class Noise
{
  int xd,yd,xf,yf;
  float increment = 0.02;
  
  Noise(float XD,float YD,float XF,float YF)
  {
    xd=int(XD);
    yd=int(YD);
    xf=int(XF);
    yf=int(YF);
  }
  
  void Dessiner(){
    loadPixels();

    float xoff = 0.0; // Start xoff at 0

      // For every x,y coordinate in a 2D space, calculate a noise value and produce a brightness value
    for (int x = xd; x < xf; x++) {
      xoff += increment;   // Increment xoff 
      float yoff = 0.0;   // For every xoff, start yoff at 0
      for (int y = yd; y < yf; y++) {
        yoff += increment; // Increment yoff

        // Calculate noise and scale by 255
        float bright = noise(xoff,yoff)*255;

        // Try using this line instead
        //float bright = random(0,255);

        // Set each pixel onscreen to a grayscale value
        pixels[x+y*width] = color(bright);
      }
    }

    updatePixels();
  }
}