f, 0.000000f ), // 740 nm\\n vec3( 0.000251f, 0.000098f, 0.000000f ), // 750 nm\\n vec3( 0.000126f, 0.000050f, 0.000000f ), // 760 nm\\n vec3( 0.000065f, 0.000025f, 0.000000f ), // 770 nm\\n vec3( 0.000033f, 0.000013f, 0.000000f ), // 780 nm\\n vec3( 0.000018f, 0.000007f, 0.000000f ), // 790 nm\\n vec3( 0.000009f, 0.000004f, 0.000000f ), // 800 nm\\n vec3( 0.000005f, 0.000002f, 0.000000f ), // 810 nm\\n vec3( 0.000003f, 0.000001f, 0.000000f ), // 820 nm\\n vec3( 0.000002f, 0.000001f, 0.000000f ) // 830 nm\\n);\\n\\nconst xyz_to_rgb = mat3x3f(\\n 3.2404542,-0.9692660, 0.0556434,\\n -1.5371385, 1.8760108,-0.2040259,\\n -0.4985314, 0.0415560, 1.0572252\\n);\\n\\nfn rot(a: float) -> mat2x2f{ return mat2x2f(cos(a), -sin(a),sin(a), cos(a));}\\n\\nfn rotX(a: float) -> mat3x3f{\\n let r = rot(a); return mat3x3f(1.,0.,0.,0.,r[0][0],r[0][1],0.,r[1][0],r[1][1]);\\n}\\nfn rotY(a: float) -> mat3x3f{\\n let r = rot(a); return mat3x3f(r[0][0],0.,r[0][1],0.,1.,0.,r[1][0],0.,r[1][1]);\\n}\\nfn rotZ(a: float) -> mat3x3f{\\n let r = rot(a); return mat3x3f(r[0][0],r[0][1],0.,r[1][0],r[1][1],0.,0.,0.,1.);\\n}\\n\\nfn hash_u(_a: uint) -> uint {\\n var a = _a;\\n a ^= a >> 16;\\n a *= 0x7feb352du;\\n a ^= a >> 15;\\n a *= 0x846ca68bu;\\n a ^= a >> 16;\\n return a;\\n}\\n\\nfn rand() -> float {\\n var s = hash_u(seed);\\n seed = s;\\n return float( s ) / float( 0xffffffffu ); \\n}\\n\\nfn rand_vec2() -> vec2 {\\n return vec2(rand(), rand()); \\n}\\n\\nfn rand_vec3() -> vec3 {\\n return vec3(rand(), rand(), rand()); \\n}\\n\\n// wavelength\\nfn wl_to_xyz(wl: f32) -> vec3 {\\n let x = (wl - 390.0) * 0.1;\\n let index = u32(x);\\n if(index < 0 || index >= SPECTRUM_LEN-1) \\n {\\n return vec3(0.0);\\n }\\n\\n return mix(spectrum[index], spectrum[index+1], fract(x));\\n}\\n\\n\\nfn lens(_p: vec2, z: f32, wl: f32) -> vec2 {\\n let wl_d = (wl - 600.0) / 200.0;\\n\\n var p = _p;\\n\\n let d = dot(p, p);\\n\\n let r_sq = rand();\\n let r = sqrt(r_sq);\\n\\n let o = 1.-sqrt(1-r_sq);\\n\\n let focus = 2.*z - 0.1*d + 0.25*o - 0.1*wl_d;\\n var dof_size = 0.1 * focus;\\n\\n let a = TWO_PI * rand();\\n var c = dof_size * r * vec2(cos(a), sin(a));\\n\\n let coma = 1.5 - 1.5 * wl_d;\\n p += coma * (p*dot(c,c) + c*dot(p,c));\\n\\n let curv = -0.05 + 0.01 * wl_d;\\n p += curv * (c*dot(p,p) + 2*p*dot(p,c));\\n\\n p += c;\\n\\n p /= sqrt(1. + 0.12 * dot(p,p));\\n\\n return p;\\n}\\n\\n#storage hist array, 3>, SCREEN_HEIGHT>, SCREEN_WIDTH>\\n\\n#workgroup_count Splat 4096 1 1\\n@compute @workgroup_size(D_COUNT, 1, 1)\\nfn Splat(@builtin(global_invocation_id) id: uint3) {\\n let res = uint2(textureDimensions(screen));\\n let res_f = vec2(res);\\n let aspect = f32(res.y) / f32(res.x);\\n\\n let mpos = (vec2(mouse.pos) - 0.5*res_f)/res_f.y;\\n\\n // seed = id.x + u32(time.elapsed * 15675416.);\\n seed = id.x;\\n\\n let time = 420.0 + time.elapsed + rand()/30.;\\n\\n\\n let wl = 390.0 + 440 * rand();\\n let wl_x = (wl - 600.) / 200.0;\\n\\n let col = wl_to_xyz(wl);\\n\\n var p = vec3(0., 0.2, 0.);\\n // var p = rand_vec3();\\n\\n let iters = 160;\\n for(var i = 0; i < iters; i++){ \\n\\n let r = rand() + 0.22*wl_x;\\n\\n\\n if(r<0.33){\\n p += vec3(0.1, 0.1*sin(0.2*time), 0.);\\n p *= rotZ(1.8);\\n let d = dot(p, p);\\n p += 0.05*sin(0.168 + 0.012*time + p*2.75 )/(1. + d);\\n p *= 0.98;\\n } else if(r<0.75){\\n p += vec3(0.3,-0.1,0.1 );\\n p *= rotX(1.8);\\n p *= 0.5 ;\\n\\n } else {\\n p += vec3(0.1,0.1,0.1);\\n\\n var k = rand() + wl_x;\\n k *= pow(max(0., sin(0.1*time)), 20.0);\\n p *= rotZ(0.6 + k);\\n\\n p *= 1. + 0.2*sin(0.012*time) ;\\n\\n var d = max(2.0, dot(p,p));\\n p /= d;\\n

@compute.toys