#circlechallenge (no sine/cosine) by cantelope

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

function u(t) {

x.fillRect(960+((b=t?b:[0,h=520,h/22.7,0])[0]+=b[2]),h+(b[1]+=b[3]),9,9,b[2]-=b[0]/h,b[3]-=b[1]/h)

Nov 2 2021 12:30 PM UTC

}// 98/140

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#circlechallenge (no sine/cosine)

u/donbright

does fillrect have 6 parameters here?
u/cantelope

heh. it only looks at the first 4. i'm not actually saving any space by including 6 parameters, but why not? :)
u/cantelope

can you see how this circle method works? there is an array with 4 elements, the first 2 being positions (x,y), and the last 2 being analogous to a vector (in physics) with magnitude and direction, or simply (velocity-x, velocity-y). The velocity vector is added to the position coordinates once per frame and is itself adjusted in a way to create a perfectly circular "orbit" about the origin. Interestingly, this approach can be extended into 3 or more dimensions, and involve, obviously, more than 2 bodies. 3-body orbital chaos can be very interesting and beautiful, e.g. https://code.dweet.net/full/2w8z


      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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