d/23766 by taupelink

function u(t) {

c.width=1920 // clear the canvas
for(i=0;i<9;i++)
x.fillRect(400+i*100+S(t)*300,400,50,200) // draw 50x200 rects

} // 122/140

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    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.

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taupelink

remix of d/23760 by u/taupelink

function u(t) {

for(i=q=k=810;--i;x.fillRect(k*X,k-q*Y,-i/v,q*Y/v))f=i*t,X=f*f%5,Y=X*f%4-2,x.fillStyle=R(s=q+i*Y*.4,q^=-s,q^=255,(k+q)*(Y+3)**2/4e4),v=4**t

Sep 6 2021 6:21 AM UTC

}// 139/140

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d/23766

u/rep_movsd

You need to write a blog about this particular technique
u/taupelink

i'd like to, but it would take time (i'm a super slow writer) and it's honestly not a priority at the moment. I can at least say this: Part of how I get four vertical bands is having Y range from less than -1 to greater than 1 (in this case, -2 to 2). Multiplying or dividing by Y then has four effects: stretch or compress, do or do not reverse sign
u/rep_movsd

A one page breakdown would be nice, or perhaps I'll write one
u/taupelink

ah ok...like a line-by-line explanation? that's doable...i'll write something up next weekend!


      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)

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