/* BTW: You can use ANY function as the noise/plasma function * It just needs to return a float in the range 0.0 - 17.0 * But shouldn't return 0.0 or 17.0 (they're exclusive bounds). * View this shader on shadertoy: https://www.shadertoy.com/view/t3tSRj# */ // TODO: go through all my TODO items /* ==== Text Colouring ==== */ #define PHOSPHOR_COL vec4(1, 1., 1., 1.) #define BG_COL vec4(0.2, 0.0, 0.2, 0.) /* ======= Text Size ======= */ #define FONT_SIZE vec2(10.,20.) #define ROWCOLS vec2(80., 24.) /* === Text Bloom Effect === */ #define WIDTH 1.2 #define HEIGHT 0.7 #define SMOOTH 0.004 /* ====== Smoke Noise ====== */ const int noiseSwirlSteps = 0; const float noiseSwirlValue = 1.; const float noiseSwirlStepValue = noiseSwirlValue / float(noiseSwirlSteps); const float noiseScale = 1.0; const float noiseTimeScale = 0.1; precision highp float; // =================================================================== // Library Functions // inline float rand(vec2 co) { return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453); } inline float quantise(float val, float n) { return clamp(floor(val * n), 0.0, n) / n; } inline float roundSquare(vec2 p, vec2 b, float r) { return length(max(abs(p)-b,0.0))-r; } // standard roundSquare inline float stdRS(vec2 uv, float r) { return roundSquare(uv - 0.5, vec2(WIDTH, HEIGHT) + r, 0.05); } // =================================================================== // Description : Array and textureless GLSL 2D/3D/4D simplex // noise functions. // Author : Ian McEwan, Ashima Arts. // Maintainer : ijm // Lastmod : 20110822 (ijm) // License : Copyright (C) 2011 Ashima Arts. All rights reserved. // Distributed under the MIT License. See LICENSE file. // https://github.com/ashima/webgl-noise // inline vec3 mod289(vec3 x) { return x - floor(x * (1.0 / 289.0)) * 289.0; } inline vec4 mod289(vec4 x) { return x - floor(x * (1.0 / 289.0)) * 289.0; } inline vec4 permute(vec4 x) { return mod289(((x*34.0)+1.0)*x); } inline vec4 taylorInvSqrt(vec4 r) { return 1.79284291400159 - 0.85373472095314 * r; } float simplex(vec3 v) { const vec2 C = vec2(1.0/6.0, 1.0/3.0) ; const vec4 D = vec4(0.0, 0.5, 1.0, 2.0); // First corner vec3 i = floor(v + dot(v, C.yyy) ); vec3 x0 = v - i + dot(i, C.xxx) ; // Other corners vec3 g = step(x0.yzx, x0.xyz); vec3 l = 1.0 - g; vec3 i1 = min( g.xyz, l.zxy ); vec3 i2 = max( g.xyz, l.zxy ); vec3 x1 = x0 - i1 + C.xxx; vec3 x2 = x0 - i2 + C.yyy; vec3 x3 = x0 - D.yyy; // Permutations i = mod289(i); vec4 p = permute( permute( permute( i.z + vec4(0.0, i1.z, i2.z, 1.0 )) + i.y + vec4(0.0, i1.y, i2.y, 1.0 )) + i.x + vec4(0.0, i1.x, i2.x, 1.0 )); // Gradients: 7x7 points over a square, mapped onto an octahedron. // The ring size 17*17 = 289 is close to a multiple of 49 (49*6 = 294) float n_ = 0.142857142857; // 1.0/7.0 vec3 ns = n_ * D.wyz - D.xzx; vec4 j = p - 49.0 * floor(p * ns.z * ns.z); // mod(p,7*7) vec4 x_ = floor(j * ns.z); vec4 y_ = floor(j - 7.0 * x_ ); // mod(j,N) vec4 x = x_ *ns.x + ns.yyyy; vec4 y = y_ *ns.x + ns.yyyy; vec4 h = 1.0 - abs(x) - abs(y); vec4 b0 = vec4( x.xy, y.xy ); vec4 b1 = vec4( x.zw, y.zw ); vec4 s0 = floor(b0)*2.0 + 1.0; vec4 s1 = floor(b1)*2.0 + 1.0; vec4 sh = -step(h, vec4(0.0)); vec4 a0 = b0.xzyw + s0.xzyw*sh.xxyy ; vec4 a1 = b1.xzyw + s1.xzyw*sh.zzww ; vec3 p0 = vec3(a0.xy,h.x); vec3 p1 = vec3(a0.zw,h.y); vec3 p2 = vec3(a1.xy,h.z); vec3 p3 = vec3(a1.zw,h.w); //Normalise gradients vec4 norm = taylorInvSqrt(vec4(dot(p0,p0), dot(p1,p1), dot(p2, p2), dot(p3,p3))); p0 *= norm.x; p1 *= norm.y; p2 *= norm.z; p3 *= norm.w; // Mix final noise value vec4 m = max(0.6 - vec4(dot(x0,x0), dot(x1,x1), dot(x2,x2), dot(x3,x3)), 0.0); m = m * m; return 42.0 * dot( m*m, vec4( dot(p0,x0), dot(p1,x1), dot(p2,x2), dot(p3,x3) ) ); } // =================================================================== // VT220 Font Rendering // Author/Source : https://www.shadertoy.com/view/llSXDV // #define l(y,a,b) roundLine(p, vec2(float(a), float(y)), vec2(float(b), float(y))) float roundLine(vec2 p, vec2 a, vec2 b) { b -= a + vec2(1.0,0.); p -= a; float f = length(p-clamp(dot(p,b)/dot(b,b),0.0,1.0)*b); if (iResolution.y < 320.) // attempt to get rid of aliasing on small resolution return smoothstep(1.0, 0.9, f); else if (iResolution.y < 720.) return smoothstep(0.75, 0.5, f); else return smoothstep(1., 0., f); } float vt220Font(vec2 p, float c) { if (c < 1.) return 0.; if (p.y > 16.) { if (c > 2.) return 0.0; if (c > 1.) return l(17,1,9); } if (p.y > 14.) { if (c > 16.) return l(15,3,8); if (c > 15.) return l(15,1,8); if (c > 14.) return l(15,1,3)+ l(15,7,9); if (c > 13.) return l(15,2,8); if (c > 12.) return l(15,1,9); if (c > 11.) return l(15,2,8); if (c > 10.) return l(15,1,3)+ l(15,6,8); if (c > 9.) return l(15,4,6); if (c > 8.) return l(15,2,4)+ l(15,5,7); if (c > 7.) return l(15,2,8); if (c > 6.) return l(15,2,8); if (c > 5.) return l(15,2,8); if (c > 4.) return l(15,2,9); if (c > 3.) return l(15,1,8); if (c > 2.) return l(15,2,9); } if (p.y > 12.) { if (c > 16.) return l(13,2,4)+ l(13,7,9); if (c > 15.) return l(13,2,4)+ l(13,7,9); if (c > 14.) return l(13,1,3)+ l(13,7,9); if (c > 13.) return l(13,1,3)+ l(13,7,9); if (c > 12.) return l(13,1,3); if (c > 11.) return l(13,4,6); if (c > 10.) return l(13,2,4)+ l(13,5,9); if (c > 9.) return l(13,2,8); if (c > 8.) return l(13,2,4)+ l(13,5,7); if (c > 7.) return l(13,1,3)+ l(13,7,9); if (c > 6.) return l(13,1,3)+ l(13,7,9); if (c > 5.) return l(13,1,3)+ l(13,7,9); if (c > 4.) return l(13,1,3)+ l(15,2,9); if (c > 3.) return l(13,1,4)+ l(13,7,9); if (c > 2.) return l(13,1,3)+ l(13,6,9); } if (p.y > 10.) { if (c > 16.) return l(11,1,3); if (c > 15.) return l(11,2,4)+ l(11,7,9); if (c > 14.) return l(11,1,9); if (c > 13.) return l(11,7,9); if (c > 12.) return l(11,2,5); if (c > 11.) return l(11,4,6); if (c > 10.) return l(11,3,5)+ l(11,6,8); if (c > 9.) return l(11,4,6)+ l(11,7,9); if (c > 8.) return l(11,1,8); if (c > 7.) return l(11,1,3)+ l(11,7,9); if (c > 6.) return l(11,1,3)+ l(11,7,9); if (c > 5.) return l(11,1,3)+ l(11,7,9); if (c > 4.) return l(11,1,3); if (c > 3.) return l(11,1,3)+ l(11,7,9); if (c > 2.) return l(11,2,9); } if (p.y > 8.) { if (c > 16.) return l(9,1,3); if (c > 15.) return l(9,2,8); if (c > 14.) return l(9,1,3)+ l(9,7,9); if (c > 13.) return l(9,4,8); if (c > 12.) return l(9,4,8); if (c > 11.) return l(9,4,6); if (c > 10.) return l(9,4,6); if (c > 9.) return