Added Fixed Physics Steps feature and Renamed the 'Use Frame Rate' to…

[vuaieo]

… 'FPS Limit' because its the most common describtions in any game engine to understand what it do... and moved it to the Game Physics panel in Scene properties editor becuase it affects the physics fundamentaly when using Variable mode

[youle31]

Hello, I quickly tested, it sounds ~ok overhaul but there are several things to fix.

In my human vocabulary:

• python API is missing for the new functions in bge.logic.rst
• when we set physics steps to 30 instead of 60 in fixed mode, the displayed framerate by the bge profiler sounds messed -> display values like 500000 fps.
• std::sleep_for can cause stutters dépending on platforms, it's why I commented it. You can use it if you want but use it with "busy wait" -> ask gpt or the AI you use about that. I think it is the reason why when I enable fixed mode with use_fixed_fps_cap set to 60, the displayed FPS on my computer is 57/58.
• Please enable use_fixed_fps_cap by default (both for consistency with variable mode and energy savings)
• UI is a bit confusing about Physics steps (Physics steps per second). Same name for max physics steps and physics steps per second.

EDIT: I edited my review because timescale and external clock time were taken into account

On my side, I will change UpdateSoftBody function name to UpdateSoftBodyRenderedShape