Mouse spiral paint #uncompressed as wis… by rodrigo.siqueira

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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rodrigo.siqueira

remix of d/34470 by u/ximavus

function u(t) {

t?onmousemove=e=>T=e:x.translate(960,w=i=540)
for(i=w;i--;x.rotate(1))x.fillStyle=R(z=i*i%255,z,z),x.fillRect(T.x*3.4-960,T.y*3.4-w,20,20)

Nov 2 2025 3:45 PM UTC

}// 138/140

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Mouse spiral paint #uncompressed as wished by u/ximavus

u/rodrigo.siqueira

My favorite trick here is onmousemove=e=>T=e:x , so you can get coords from T.x and T.y later. And the letter T prevents the "ReferenceError: X is not defined" initialization bug, since T is a previously defined variable.
u/rodrigo.siqueira

You can compress even more by changing the random component from i*i%255 to i*i%w but the image will be a little bit lighter.
u/rodrigo.siqueira

My second favorite trick here is the ternary operator: t?(...when t=0...):(...when t>0...)


      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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