31 lines
990 B
JavaScript
31 lines
990 B
JavaScript
(function(){
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window.HPX = window.HPX || {};
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window.HPX['starfield'] = 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 tx = U.text(el, '#ffffff');
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const N = 260;
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const stars = Array.from({length:N}, () => ({
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x: U.rand(-1,1), y: U.rand(-1,1), z: Math.random()
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}));
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const stop = U.loop(() => {
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ctx.fillStyle = 'rgba(0,0,0,0.25)';
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ctx.fillRect(0,0,k.w,k.h);
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const cx = k.w/2, cy = k.h/2;
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for (const s of stars){
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s.z -= 0.006;
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if (s.z <= 0.02) { s.x = U.rand(-1,1); s.y = U.rand(-1,1); s.z = 1; }
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const px = cx + (s.x/s.z)*cx;
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const py = cy + (s.y/s.z)*cy;
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if (px<0||py<0||px>k.w||py>k.h) continue;
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const r = (1-s.z)*2.4;
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ctx.globalAlpha = 1-s.z;
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ctx.fillStyle = tx;
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ctx.beginPath(); ctx.arc(px,py,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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