JavaScript Canvas 实现玫瑰绽放动画效果

核心代码实现

<html>
  <head>
  </head>
  <body>
    <canvas id="c"></canvas>
    <script>
 var b = document.body;
 var c = document.getElementsByTagName('canvas')[0];
 var a = c.getContext('2d');
 document.body.clientWidth;</script>
    <script>
with (m = Math)
  C = cos, S = sin, P = pow, R = random;
c.width = c.height = f = 500;
h = -250;
function p(a, b, c) {
  if (c > 60)
    return [ S(a * 7) * (13 + 5 / (.2 + P(b * 4, 4))) - S(b) * 50,
        b * f + 50,
        625 + C(a * 7) * (13 + 5 / (.2 + P(b * 4, 4))) + b * 400,
        a * 1 - b / 2, a ];
  A = a * 2 - 1;
  B = b * 2 - 1;
if(A*A+B*B<1){if(c>37){n=(j=c&1)?6:4;o=.5/(a+.01)+C(b*125)*3-a*300;w=b*h;return[o*C(n)+w*S(n)+j*610-390,o*S(n)-w*C(n)+550-j*350,1180+C(B+A)*99-j*300,.4-a*.1+P(1-B*B,-h*6)*.15-a*b*.4+C(a+b)/5+P(C((o*(a+1)+(B>0?w:-w))/25),30)*.1*(1-B*B),o/1e3+.7-o*w*3e-6]}if(c>32){c=c*1.16-.15;o=a*45-20;w=b*b*h;z=o*S(c)+w*C(c)+620;return[o*C(c)-w*S(c),28+C(B*.5)*99-b*b*b*60-z/2-h,z,(b*b*.3+P((1-(A*A)),7)*.15+.3)*b,b*.7]}o=A*(2-b)*(80-c*2);w=99-C(A)*120-C(b)*(-h-c*4.9)+C(P(1-b,7))*50+c*2;z=o*S(c)+w*C(c)+700;return[o*C(c)-w*S(c),B*99-C(P(b, 7))*50-c/3-z/1.35+450,z,(1-b/1.2)*.9+a*.1, P((1-b),20)/4+.05]}}setInterval('for(i=0;i<1e4;i++)if(s=p(R(),R(),i%46/.74)){z=s[2];x=~~(s[0]*f/z-h);y=~~(s[1]*f/z-h);if(!m[q=y*f+x]|m[q]>z)m[q]=z,a.fillStyle="rgb("+~(s[3]*h)+","+~(s[4]*h)+","+~(s[3]*s[3]*-80)+")",a.fillRect(x,y,1,1)}',0)</script>
  </body>
</html>