class AUECHO extends Shader {
  AUECHO() {
    name = "fxAUecho";
    params.add(new Param("mode", 2, new int[]{RANDOM}));
    params.add(new Param("echo", 0, 255, new int[]{SIN, LINE, RAMPUPDOWN, TAN, COS}));
    params.add(new Param("decay", 0, 255, new int[]{SIN, LINE, RAMPUPDOWN, TAN, COS}));
  }
/*
  float inc1, inc2;
  void animate() {
    inc1+=.00003;
    inc2+=.04;
    params.get(1).setValue((sin(inc1)+1)/4);
    params.get(2).setValue((sin(inc2)+1)/2);
    if (random(1) > .99) {
      for (int i = 0; i < params.size(); i++)  
        params.get(i).randomize();
    }
  }
  */
  void apply() {
    renderer.beginDraw();
    if (params.get(0).value == 0) {
      renderer.colorMode(HSB);
      colorMode(HSB);
    } else {
      renderer.colorMode(RGB);
      colorMode(RGB);
    }
    renderer.loadPixels();
    float _delay = map(params.get(1).getValue(params.get(1).value, true), 0, 1, 0.001, 1.0);
    float decay = map(params.get(2).getValue(params.get(2).value, true), 0, 1, 0.0, 1.0);
    int delay = (int)(renderer.pixels.length * _delay);
    color[] history = new color[renderer.pixels.length];
    int blendMode = BLEND;
    for ( int i = 0, l = renderer.pixels.length; i<l; i++) {
      history[i] = renderer.pixels[i];
    }
    for ( int i = 0, l = renderer.pixels.length; i<l; i++) {
      int fromPos = i-delay < 0 ? l-abs(i-delay) : i-delay;
      color fromColor = history[fromPos];
      float r = red(fromColor) * decay;
      float g = green(fromColor) * decay;
      float b = blue(fromColor) * decay;
      color origColor = history[i];
      color toColor = color(
        r = r + red(origColor) > 255 ? r + red(origColor) - 255 : r + red(origColor), // simulate overflow ;)
        g = g + green(origColor) > 255 ? g + green(origColor) - 255 : g + green(origColor), 
        b = b + blue(origColor) > 255 ? b + blue(origColor) - 255 : b + blue(origColor)  );

      renderer.pixels[i] = history[i] = toColor; //blendColor(origColor, toColor, blendMode);
    }
    renderer.updatePixels();
    if (params.get(0).value == 0) {
      renderer.colorMode(RGB);
      colorMode(RGB);
    }
    renderer.endDraw();
  }
}