Noise Walker Edge Detection

injuvik

Hey guys,

i've created a little random walker-sketch, but i have no idea how to tell the dot to stay inside the canvas. Any suggestions? Thank you !!!

PS: I'm also happy about any kind of advices for better syntax. :-)

Dot dot;

void setup() {
  size(100, 100);
  background(#222222);
  noStroke();
  dot = new Dot();
  fill(#eeeeee);
}

void draw() {
  dot.move();
  dot.display();
}



class Dot {

  int x = width/2;
  int y = height/2;
  float xoff =100;
  float yoff = 200;
  int xspeed;
  int yspeed;


  void move() {

    float thenoise1 = noise(xoff);  
    float thenoise2 = noise(yoff);  
    int stepx = int(map(thenoise1, 0, 1, 0, 3))-1; 
    int stepy = int(map(thenoise2, 0, 1, 0, 3))-1; 

    x = x + stepx;
    y = y + stepy;
    xoff = xoff + 0.1;
    yoff = yoff + 0.1;
  }

  void display() {
    ellipse(x, y, 2, 2);
  }
}

injuvik

Is constrain() a good solution? Some thing like

constrain(x,0,width);
constrain(y,0,height);

?

I could not make it work anyway...

TfGuy44

Constrain will certainly do it. But there's a trick to using constrain - it doesn't actually reassign your variable's value! Instead, it returns a constrained value. Thus, you need to do the assignment yourself. Try adding these lines to your class, after changing the Dot's position:

x = constrain(x,0,width);
y = constrain(y,0,height);

injuvik

Works perfect. Thank you!!!

injuvik

Oh i see, there's another thing:

My walker walks to the top left of the canvas, but i want it to have no walking direction-tendency. Any suggestions?

TfGuy44

Make sure your stepx and stepy values are being generated so that, on average, they sum to 0. One way to ensure this is to generate them between 0 and some maximum, and then negate them half the time.

Is there a reason you are using noise() to generate these values, instead of good-old random()?

koogs

Make sure your stepx and stepy values are being generated so that, on average, they sum to 0

i just said this in another thread...multiple questions just confuses things.