Dweets awesomed by u/rsc

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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cantelope

remix of d/2845 by u/cantelope

function u(t) {

A=960,B=540,x.fillRect(0,0,D=2e3,D)
for(i=D;i--;)x.clearRect(A+1/(Z=2.5+C(p=i*C(t/2)/40)*S(q=i/628))*(X=S(p)*S(q))*A,B+C(q)/Z*A,s=69/Z/Z,s)

Jul 10 2017 4:43 AM UTC

}// 140/140

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Show more comments…
u/lionleaf

That's really neat!
u/Polyducks

This is amazing! What's the concept behind it? How are you getting the sphere?
u/cantelope

@Polyducks, it's a golfed version of the equation of a sphere [x=sin(p1)*sin(p2);z=cos(p2);z=cos(p1)*sin(p2);] combined with a tiny 3D projector, X=cx+1/z*x*cx; Y=cy+y/z*cx, where cx/cy is center screen, and x/y/z are the 3D coordinates. Hope that makes sense! :)
u/cantelope

*equation of a sphere: [x=sin(p1)*sin(p2);y=cos(p2);z=cos(p1)*sin(p2);]
u/alien

thanks for that, is projector a mathematical construct? does it have other names?
u/cantelope

@alien it's my own invention, the product of years of research into geometry. I wrote a tutorial with a (very ungolfed) version here https://cantelope.org/3D
u/alien

*__*
u/alien

All the lienar algebra and vectorial calculus in my bachelor finnally comes to life in my head... this is soooo cool @cantelope...
u/donbright

bravo... bravo

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