Infinite hopscotch by Joachim

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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Joachim

function u(t) {

for(i=z=c.width=300;i--;x.fillRect(140+a*i+C(t*9)*30,90+i*(S(t*9%3.1)/9+.3),i,i/z))a=T(z^z/i+t*4),x.fillStyle=R(b=a*z,S(b)*z,T(b)*z)

Apr 13 2022 9:23 AM UTC

}// 132/140

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Infinite hopscotch

u/Odog8

Thats nuts
u/Joachim

This 3D-like technique is useful for making single-direction ground textures. This is roughly how it works: A rectangle with a height of ~1px is drawn for every row of pixels on the screen. The width of every rectangle depends on how far down it is (their index). The x position of every rectangle is defined by this bit of code: T(z^z/i+t*9). This is then multiplied by their index to achieve a 3D look, as everything gets bigger & faster near the bottom of the screen. Without the animation or colours, the entire thing can get as small as 64 char: for(i=z=c.width=300;i--;)x.fillRect(140+T(z^z/i+t*9)*i,90+i,i,1). Feel free to get it even smaller!
u/vain

@u/Joachim: Thanks a lot for the litte explanation and example. =)
u/Joachim

#d3 #perspective #mist #colors
u/lineburgb

for(i=z=c.width=300;i--;)x.fillRect(140+T(z^z/i+t*9)*i,90+i,i,1)


      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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