u(t) is called 60 times per second.
t: Elapsed time in seconds.
S: Shorthand for Math.sin.
C: Shorthand for Math.cos.
T: Shorthand for Math.tan.
R: Function that generates rgba-strings, usage ex.: R(255, 255, 255, 0.5)
c: A 1920x1080 canvas.
x: A 2D context for that canvas.
I didn't catch the color change, it does complicated the code: 138 for(r=Math.random,w=i=2e3;i--;x.fillRect(S[i]+=4-8*r(),C[i]+=4-8*r(),2,2))c[t]=S[t]=w*r(),x[t]=C[t++]=w*r(),x.fillStyle=R(0,c[i]/8,x[i]/4)
u(t) is called 60 times per second.
t: elapsed time in seconds.
c: A 1920x1080 canvas.
x: A 2D context for that canvas.
S: Math.sin
C: Math.cos
T: Math.tan
R: Generates rgba-strings, ex.: R(255, 255, 255, 0.5)