Hi guys, im having a bit of trouble with getting this grid to generate a new randomised colour for each cell on mousePressed. Ive got it working initally and i though that since the randomcolor() function is being called in setup, calling setup() again should provide a new set of randomised colors. Its not working so well.

Cell[][] grid;  // 2D Array of objects

int cols = 30;  // Number of columns and rows in the grid
int rows = 30;

void setup() {
  size(300, 300);
  grid = new Cell[cols][rows];

  for (int i = 0; i < cols; i ++ ) {
    for (int j = 0; j < rows; j ++ ) {
      grid[i][j] = new Cell(i*10, j*10, 10, 10, i + j);
      grid[i][j].display();
    }
  }
}


//void draw() {
//}


void keyPressed() {
  for (int i = 0; i < cols; i ++ ) {
    for (int j = 0; j < rows; j ++ ) {
      grid[i][j].key();
      setup();
    }
  }
}

And heres Cell Object

class Cell {      // Cell object

  float x, y;   // x,y location
  float w, h;   // width and height

  Cell(float tempX, float tempY, float tempW, float tempH, float tempAngle) { // Cell Constructor
    x = tempX;
    y = tempY;
    w = tempW;
    h = tempH;
  }


  void randomcolor() {          //Function to randomise colour
    fill(random(255), random(255), random(255));
  }


  void display() {
    stroke(0);
    randomcolor();
    rect(x, y, w, h);
  }

  void colchange() {          //Function to randomise colour
    randomcolor();
  }

  void key() {         
    colchange();
  }
}