public void ritaUt() {

    Complex z, hej;
    boolean isInside;
    int antalN = 0;

    background(0);

    for (int i = 0; i < width * height; i++) {
      isInside = true;

      z = toComplex(indexToPixel(i)[0], indexToPixel(i)[1]);

      for (int a = 0; a <= maxIterations; a++) {
        if ((z.getRe() * z.getRe() + z.getIm() * z.getIm()) > 4.0) {
          isInside = false;
          antalN = a;
          break;
        }
        hej = z.mul(z);
        z = hej.add(c);
      }

      if (isInside) {
        stroke(0);
        point(indexToPixel(i)[0], indexToPixel(i)[1]);
      } else {

        // the smmoth fade from black to red to yellow to white to yellow to black.
        if (antalN <= 12) {
          stroke(antalN * 21, 0, 0);
        } else if (antalN <= 24) {
          stroke(252, (antalN - 12) * 21, 0);
        } else if (antalN >= 76) {
          stroke(255 - (antalN - 76) * 7, 140 - (antalN - 76) * 8, 0);
        } else if (antalN >= 40) {
          stroke(252, 252 - (antalN - 40) * 4, 140 - (antalN - 40) * 9);
        } else {
          stroke(255 /*-((antalN-24)/6)*/, 252, (antalN - 24) * 9);
        }

        point(indexToPixel(i)[0], indexToPixel(i)[1]);
      }
    }
  }
 public int[] toCoordinate(Complex punkt) {
   int[] koordinater = {
     (int) (punkt.getRe() * pixelPerRe + (bredd / 2)),
     (int) ((höjd / 2) + (-1 * punkt.getIm() * pixelPerIm))
   };
   return koordinater;
 }
  public void draw() {
    fill(0);
    noStroke();
    rect(0, höjd, bredd, höjd + 21);

    stroke(220);
    fill(230);
    mouse = toComplex(mouseX, mouseY);
    text("      X: " + Math.round(mouse.getRe() * 1000000) / 1000000.0, 5, höjd + 16);
    text("Y: " + Math.round(mouse.getIm() * 1000000) / 1000000.0 + "i", bredd / 2, höjd + 16);
  }
  public void mouseReleased() {

    mouse = toComplex(mouseX, mouseY);

    if (mouseButton == LEFT) {
      background(0);

      minX = (mouse.getRe() - 0.25 * breddZ);
      maxX = (mouse.getRe() + 0.25 * breddZ);
      minY = (mouse.getIm() - 0.25 * höjdZ);
      maxY = (mouse.getIm() + 0.25 * höjdZ);

      // -------

      breddZ = (Math.abs(maxX - minX));
      höjdZ = (Math.abs(maxY - minY));

      pixelPerRe = (double) (bredd / breddZ);
      pixelPerIm = (double) (höjd / höjdZ);

      ritaUt();

    } else if (mouseButton == RIGHT) {
      background(0);

      minX = (mouse.getRe() - 1.5 * breddZ);
      maxX = (mouse.getRe() + 1.5 * breddZ);
      minY = (mouse.getIm() - 1.5 * höjdZ);
      maxY = (mouse.getIm() + 1.5 * höjdZ);
      // -------

      breddZ = (Math.abs(maxX - minX));
      höjdZ = (Math.abs(maxY - minY));

      pixelPerRe = (double) (bredd / breddZ);
      pixelPerIm = (double) (höjd / höjdZ);

      ritaUt();
    }
  }