JS1k: The JavaScript code golfing competition

eval('c.style.cursor="pointer";b.style.textAlign="center";var g=c.style;g.border="solid 5px #000";g.boxShadow="6px 6px 10px #666";~ S(e,h,f){e=e+h*w<<2;dd[e]=f.r;dd[++e]=f.g;dd[++e]=f.b;dd[++e]=f.a}~ G(e,h){var f=e+h*w<<2;@{r:dd[f],g:dd[++f],b:dd[++f],a:dd[++f]}}~ D(e){@{r:e.r+MF(20*MR()+0.75)-10,g:e.g+MF(20*MR()+0.75)-10,b:e.b+MF(20*MR()+0.75)-10,a:255}}~ A(e,h){@{r:e.r+h.r>>1<<0,g:e.g+h.g>>1<<0,b:e.b+h.b>>1<<0,a:255}}~ V(){@ MF(256*MR())}~ R(){@{r:V(),g:V(),b:V(),a:255}}~ M(){for(var e=0;e<dd.length-4*w;e++)dd[e]=dd[e+4*w];var e=w-1,h=D(G(0,e-1));S(0,e,h);for(var f=1;f<w;f++)h=D(A(G(f,e-1),G(f-1,e))),S(f,e,h);a.putImageData(d,0,0);setTimeout("M()",10)}~ H(){d=a.createImageData(w,w);dd=d.data;var e=R();S(0,0,e);for(var h=1;h<w;h++)S(h,0,e=D(e));for(var e=G(0,0),f=1;f<w;f++)S(0,f,e=D(e));for(f=1;f<w;f++)for(h=1;h<w;h++)S(h,f,D(A(G(h,f-1),G(h-1,f))));a.putImageData(d,0,0)}var d,dd,MF=Math.floor,MR=Math.random,w=c.width=c.height=400;H();c.onclick=~(){H()};M()'.replace(/~/g, 'function').replace(/@/g, 'return'))

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

Original source not submitted