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constellation.js
根目录 / assets / animations / fx / constellation.js
1 (function(){
2 window.HPX = window.HPX || {};
3 window.HPX['constellation'] = function(el){
4 const U = window.HPX._u;
5 const k = U.canvas(el), ctx = k.ctx;
6 const ac = U.accent(el,'#9fb4ff');
7 const N = 70;
8 let pts = [];
9 const seed = () => {
10 pts = Array.from({length:N}, () => ({
11 x: Math.random()*k.w, y: Math.random()*k.h,
12 vx: U.rand(-0.3,0.3), vy: U.rand(-0.3,0.3)
13 }));
14 };
15 seed();
16 let lw=k.w, lh=k.h;
17 const stop = U.loop(() => {
18 if (k.w!==lw||k.h!==lh){ seed(); lw=k.w; lh=k.h; }
19 ctx.clearRect(0,0,k.w,k.h);
20 for (const p of pts){
21 p.x += p.vx; p.y += p.vy;
22 if (p.x<0||p.x>k.w) p.vx*=-1;
23 if (p.y<0||p.y>k.h) p.vy*=-1;
24 }
25 for (let i=0;i<N;i++){
26 for (let j=i+1;j<N;j++){
27 const a=pts[i], b=pts[j];
28 const d = Math.hypot(a.x-b.x, a.y-b.y);
29 if (d < 150){
30 ctx.globalAlpha = 1 - d/150;
31 ctx.strokeStyle = ac; ctx.lineWidth=1;
32 ctx.beginPath(); ctx.moveTo(a.x,a.y); ctx.lineTo(b.x,b.y); ctx.stroke();
33 }
34 }
35 }
36 ctx.globalAlpha = 1;
37 ctx.fillStyle = ac;
38 for (const p of pts){
39 ctx.beginPath(); ctx.arc(p.x,p.y,1.8,0,Math.PI*2); ctx.fill();
40 }
41 });
42 return { stop(){ stop(); k.destroy(); } };
43 };
44 })();
45
45 lines JAVASCRIPT