yonatan

#version 460

/********************************************************************************************************************

Speculative Raymarching

Shaders run code in "waves" or "subgroups" of 32 or 64 threads (or 4 in WebGPU on my box, which is why there's no
web demo for this). The idea here is that instead of 32 pixels running the same (expensive) sdf function which is
likely to return similar results to advance their respective rays - they all band together and cooperatively march
a cone that is large enough to hold all of them.

yonatan

// r = probably screen resolution, o = output color, g = ray depth into the scene
// FC.xy = which pixel we are on
float i,e,f,s,g,k=.01;
for(o++;i++<100;){// go upto 100 steps with the ray
    s=2.;
    vec3 p = vec3((FC.xy-r/s)/r.y*g, g-s); // defining ray direction
    p.yz *= rotate2D(-.8); // rotate the camera/ray downwards
    p.z += t;// fly forward over time
    e=f=p.y
    // compute the terrain height and fog density at this xz coordinate

yonatan

// Commented version of https://twitter.com/zozuar/status/1441384708441456651
// Google-translated (with some editing) from @gam0022's version

float i, // Ray marching loop counter
e, // Volume density (the smaller the value, the higher the density)
s, // FBM scale (and loop counter)
g, // Ray's distance (also used for tunnel twirl and camera prespective)
k = .01; // Handy constant

// Ray marching loop

yonatan

// This is Twigl's "geekest mode" so the code runs inside a "main" function.
// FC.xy is fragcoord
// r.xy is resolution
// t is time (in seconds I think)
// o.rgba is output color

// This is the original code, before any readability improvements:
/*

  #define X(S,D)I=ivec3(S);D=fract(float(I.x^I.y^I.z)*PI

yonatan

/*
 * 
 * Twigl geekest mode 300 es shim for CapJS (no mouse, sound or backbuffer support!)
 * 
 * To render long videos for twitter:
 * 
 * - Paste this into http://capjs.3d2k.com/
 * - Scroll to the bottom and paste your twigl code
 * - Set resolution, time, format (webm), etc.
 * - Capture

yonatan

#!/bin/bash -e
if [[ $# -ne 2 ]]; then
    echo "Usage: swf-surgery <input-file> <output-file>"
    exit 1
fi

TMP="/tmp/$(basename $0).$$"
SWF="$TMP.swf"
BAK="$TMP.\$wf"

yonatan

    var null::no name()::void
    maxStack:2 localCount:5 initScopeDepth:10 maxScopeDepth:10
        pushundefined   ; 1 item on stack
        coerce_a        
        setlocal1       ; 0 items on stack
        pushundefined   ; 1 item on stack
        coerce_a        
        setlocal2       ; 0 items on stack
        pushundefined   ; 1 item on stack
        coerce_a