htmlewislulu-html-ppt-skill/assets/animations/fx/_util.js

64 lines
1.9 KiB
JavaScript

/* html-ppt fx :: shared helpers */
(function(){
window.HPX = window.HPX || {};
const U = window.HPX._u = {};
U.css = (el, name, fb) => {
const v = getComputedStyle(el).getPropertyValue(name).trim();
return v || fb;
};
U.accent = (el, fb) => U.css(el, '--accent', fb || '#7c5cff');
U.accent2 = (el, fb) => U.css(el, '--accent-2', fb || '#22d3ee');
U.text = (el, fb) => U.css(el, '--text-1', fb || '#eaeaf2');
U.palette = (el) => [
U.accent(el, '#7c5cff'),
U.accent2(el, '#22d3ee'),
U.css(el, '--ok', '#22c55e'),
U.css(el, '--warn', '#f59e0b'),
U.css(el, '--danger', '#ef4444'),
];
U.canvas = (el) => {
if (getComputedStyle(el).position === 'static') el.style.position = 'relative';
const c = document.createElement('canvas');
c.style.cssText = 'position:absolute;inset:0;width:100%;height:100%;pointer-events:none;display:block;';
el.appendChild(c);
const ctx = c.getContext('2d');
let w = 0, h = 0, dpr = Math.max(1, Math.min(2, window.devicePixelRatio||1));
const fit = () => {
const r = el.getBoundingClientRect();
w = Math.max(1, r.width|0);
h = Math.max(1, r.height|0);
c.width = (w*dpr)|0;
c.height = (h*dpr)|0;
ctx.setTransform(dpr,0,0,dpr,0,0);
};
fit();
const ro = new ResizeObserver(fit);
ro.observe(el);
return {
c, ctx,
get w(){return w;}, get h(){return h;}, get dpr(){return dpr;},
destroy(){
try{ro.disconnect();}catch(e){}
if (c.parentNode) c.parentNode.removeChild(c);
}
};
};
U.loop = (fn) => {
let raf = 0, stopped = false, t0 = performance.now();
const tick = (t) => {
if (stopped) return;
fn((t - t0)/1000);
raf = requestAnimationFrame(tick);
};
raf = requestAnimationFrame(tick);
return () => { stopped = true; cancelAnimationFrame(raf); };
};
U.rand = (a,b) => a + Math.random()*(b-a);
})();