Limited Range Delta Compression - Fit 2… by tomxor

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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tomxor

function u(t) {

for(x=96,i=O='';u='񾈗򔼐򪄊'.charCodeAt(i/2)>>i++%2*5&31;O+=String.fromCharCode(x))x+=u-16;throw O

Sep 22 2019 2:00 AM UTC

}// 93/140

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Limited Range Delta Compression - Fit 200 chars! with extreme limitations :D

u/tomxor

Each char is encoded as 5 bits (fitting 4 into each 20bit surrogate pair), representing the numeric difference between the previous and current ASCII codepoint. Since 5 bits only provides 32 values this is limited to shifting -16 to +15 codepoints each char, this makes it rather challenging to write code with since you can only reach a max of 1/3 of the useful ASCII codepoints at a time.
u/tomxor

Here's the encoder if you are looking for a very contrived adventure: f=(s,x=96,b=16,o='')=>{for(p=0,i=0;i<s.length;){x+=d=s.charCodeAt(i)-x;p|=d+b<<((i%4^2)*5);++i%4?0:p=o+=String.fromCodePoint(p+0x10000)}return o;}; f('helloooworld')
u/tomxor

... don't try this, seriously, you can't even get a for loop started
u/tomxor

#compressor


      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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