ColorLabeler1.pde

//Compatible with Processing 3.
PImage map0;
PGraphics offscreen;
int countDistricts=3;//Must >= 2, obviously.
District[] districts;
Dot[] dots;
Boolean done;
int round=0,frameNum=0;
int lastImageTime;

void setup(){
  map0=loadImage("map.png");//Black shape on whatever background; data/map.png
  map0.loadPixels();
  offscreen=createGraphics(map0.width,map0.height);
  offscreen.noSmooth();
  offscreen.beginDraw();
  offscreen.colorMode(HSB,1);
  offscreen.ellipseMode(RADIUS);
  offscreen.endDraw();
}

void draw(){
  //Initialize districts
  districts=new District[countDistricts];
  for(int district=0;district<countDistricts;district++){
    districts[district]=new District();
  }
  //Initialize dots
  int countDotsImportant=0;
  for(int dot=0;dot<map0.pixels.length;dot++){
    if(map0.pixels[dot]==color(0,0,0)){
      countDotsImportant++;
    }
  }
  dots=new Dot[0];
  for(int dot=0;dot<map0.pixels.length;dot++){
    if(map0.pixels[dot]==color(0,0,0)){
      //dots=(Dot[])append(dots,new Dot(dot%map0.width,dot/map0.width,dots.length%countDistricts));
      if(dots.length<countDotsImportant/countDistricts*countDistricts){
        dots=(Dot[])append(dots,new Dot(dot%map0.width,dot/map0.width,dots.length/(countDotsImportant/countDistricts)));
      }else{
        dots=(Dot[])append(dots,new Dot(dot%map0.width,dot/map0.width,dots.length%countDistricts));
      }
    }
  }
  for(int district=0;district<districts.length;district++){
    println("District "+district+" contains "+districts[district].countDots+" dots.");
  }
  recalc();
  imageDraw();
  //Main loop
  int dot1,dot2;
  int fails=0;
  do{
    round++;
    do{
      dot1=int(random(dots.length));
      dot2=int(random(dots.length));
    }while(dots[dot1].district==dots[dot2].district);
    if(/*dots[dot1].r>districts[dots[dot1].district].r&&dots[dot2].r>districts[dots[dot2].district].r&&*/(dots[dot1].r+dots[dot2].r)/(dots[dot1].rMaybe(dots[dot2].district)+dots[dot2].rMaybe(dots[dot1].district))>1){
      dots[dot1].flipWith(dot2);
      recalc();
      fails=0;
    }else{
      fails++;
    }
    if(millis()-lastImageTime>10*1000||fails>pow(dots.length,1)*pow(districts.length,2)){
      imageDraw();
    }
    if(fails>pow(dots.length,1)*pow(districts.length,2)){
      break;
    }
  }while(true);
  exit();
}

class Dot{
  int x,y;//Coordinates
  int district;//To which this dot belongs
  float r;//From center of district
  Dot(int input0,int input1,int input2){
    x=input0;
    y=input1;
    district=input2;
    r=-1;
    districts[input2].countDots++;
  }
  float rMaybe(int input0){
    return dist(x,y,districts[input0].x,districts[input0].y);
  }
  void flipWith(int input0){
    int temp=dots[input0].district;
    dots[input0].district=district;
    district=temp;
  }
}

class District{
  float x,y;//Coordinates of center
  float r;//Average for all dots
  int countDots;//Number of dots belonging to this district
  District(){
    x=0;
    y=0;
    r=0;
    countDots=0;
  }
}
void recalc(){
  //Calculate district centers, then dot radii, and finally district radii
  for(int dot=0;dot<dots.length;dot++){
    districts[dots[dot].district].x+=dots[dot].x;
    districts[dots[dot].district].y+=dots[dot].y;
  }
  for(int district=0;district<districts.length;district++){
    districts[district].x/=(float)districts[district].countDots;
    districts[district].y/=(float)districts[district].countDots;
  }
  for(int dot=0;dot<dots.length;dot++){
    dots[dot].r=dist(dots[dot].x,dots[dot].y,districts[dots[dot].district].x,districts[dots[dot].district].y);
    districts[dots[dot].district].r+=dots[dot].r;
  }
  for(int district=0;district<districts.length;district++){
    districts[district].r/=(float)districts[district].countDots;
  }
}
void imageDraw(){
  offscreen.beginDraw();
  offscreen.noStroke();
  offscreen.fill(0,0,0);
  offscreen.rect(0,0,offscreen.width,offscreen.height);
  for(int dot=0;dot<dots.length;dot++){
    offscreen.fill((float)dots[dot].district/districts.length,1,1);
    offscreen.rect(dots[dot].x,dots[dot].y,1,1);
  }
  offscreen.stroke(0,0,1);
  offscreen.strokeWeight(1);
  offscreen.noFill();
  for(int district=0;district<districts.length;district++){
    offscreen.ellipse(districts[district].x,districts[district].y,districts[district].r,districts[district].r);
    offscreen.point(round(districts[district].x),round(districts[district].y));
  }
  offscreen.save("output/"+frameNum+".png");
  frameNum++;
  offscreen.endDraw();
  lastImageTime=millis();
}