// Author @patriciogv - 2015 // http://patriciogonzalezvivo.com #ifdef GL_ES precision mediump float; #endif uniform vec2 u_resolution; uniform float u_time; float random (in float x) { return fract(sin(x)*1e4);} float random (in vec2 st){ return fract(sin(dot(st.xy ,vec2(12.9898,78.233))) * 43758.5453); } float bin(vec2 ipos, float n){ float remain = mod(n,33554432.); for(float i = 0.0; i < 25.0; i++){ if ( floor(i/3.) == ipos.y && mod(i,3.) == ipos.x ) { return step(1.0,mod(remain,2.)); } remain = ceil(remain/2.); } return 0.0; } float char(vec2 st, float n){ st.x = st.x*2.-0.5; st.y = st.y*1.2-0.1; vec2 grid = vec2(3.,5.); vec2 ipos = floor(st*grid); vec2 fpos = fract(st*grid); n = floor(mod(n,10.)); float digit = 0.0; if (n < 1. ) { digit = 31600.; } else if (n < 2. ) { digit = 9363.0; } else if (n < 3. ) { digit = 31184.0; } else if (n < 4. ) { digit = 31208.0; } else if (n < 5. ) { digit = 23525.0; } else if (n < 6. ) { digit = 29672.0; } else if (n < 7. ) { digit = 29680.0; } else if (n < 8. ) { digit = 31013.0; } else if (n < 9. ) { digit = 31728.0; } else if (n < 10. ) { digit = 31717.0; } float pct = bin(ipos, digit); vec2 borders = vec2(1.); // borders *= step(0.01,fpos.x) * step(0.01,fpos.y); // inner borders *= step(0.0,st)*step(0.0,1.-st); // outer return step(.5,1.0-pct) * borders.x * borders.y; } void main(){ vec2 st = gl_FragCoord.st/u_resolution.xy; st.x *= u_resolution.x/u_resolution.y; float rows = 34.0; vec2 ipos = floor(st*rows); vec2 fpos = fract(st*rows); ipos += vec2(0.,floor(u_time*20.*random(ipos.x+1.))); float pct = random(ipos); vec3 color = vec3(char(fpos,100.*pct)); color = mix(color,vec3(color.r,0.,0.),step(.99,pct)); gl_FragColor = vec4( color , 1.0); }