Pseudo Global Illumination 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

remix of d/28051 by u/tomxor

function u(t) {

eval(unescape(escape`𩡯𬠨𭰽𨰮𭱩𩁴𪀦👩🐱𜀳𝠸𞱩𞱔🐨𜠪𦀦𦠩𙐷🀳𙡙𚡙🀲🱒𛑔🱔𚰮𜀵𞡒𚰽𛠰𝐺𤠡👔🱒𙠽𮀮𩡩𫁬𤡥𨱴𚀭𛑩𙑷𛁩🠾𝰬𜐭𝁥𝐯𚁘𚱙𚰱𞀩𚠪𝐬𜐫𭐥𝠯𝠯𤠩𞠨𭐽𦐼𛠳🱙𚡙𧠲𞡙🀮𝠿𝐺𭰫𦀪𞑞𦐪𝑞𦠪𞐬𥀫𛠱𚐩𦀽𪐥𭰯𝠴𚡒𛑔𛁙👩𛰴𩐳𚡒𛑔𛁚👴𚠳𚱔`.replace(/u../g,'')))

Jun 28 2023 4:47 AM UTC

}// 140/140

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Pseudo Global Illumination

Show more comments…
u/KilledByAPixel

wow!
u/UEZ

brutal
u/Joachim

:O
u/vain

OMFG!!! Absolutly incredible. A "making of" or "how is it done" would be really nice. Awesome work you did!
u/tomxor

Thanks guys :) I have time to outline the pseudo radiance/GI concept at least: Each pixel's ray reflects once after the 1st intersection with the scene. All rays reflect in the same pre-defined direction, in parallel with each other, and roughly towards the light source but not collinear with it i.e not directly in line. The distance between the 2nd intersection (reflected ray end position) and the light source position, is used to estimate luminance.
u/tomxor

This is not physically accurate or intuitive, but is similar in concept to ambient occlusion where single bounce rays are used to estimate luminance based on "exposure" to ambient light. However unlike AC we can only afford a single ray, so we take that single ray and bounce it in a *similar* direction to the light source and see what we hit (what occludes the ray in that direction, which is why we get directional shading). The closer the 2nd intersection is to the light source the greater the luminance should be as a kind of bad proxy of "is exposed to a (probably?) bright surface".
u/tomxor

The reason we don't simply use the length of the reflected portion of the ray, is because although it does yield occlusion effects, the light position is inconsistent and parallel surfaces are flat and unconvincing because the reflected ray lengths are the same. So by making the light source and reflection ray not quite collinear, the distance between those 2nd intersections and the light source follows a gradient for parallel surfaces, causing more convincing shading... At least that's what I think is happening! I doubt this has good scene adaptability though, probably just a demo algorithm :D
u/tomxor

Also for some reason I'm quite happy with /R, super short poor mans anisotropic texture filter :P just fading out and letting lighting take over the further away the surface.
u/vain

Thanks u/tomxor - you really rock 😎
u/lionleaf

Ok, wow that's amazing!
u/iverjo

Incredible
u/jellyedwards

Unbelievable!!
u/cantelope

wat
u/jdspugh

Stunning
u/ugurkilci

I'm not understand! 𩡯𬠨𭰽𨰮𭱩𩁴𪀦👩🐱𜀳𝠸𞱩𞱔🐨𜠪𦀦𦠩𙐷🀳𙡙𚡙🀲🱒𛑔🱔𚰮𜀵𞡒𚰽𛠰𝐺𤠡👔🱒𙠽𮀮𩡩𫁬𤡥𨱴𚀭𛑩𙑷𛁩🠾𝰬𜐭𝁥𝐯𚁘𚱙𚰱𞀩𚠪𝐬𜐫𭐥𝠯𝠯𤠩𞠨𭐽𦐼𛠳🱙𚡙𧠲𞡙🀮𝠿𝐺𭰫𦀪𞑞𦐪𝑞𦠪𞐬𥀫𛠱𚐩𦀽𪐥𭰯𝠴𚡒𛑔𛁙👩𛰴𩐳𚡒𛑔𛁚👴𚠳𚱔 How? Your have unicode generator?
u/majorh5

You can use https://beta.dwitter.net for compressing your code to get it even smaller.


      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)

dwitter.net