Read/write memory on tick command

[Skarsnik]

We could have write and read command that ensure that they are run on the emulator tick and when the emulation is "paused".

I call that tick since I am not sure how the term frame applies for emulators that run at more than the original fps of the console, like some 3d emu that runs at 60 fps instead of the original 20-30 fps.

CORE_WRITE_ON_TICK CORE_READ_ON_TICK

[black-sliver]

from an emulation perspective, it would still be frame. just that the display fps is different than the emulation fps. i'm not sure to what extend we should provide both since other protocols do not support both. i would rather add a hint "prefer write on vblank" or similar

[Skarsnik]

It's probably easier to write on like the gui/display tick than the underlying emulation 'frame' for most emulators, especially something like RetroArch that support multiple cores. The difference for me with the other write/read is having something that ensure that the client gets/write its data in 'safe' way.
This also marks the fact that these commands could slow down the emulation process if you need to pause the emulation or add something to lock the memory accessed

[black-sliver]

That's why i would do it through a hint ("application needs safe writes"). Either your application needs it to be "safe", or it does not. Doing a "safe" followed by an "unsafe" write would have the "unsafe" wait for the "safe" to be finished, so supporting both does not help in performance.