obsidian-visualiser/composables/useTween.ts

54 lines
1.5 KiB
TypeScript

import { clamp, lerp } from "~/shared/general.utils";
export const linear = (progress: number): number => progress;
export const ease = (progress: number): number => -(Math.cos(Math.PI * progress) - 1) / 2;
export function useTween(ref: Ref<number>, animation: (progress: number) => number, then: () => void)
{
let initial = ref.value, current = ref.value, end = ref.value, progress = 0, time = 0, animationFrame: number, stop = true, last = 0;
function loop(t: DOMHighResTimeStamp)
{
const elapsed = t - last;
progress = clamp(progress + elapsed, 0, time);
last = t;
const step = animation(clamp(progress / time, 0, 1));
current = lerp(initial, end, step);
then();
if(progress < time && !stop)
{
animationFrame = requestAnimationFrame(loop);
}
else
{
progress = 0;
stop = true;
}
}
return {
stop: () => {
cancelAnimationFrame(animationFrame);
stop = true;
},
update: (target: number, duration: number) => {
initial = current;
time = duration + progress;
end = target;
ref.value = target;
if(stop)
{
stop = false;
last = performance.now();
loop(performance.now());
}
},
refresh: () => { current = ref.value; },
current: () => { return current; },
};
}