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gradient-blob.js
根目录 / assets / animations / fx / gradient-blob.js
1 (function(){
2 window.HPX = window.HPX || {};
3 window.HPX['gradient-blob'] = function(el){
4 const U = window.HPX._u;
5 const k = U.canvas(el), ctx = k.ctx;
6 const pal = U.palette(el);
7 const blobs = Array.from({length:4}, (_,i) => ({
8 x: U.rand(0,1), y: U.rand(0,1),
9 vx: U.rand(-0.08,0.08), vy: U.rand(-0.08,0.08),
10 r: U.rand(180,320),
11 c: pal[i%pal.length]
12 }));
13 const hex2rgb = (h) => {
14 const m = h.replace('#','').match(/.{2}/g);
15 if (!m) return [124,92,255];
16 return m.map(x=>parseInt(x,16));
17 };
18 const stop = U.loop((t) => {
19 ctx.fillStyle = 'rgba(10,12,22,0.2)';
20 ctx.fillRect(0,0,k.w,k.h);
21 ctx.globalCompositeOperation = 'lighter';
22 for (const b of blobs){
23 b.x += b.vx*0.01; b.y += b.vy*0.01;
24 if (b.x<0||b.x>1) b.vx*=-1;
25 if (b.y<0||b.y>1) b.vy*=-1;
26 const px = b.x*k.w, py = b.y*k.h;
27 const r = b.r + Math.sin(t*0.8 + b.x*6)*30;
28 const [R,G,B] = hex2rgb(b.c);
29 const grad = ctx.createRadialGradient(px,py,0,px,py,r);
30 grad.addColorStop(0, `rgba(${R},${G},${B},0.55)`);
31 grad.addColorStop(1, `rgba(${R},${G},${B},0)`);
32 ctx.fillStyle = grad;
33 ctx.beginPath(); ctx.arc(px,py,r,0,Math.PI*2); ctx.fill();
34 }
35 ctx.globalCompositeOperation = 'source-over';
36 });
37 return { stop(){ stop(); k.destroy(); } };
38 };
39 })();
40
40 lines JAVASCRIPT