Slow down clock time / bullet time

Questions
, ,
1

I’m trying to slow down the scene globally - animations/physics/transformations, etc. As it is done in F.E.A.R., max payne or nfs, for example, with a smooth transition from/to slowdown when you press the button. But so far I don’t see any way to implement this through threejs api. What can be done in this situation? What threejs or webgl api’s should be used? Maybe there’s some hidden global multiplier?

2

Hello! Three.js use delta time for animations. For 60 fps delta time is 0.016 second or 16 miliseconds.

var slow_down=0;
var slow_up=0;
var slow_v=0.016;


function loop(){

requestAnimationFrame(loop);
delta=clock.getDelta(); // 0.016ms

if(slow_down==1){
if(slow_v>0.002){ slow_v-=0.0001; }
delta=slow_v;
}

if(slow_up==1){
slow_down=0; // set it in function of keypress
if(slow_v<0.016){ slow_v+=0.0001; }
if(slow_v>0.015){ slow_v=0.016; slow_up=0; }
delta=slow_v;
}

controls.update(delta);

var max=mixers.length;
for(var n=0;n<max;n++){
mixers[n].update(delta);
}

}
3

Good test into “Silent Hill”.

4

Hi there!
Thank you so much for reply.
But i do scenes in react three fiber and i have custom fps controls, and no access to ‘controls’ in frame loop. And player camera is physics based (cannonjs via use-cannon)

Could you please look into my sandbox?

?

5

I dont know react three fiber . In example found only this:
clock.getElapsedTime()
but for slowdown need calculate like this also:
delta=clock.getDelta();

6

i can alter delta but this results in choppy motion (like 10 fps)
how can i lerp it right in 60 fps?

7

Only who know what is “react three fiber” can help.

8

Maybe by adjusting some time delta multiplicators and multiplying them with current delta

export function Updater() {
  const timeDeltaModificator: number = useSelector(selectTimeDeltaModificator);

  useFrame((state: RootState, delta: number) => {
    yourUpdateFunction({ delta: delta * timeDeltaModificator });
  });

  return ( <mesh /> );
}

This way you will still have your N (60?) fps, but with slowed-down physics, animations, etc.