lighthouse theme

wavegl02.glsl

float PI = acos(-1.0);

float tone(float t, float freq) {
  return cos(PI * t * freq) * 1.0;
}
float sinunit(float t, float f) {
  return (sin(t*f) + 1.0) / 2.0;
}
float dsp(float t) {
  float f = 0.0;
  float zbar = floor( fract(t/32.0) * 8.0 );
  float bar = floor( fract(t/16.0) * 4.0 );
  float s = floor( fract(t) * 4.0 );
  float st = floor( fract(t/8.0) * 4.0 );

  float q = 220.0;
  f = tone(t, q * (s+1.0)) * (sinunit(t, 2.0)*0.1 + 0.2) * 0.4;
  if (bar > 1.0) {
    f += tone(t, q * ((4.0-st)+1.0) * 2.0) * (sinunit(t, 0.5) * 0.1 + 0.1) * 0.3;
  }
  if (bar > 2.0) {
    f += tone(t, q * ((4.0-st)+1.0) * 3.0) * (sinunit(t, 2.0) * 0.1 + 0.1) * 0.2;
  }
  if (zbar > 4.0) {
    f += tone(t, q * (st+1.0) * 4.0) * (sinunit(t, 10.0)*0.1 + 0.2) * 0.1;
  }

  return f;
}