| 1 | (function(){ |
| 2 | window.HPX = window.HPX || {}; |
| 3 | window.HPX['confetti-cannon'] = function(el){ |
| 4 | const U = window.HPX._u; |
| 5 | const k = U.canvas(el), ctx = k.ctx; |
| 6 | const pal = U.palette(el); |
| 7 | let parts = []; |
| 8 | const fire = () => { |
| 9 | for (let side=0; side<2; side++){ |
| 10 | const x0 = side===0 ? 20 : k.w-20; |
| 11 | const y0 = k.h - 20; |
| 12 | for (let i=0;i<40;i++){ |
| 13 | const a = side===0 ? U.rand(-Math.PI*0.7, -Math.PI*0.4) : U.rand(-Math.PI*0.6, -Math.PI*0.3) - Math.PI/2 - Math.PI/6; |
| 14 | const spd = U.rand(300, 520); |
| 15 | parts.push({ |
| 16 | x: x0, y: y0, |
| 17 | vx: Math.cos(a)*spd, vy: Math.sin(a)*spd, |
| 18 | w: U.rand(6,12), h: U.rand(3,7), |
| 19 | rot: Math.random()*Math.PI, vr: U.rand(-6,6), |
| 20 | c: pal[(Math.random()*pal.length)|0], |
| 21 | life: 1 |
| 22 | }); |
| 23 | } |
| 24 | } |
| 25 | }; |
| 26 | fire(); |
| 27 | let last = 0; |
| 28 | const stop = U.loop((t) => { |
| 29 | ctx.clearRect(0,0,k.w,k.h); |
| 30 | if (t - last > 3) { fire(); last = t; } |
| 31 | const dt = 1/60; |
| 32 | parts = parts.filter(p => p.life > 0 && p.y < k.h+40); |
| 33 | for (const p of parts){ |
| 34 | p.vy += 520*dt; |
| 35 | p.x += p.vx*dt; p.y += p.vy*dt; |
| 36 | p.rot += p.vr*dt; |
| 37 | p.life -= 0.006; |
| 38 | ctx.save(); |
| 39 | ctx.translate(p.x, p.y); ctx.rotate(p.rot); |
| 40 | ctx.globalAlpha = Math.max(0, p.life); |
| 41 | ctx.fillStyle = p.c; |
| 42 | ctx.fillRect(-p.w/2, -p.h/2, p.w, p.h); |
| 43 | ctx.restore(); |
| 44 | } |
| 45 | ctx.globalAlpha = 1; |
| 46 | }); |
| 47 | return { stop(){ stop(); k.destroy(); } }; |
| 48 | }; |
| 49 | })(); |
| 50 |