l(9,2,8); if (c > 8.) return l(9,2,4)+ l(9,5,7); if (c > 7.) return l(9,1,3)+ l(9,7,9); if (c > 6.) return l(9,1,3)+ l(9,7,9); if (c > 5.) return l(9,1,3)+ l(9,7,9); if (c > 4.) return l(9,1,3)+ l(9,7,9); if (c > 3.) return l(9,1,4)+ l(9,7,9); if (c > 2.) return l(9,7,9); } if (p.y > 6.) { if (c > 16.) return l(7,1,3); if (c > 15.) return l(7,2,4)+ l(7,7,9); if (c > 14.) return l(7,2,4)+ l(7,6,8); if (c > 13.) return l(7,5,7); if (c > 12.) return l(7,7,9); if (c > 11.) return l(7,2,6); if (c > 10.) return l(7,2,4)+ l(7,5,7); if (c > 9.) return l(7,1,3)+ l(7,4,6); if (c > 8.) return l(7,1,8); if (c > 7.) return l(7,2,8); if (c > 6.) return l(7,2,8); if (c > 5.) return l(7,2,8); if (c > 4.) return l(7,2,8); if (c > 3.) return l(7,1,8); if (c > 2.) return l(7,2,8); } if (p.y > 4.) { if (c > 16.) return l(5,2,4)+ l(5,7,9); if (c > 15.) return l(5,2,4)+ l(5,7,9); if (c > 14.) return l(5,3,7); if (c > 13.) return l(5,6,8); if (c > 12.) return l(5,1,3)+ l(5,7,9); if (c > 11.) return l(5,3,6); if (c > 10.) return l(5,1,5)+ l(5,6,8); if (c > 9.) return l(5,2,8); if (c > 8.) return l(5,2,4)+ l(5,5,7); if (c > 7.) return 0.; if (c > 6.) return 0.; if (c > 5.) return 0.; if (c > 4.) return 0.; if (c > 3.) return l(5,1,3); if (c > 2.) return 0.; } if (p.y > 2.) { if (c > 16.) return l(3,3,8); if (c > 15.) return l(3,1,8); if (c > 14.) return l(3,4,6); if (c > 13.) return l(3,1,9); if (c > 12.) return l(3,2,8); if (c > 11.) return l(3,4,6); if (c > 10.) return l(3,2,4)+ l(3,7,9); if (c > 9.) return l(3,4,6); if (c > 8.) return l(3,2,4)+ l(3,5,7); if (c > 7.) return l(3,2,4)+ l(3,6,8); if (c > 6.) return l(3,1,3)+ l(3,4,7); if (c > 5.) return l(3,2,4)+ l(3,6,8); if (c > 4.) return 0.; if (c > 3.) return l(3,1,3); if (c > 2.) return 0.; } else { if (c > 7.) return 0.; if (c > 6.) return l(1,2,5)+ l(1,6,8); } return 0.0; } // =================================================================== // Noise Generation Algorithms // textLines(...) is for simulating the writing of random characters in line formats // https://www.shadertoy.com/view/llSXDV (same author as VT220 font rendering) // // smokeNoise(...) is for the main noise generation algorithm (very tunable) // https://www.shadertoy.com/view/MsdGWn // float textLines(vec2 uvG) { float wt = 5. * (iTime + 0.5*sin(iTime*1.4) + 0.2*sin(iTime*2.9)); // wobbly time vec2 uvGt = uvG + vec2(0., floor(wt)); float ll = rand(vec2(uvGt.y, - 1.)) * ROWCOLS.x; // line length if (uvG.y > ROWCOLS.y - 2.){ if (ceil(uvG.x) == floor(min(ll, fract(wt)*ROWCOLS.x))) return 2.; if (ceil(uvG.x) > floor(min(ll, fract(wt)*ROWCOLS.x))) return 0.; } if (uvGt.x > 5. && rand(uvGt) < .075) return 0.; if (max(5., uvGt.x) > ll) return 0.; return rand(uvGt)*15. + 2.; } inline float fbm3(vec3 v) { float result = simplex(v); result += simplex(v * 2.) / 2.; result += simplex(v * 4.) / 4.; result /= (1. + 1./2. + 1./4.); return result; } inline float fbm5(vec3 v) { float result = simplex(v); result += simplex(v * 2.) / 2.; result += simplex(v * 4.) / 4.; result += simplex(v * 8.) / 8.; result += simplex(v * 16.) / 16.; result /= (1. + 1./2. + 1./4. + 1./8. + 1./16.); return result; } float smokeNoise(vec3 v) { // make it curl for (int i=0; i