[Feature Request] A new forced mapping type of a stick (left or right) to a touchpad or mouse can be valuable for controlling fps games with stick controls

Like the current dpad to stick only instead it is stick to (mouse or touchpad/overlay).

This would conflict a bit with some cores that already use the overlay for cursor pointing ofc, like dolphin, scummvm, dosbox (and I suppose cores with controllers like the wiiu, with touchpads themselves).

However it should still be possible to force these settings even in those cores. The point of this idea is to make games that dont support a "mouse like" controller mode and opt to use sticks to orient the camera to use a more precise and controllable user interface device, so that more precise device has to control the stick.

Indeed I thought of this while testing Deus Ex Human Revolution on the wiiu cemu core, and that console has a touch sensitive screen on the controller. However, its not used in this game for camera orientation (or anything but minigames which dont use the touchpad afaik).

Mouse was mentioned as also a useful possibility by ML on discord.

Start by tracing RetroArch's existing dpad-to-stick mapping and the input paths used for mouse, touchpad, and overlay controls. Compare behavior with cores such as dolphin, scummvm, dosbox, and the wiiu/cemu core; done means a forced stick-to-mouse or touchpad mapping works without unexpectedly breaking those core-specific controls.