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.
golfed to 137: for(l=c.width+=i=0,h=400;++i<200;)for(j=a=(t+C(i))%2;j++<50;)x.fillRect(l*C(i*i)+~~a*(w=a*h-h)*C(j),(~~a?h:a*h)*(C(i)**2+2)+w*S(j)/4,3,3)
~ is a bitwise not. It flips all the bits in the number to the opposite. Flipping again (~~) puts the bits back to what they were. It works does something similar to floor because it truncates floats to 32-bit integers as part of the operation. (But unlike floor, ~~-2.1 is -2 instead of -3.)
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)