Enumeration MainLoopType

update() will be called every frame (like Render). However, if a frame takes longer than 60 FPS it'll be called with 1/60 elapsed.

This will cause update's elapse-value retains stable in situations of low FPS.

update() is called on a fixed fixed rate with a (mostly) fixed elapse-value.

set fixedMainloopFps to control this.

            A
         [----]
         F    F          F
         v    v          v
-----|------------------------------------|---------------> t
     1sec     ^                           2sec
              |
           render()

When render() is called the delta-time (A) is calculated.
Dependning on the fixedMainloopFps update() is called for all frames
that fit into (A).

For example if (A) is 0.3sec and fixedMainloopFps is 60 it would mean that
update is called 0.3*60 => 18 times before the rendering is called. That way
the update calls will always have the same elapsed value.

update() will be in full sync with the the fps of the game.