43 lines
1.2 KiB
JavaScript
43 lines
1.2 KiB
JavaScript
(function(){
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window.HPX = window.HPX || {};
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window.HPX['particle-burst'] = function(el){
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const U = window.HPX._u;
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const k = U.canvas(el), ctx = k.ctx;
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const pal = U.palette(el);
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let parts = [];
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const spawn = () => {
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const cx = k.w/2, cy = k.h/2;
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const n = 90;
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for (let i=0;i<n;i++){
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const a = Math.random()*Math.PI*2;
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const s = U.rand(80, 260);
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parts.push({
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x: cx, y: cy,
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vx: Math.cos(a)*s, vy: Math.sin(a)*s,
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life: 1, r: U.rand(2,5),
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c: pal[(Math.random()*pal.length)|0]
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});
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}
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};
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spawn();
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let lastSpawn = 0;
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const stop = U.loop((t) => {
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ctx.clearRect(0,0,k.w,k.h);
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if (t - lastSpawn > 2.5) { spawn(); lastSpawn = t; }
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const dt = 1/60;
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parts = parts.filter(p => p.life > 0);
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for (const p of parts){
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p.vy += 220*dt;
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p.vx *= 0.985; p.vy *= 0.985;
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p.x += p.vx*dt; p.y += p.vy*dt;
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p.life -= 0.012;
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ctx.globalAlpha = Math.max(0, p.life);
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ctx.fillStyle = p.c;
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ctx.beginPath(); ctx.arc(p.x, p.y, p.r, 0, Math.PI*2); ctx.fill();
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}
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ctx.globalAlpha = 1;
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});
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return { stop(){ stop(); k.destroy(); } };
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};
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})();
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