memory internally, which is cleaned up on the next event processing cycle.
Move the Wayland pointer warp emulation code up to the SDL mouse layer, and activate it when a client attempts to warp a hidden mouse cursor when the hint is set.
testrelative adds the ability to test the warp emulation activation/deactivation with the --warp parameter and 'c' key for toggling cursor visibility.
This was just causing confusion and anxiety. SDL temporary memory will be automatically freed on the main thread when processing events and on other threads when it ages out after a second. The application can free it directly by calling SDL_ClaimTemporaryMemory() to get ownership of the pointer, if necessary.
We're limiting the functions to rects with positions and sizes < 1 billion for speed, which is totally fine for most SDL use cases. If you need rectangles larger than that, you can roll your own functions that use 64-bit intermediate values and do proper overflow handling of output values.
Fixes https://github.com/libsdl-org/SDL/issues/8879
* A floating point rectangle contains all points >= x and <= x + w
* A floating point rectangle is only empty if it has negative width. The zero rectangle contains the zero point.
* Adjacent floating point rectangles intersect along their shared side
Fixes https://github.com/libsdl-org/SDL/issues/6791
This allows threads to free memory from their local pool without affecting events that are queued, and to transfer memory ownership cleanly between threads that are queuing and dequeuing events.
Applying these changes to external code doesn't actually improve anything, and within the context of the other Get* functions for renderers and surfaces, these stand out as outliers, so I'm going to back this change out.
