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.
Deleted my previous attempt and replaced it with this instead because I found an obvious savings that allowed me to improve rect size. If you can save 5 chars, you can replace s*S(t) with (s-28)*S(t) to center the rotation. Alternatively, if you can save one char, you can remove b, make the last two args of fillRect…,4*i/t,4), and use the previous centering method with a small concession to the rect shape.
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)