#default on a sphere by pavel

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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pavel

function u(t) {

for(c.width=i=1944,w=960;i--;x.fillRect(w+w*S(a)*S(b)/z,540+w*C(b)/z,s=13/z/z,s))j=i%72,z=2+C(a=2.7+S(t)+(j&4?0:j)/72)*S(b=1.5+(i/72|0)/120)

Apr 11 2019 6:03 AM UTC

}// 140/140

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#default on a sphere

u/f8f82804

#d3 #sphere #perspective
u/katkip

how lol
u/pavel

I draw #default one pixel at a time and treat (x,y) of the pixels as angles (a,b) in spherical coordinates. Spherical to 3d cartesian is x=r*sin(a)*sin(b), y=r*cos(a)*sin(b), z=r*cos(b). Projecting 3d to 2d cartesian is x'=x/(2+y/r), y'=z/(2+y/r), and scaling pixel size by 1/(2+y/r)**2 so stuff in the back is smaller.


      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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