/* 
Part of the ReCode Project (http://recodeproject.com)
Based on "Traveling Through the Square Series" by Roger Coqart
Originally published in "Computer Graphics and Art" v1n3, 1976
Copyright (c) 2015 Ciaron Linstead - OSI/MIT license (http://recodeproject/license).
*/

/* @pjs pauseOnBlur="true"; */

/*
http://recodeproject.com/artwork/v1n3traveling-through-the-square-series
*/

int prob = 8; // 1 to 11

void setup() {
  
  size(1200, 800);
  background(255);
  
  int hcells=width/100; // number of cells in x direction
  int vcells=height/100; // number of cells in y direction

  ArrayList<Line> lines = new ArrayList<Line>();

  for (int y=0; y<=height; y+=height/vcells) {
    for (int x=0; x<=width; x+=width/hcells) {
       
       /* HANDLE IMAGE EDGES */
       // top and bottom edges:
       if (y==0 || y>(height-height/vcells)) {
         lines.add(new Line(x, y, x+width/hcells, y));
       }
      
       // left and right edges:
       if (x==0 || x>(width-width/hcells)) {
         lines.add(new Line(x, y, x, y+height/vcells));
       }
       /* END HANDLE IMAGE EDGES */
       
       // what we want is a 1 in 4 chance of each of top, left, left-diag, right-diag:
       if ((random(1,11)) <= prob)
         lines.add(new Line(x,y,x+width/hcells, y+height/vcells));
       if ((random(1,11)) <= prob)
         lines.add(new Line(x+width/hcells, y, x, y+height/vcells));
       if ((random(1,11)) <= prob)
         lines.add(new Line(x, y, x, y+height/vcells));
       if ((random(1,11)) <= prob)
         lines.add(new Line(x, y, x+width/hcells, y));
    }
  }
  
  for (Line line : lines) {
    line.drawOuter();
  }
  
  for (Line line : lines) {
    line.drawInner();
  }
}

class Line {
  float x1, y1, x2, y2;
  int outerStroke=0;
  int innerStroke=255;
  int outerStrokeWeight=25;
  int innerStrokeWeight=8;
  
  Line(float x1_, float y1_, float x2_, float y2_) {
    x1=x1_;
    x2=x2_;
    y1=y1_;
    y2=y2_;
  }
  
  void drawOuter() {
    stroke(outerStroke);
    strokeWeight(outerStrokeWeight);
    line(x1, y1, x2, y2);
  }
  
  void drawInner() {
    stroke(innerStroke);
    strokeWeight(innerStrokeWeight);
    line(x1, y1, x2, y2);
  } 
}