Broken parallax scrolling effect (only … by joeytwiddle

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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joeytwiddle

function u(t) {

t||(Y=0)
onmousemove=e=>{Y=e.pageY*.7}
c.width=568;for(y=320;y--;x.fillRect(0,y,568,1))x.fillStyle=`hsl(${30*((y-Y)/30|0)},99%,50%`

Jul 14 2019 5:01 AM UTC

}// 131/140

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Broken parallax scrolling effect (only works if you wiggle your mouse over the dweet while you scroll the page)

u/joeytwiddle

I tried various things but I couldn't find any way for the iframe to know when it has been scrolled. :-/
u/katkip

It impossible. Iframe's cursor doesn't update if mouse isn't moving inside iframe


      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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