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base64 is embarrassingly parallel. So just pipe it to the GPU:

  precision highp float;
  uniform vec2 size;
  uniform sampler2D src,tab;
  void main(){
    vec4 a=(gl_FragCoord-.5)*3.,i=vec4(0,1,2,0)+a.y*size.x+a.x,y=floor(i/size.x),x=i-y*size.x;
    #define s(n)texture2D(src,vec2(x[n],y[n])/size)[0]
    #define e(n)texture2D(tab,vec2(a[n],0))[0]
    a=vec4(s(0),s(1),s(2),0)*255.*pow(vec4(2),-vec4(2,4,6,0)),a=fract(a).wxyz+floor(a)/64.,gl_FragColor=vec4(e(0),e(1),e(2),e(3));
  }




HN user: Ah yes let me casually scribble down a tweet-sized base64 encoder that runs parallel on GPU.

Bravo, that is a thing of beauty.

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Uhhh no, it's a huge net loss because the cost of sending it to the GPU and back greatly exceeds the cost of just doing it then and there in CPU; even on iGPU the kernel launch latency etc will kill it, and that's assuming the kernel build is free. Not to mention this is doing pow calls (!!), which is so ridiculous it makes me wonder if this was a kneejerk AI prompt.

Another post in this thread mentioned V8 sped this up by removing a buffer copy; this is adding two buffer copies, each about an order of magnitude slower.

Come on guys...

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Don't make me upload my web-browser-in-a-GLSL-shader snippet

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Uhhh, go for it? You're welcome to link anything you like of course, but do you maybe want to address my actual points if you have any objections? Let's do some measurements, it sounds like you might be surprised by the outcome.

Web browser in a shader also sounds extremely inefficient, for obvious fundamental reasons.

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Sorry, I was cracking a joke about the browser in a shader.

The GLSL I originally posted is from the "cursed mode" of my side project, and I use it to produce a data URI of every frame, 15 times per second, as a twisted homage to old hardware. (No, I didn't use AI :P )

https://github.com/Rezmason/excel_97_egg

That said, is `pow(vec4(2),-vec4(2,4,6,0))` really so bad? I figured it'd be replaced with `vec4(0.25, 0.0625, 0.015625, 1.0)`.

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