Another fake gravity sim. This time, so… by donbright

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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donbright

remix of d/1399 by u/Kalanchoe

function u(t) {

c.width^=0
t?o.push({X:1,Y:1,U:S(t),V:C(t)}):o=[]
o.map(a=>{Q=a.X**2+a.Y**2,a.X+=a.U-=a.X/Q,a.Y+=a.V-=a.Y/Q,x.fillRect(a.X,a.Y,9,9)})

Mar 28 2017 1:45 AM UTC

}// 133/140

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Another fake gravity sim. This time, some particles get slingshotted out of the system, past escape velocity, others teeter on the brink, and others congregate at 0,0. After a while, the screen is full of a bunch of particles leaving, and others coming back in towards the origin.

Show more comments…
u/nonce

your gravity sims are amazing.
u/z3vin

agreed
u/donbright

thanks this site is very inspiring
u/alien

WOW ,Hi what does this mean :D c.width^=0
u/donbright

alien it basically clears the screen to the default width. in detail, i think it is combining "binary xor" with "set equal to", so basically c.width = c.width xor 0, and since anything xored with 0 is itself, its basically setting c.width to itself.
u/donbright

#physics


      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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