int stageWidth_int = 566;
int stageHeight_int = 400;
int warmNum_int = 20;

float setting_v;
float setting_raRange;

Warm[] warms_ar = new Warm[20];

void setup(){

  size(566,400); 
  loop();
  
  for(int i=0; i<warmNum_int; i++){
    warms_ar[i] = new Warm(random(0,stageWidth_int),random(0,stageHeight_int));
  }
  setting_v = random(0.1,2);
  setting_raRange = random(0.1,1);
  background(0); 
 setting();
}


void setting(){
  //background(0); 
  
  float x = mouseX;
  float y = mouseY;
  
  float v = random(1,5);
  float rar = random(0.1,2);
  for(int i=0; i<warmNum_int; i++){
    warms_ar[i].setPos(x,y);
    warms_ar[i].setV(v);
    warms_ar[i].setRARange(rar);
  }
}

void draw(){
   for(int i=0; i<warmNum_int; i++){
    warms_ar[i].step();
    warms_ar[i].step();
  }
  //fill(0,0,0,1);
  //rect(0,0,width,height);
}

void mousePressed(){
 setting();
}

void keyPressed(){
  if(key=='c' || key=='C'){
    background(0); 
    setting();
  }
}


class Warm{
  float x, y, v;  //xpos, ypos, speed
  float r, rv, ra;  //rotation rotSpeed rotAccel
  float raRange;
  int colR, colG, colB;  // contains rgb
  
  public Warm(float x, float y){
    this.x = x;
    this.y = y;
    v = 0;
    r = random(0,360);
    rv = 0;
    ra = 0;
    raRange = 0.5;
    
    colR = int(random(50,150));
    colG = int(random(50,150));
    colB = int(random(50,150));
  }
  
  void step(){
    x += cos(r * PI / 180)*v;
    y += sin(r * PI / 180)*v;
    
    x = (x<0)? width: x;
    x = (x>width)? 0: x;
    y = (y<0)? height: y;
    y = (y>height)? 0: y;
    
    ra = ra*0.9 + random(-raRange,raRange);
    rv = rv * 0.99 + ra;
    r += rv;
    
    stroke(color(colR, colG, colB));
    //point(x,y);
    draw();
  }
  
  void setV(float v){
    this.v = v;
  }
  
  void setRARange(float rar){
    this.raRange = rar;
  }
  
  void setPos(float x, float y){
    this.x = x;
    this.y = y;
  }
  
  void draw(){
    /*
    for(int xx=-1; xx<1; xx++){
      for(int yy=-1; yy<1; yy++){
        float d = dist(0,0,xx,yy);
        if(d!=0){
          addPixel(int(x+xx), int(y+yy), color(colR/d, colG/d, colB/d));
        }
      }
    }*/
    addPixel(int(x), int(y), color(colR, colG, colB));
  }
  
  //additive color method()
  void addPixel(int x, int y, color col){
    if (x<0 || x>width-1) return;
    if (y<0 || y>height-1) return;
    color crntCol = get(x, y);
    
    int crntr = crntCol>>16 &0xff;
    int crntg = crntCol>>8 &0xff;
    int crntb = crntCol &0xff;
    int newr = col>>16 &0xff;
    int newg = col>>8 &0xff;
    int newb = col&0xff;
    int setr = int(constrain((crntr + newr)*0.8, 0, 255));
    int setg = int(constrain((crntb + newb)*0.8, 0, 255));
    int setb = int(constrain((crntg + newg)*0.8, 0, 255));
    
    
    set(x,y, color(setr,setg,setb));
    //pixels[5] = color(255,255,255);
  }
}