Shader #2

#ifdef GL_ES
precision mediump float;
#endif


uniform vec2 u_resolution;
uniform vec2 u_mouse;
uniform float u_time;

vec3 colorA = vec3(0.,0.373,0.451);
vec3 colorB = vec3(0.039,0.576,0.588);

float plot (vec2 st, float pct){
  return  step( pct-0.234, st.x) -
          step( pct+0.018, st.x);
}

void main() {
    vec2 st = gl_FragCoord.xy/u_resolution.xy;
    vec3 color = vec3(0.0);

    vec3 pct = vec3(st.y);

 //Build pattern
    pct.g += cos(st.x*sin(u_time/5.0)*25.0) + cos(st.y*sin(u_time/30.0)*15.0);
    pct.b += sin(st.x*sin(u_time/5.0)*25.0) + sin(st.y*sin(u_time/30.0)*15.0);



    // Plot transition lines for each channel
    color = mix(colorA,colorB,plot(st,pct.g));
    color = mix(color,vec3(1.0),plot(st,pct.b));

    gl_FragColor = vec4(color,1.0);
}