SLE with a better RNG by Tesseract

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

Please log in (or register) to post a dweet (copy-paste the code somewhere safe to save it meanwhile)


    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.

show FPS hide FPS share fullscreen

Tesseract

remix of d/20438 by u/Odog8

function u(t) {

n=c.width=133
z=t?z+C(n*z):25
d=(b,a)=>[b-b/(k=(o=a-z)*o+b*b),a+o/k]
for(l=1e4;l--;)x.fillRect(...p=[l%n,l/n],1,(C[l]=t?d(...C[l]):p)[0]/4)

Oct 30 2020 6:18 PM UTC

}// 139/140

Please log in (or register) to post as a new dweet (copy-paste code somewhere safe to save it meanwhile).

SLE with a better RNG

Show more comments…
u/Odog8

What are these even used for?
u/Tesseract

It's very interesting mathematically - it corresponds to certain kinds of random walk that are hard to analyse otherwise. Some physicists also care about it.
u/Odog8

huh.
u/joeytwiddle

https://en.wikipedia.org/wiki/Schramm%E2%80%…
u/Odog8

Hey, could you explain how you made this further? The wikipedia doesnt do as good of a job as i would have liked :(
u/Tesseract

I can't explain conformal mappings in a comment, but the central part is the function d, which sends z=a+bi to z+delta*dg_t(z)/dt (dg/dt is defined on Wikipedia). For brevity, I've set delta=1/2, so it's approximating d(g_t(z))=g_{t+1/2}(z). The complex number division is golfed. Brightness corresponds to the imaginary part of g_t(z). The javascript variable z is not a+bi, but is brownian motion - zeta(t) according to Wikipedia.
u/Tesseract

I made a non-golfed version in Python a while ago which might be easier to read: https://github.com/penteract/sle/blob/master…


      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)

dwitter.net