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galaxy-swirl.js
根目录 / assets / animations / fx / galaxy-swirl.js
1 (function(){
2 window.HPX = window.HPX || {};
3 window.HPX['galaxy-swirl'] = 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 N = 800;
8 const parts = Array.from({length:N}, (_,i) => {
9 const arm = i%3;
10 const t = Math.random();
11 const r = t*180 + 8;
12 const base = (arm/3)*Math.PI*2;
13 return { r, a: base + Math.log(r+1)*1.6 + U.rand(-0.2,0.2),
14 c: pal[arm%pal.length],
15 s: U.rand(0.8, 2.2) };
16 });
17 const stop = U.loop((t) => {
18 ctx.fillStyle = 'rgba(0,0,0,0.15)';
19 ctx.fillRect(0,0,k.w,k.h);
20 const cx=k.w/2, cy=k.h/2;
21 for (const p of parts){
22 const a = p.a + t*0.15;
23 const x = cx + Math.cos(a)*p.r;
24 const y = cy + Math.sin(a)*p.r*0.7;
25 ctx.fillStyle = p.c;
26 ctx.globalAlpha = 0.7;
27 ctx.beginPath(); ctx.arc(x,y,p.s,0,Math.PI*2); ctx.fill();
28 }
29 ctx.globalAlpha = 1;
30 });
31 return { stop(){ stop(); k.destroy(); } };
32 };
33 })();
34
34 lines JAVASCRIPT