anchor.diff:  
   vec4 sample(vec2 co) {
       vec4 sum = vec4(0.0);
  -    vec2 hstep = vec2(0.0015, 0.0);
  -    vec2 vstep = vec2(0.0, 0.0015);
  +    vec2 hstep = vec2(0.0012, 0.0);
  +    vec2 vstep = vec2(0.0, 0.0012);
   
       sum += texture(uFb, vTextureCoord + co);
       sum += texture(uFb, vTextureCoord + co + hstep) * 0.125;
  
positive.code:     float green = sample(vec2( 0.0000, 0.0)).y;
      float blue  = sample(vec2(-0.0003, 0.0)).z;
      
      outcolor.r = mix(0.5 * red, red, wavePos);
      outcolor.g = mix(0.5 * green, green, wavePos);
      outcolor.b = mix(0.5 * blue, blue, wavePos);
  }
  
negative.code:     sum += texture(uFb, vTextureCoord + co - hstep + vstep) * 0.0625;
      sum += texture(uFb, vTextureCoord + co - vstep - vstep) * 0.0625;
  
      return sum / 1.3;
  }
      
  void main(void){
  