float turtle_x, turtle_y, turtle_angle;
float pen_x, pen_y;
float turtle_scalar;
int place_on_stack;
float[] stack_x;
float[] stack_y; //component of branching stack
float[] stack_angle;
char[] l_string;
String l_str;
String l_list[];
String lexicon[];
String dictionary;
String gen_string[];
float curr_degree;
float counter;
boolean re_draw = false;
boolean animate = false;
float gravity = .5;
float seek_x,seek_y;
float seek_amount;

void setup()
{
  stroke(255,255,255); 
  background(0,0,0);
  gen_string = new String[50];
  l_list = new String[50];
  dictionary = "F - +";
  lexicon = splitStrings(dictionary);
  
  seek_x = 100;
  seek_y = 100;
  seek_amount = 0;
  
  float piece;
  int j;
  for (j = 0; j < 50; j++)
  {
   piece = random(3);
  // l_list[j] = lexicon[(int)piece];
  }
  
  //This is the string to alter to change the shape of the L-System
  l_str = "[ F [ + F F F [ - - F - F + F - F + F ] [ - - F - F + F - F + F [ + + F - F + F - F + F ] [ - - F - F + F - F + F ] ] F - F - F - F - F - F - F ]";
 // l_str = join(gen_string);
  l_list = splitStrings(l_str);
  size(500,500);

  turtle_scalar = 15;
  turtle_angle = 180;
  float rad = radians(turtle_angle);
  turtle_x = cos(rad) * turtle_scalar;
  turtle_y = sin(rad) * turtle_scalar;

  pen_x = width/2;
  pen_y = height/2;

  curr_degree = 0;
      
  place_on_stack = 0;
  stack_x = new float[100];
  stack_y = new float[100];
  stack_angle = new float[100];

  DrawLSystem();
}

void loop()
{
seek_x = mouseX;
seek_y = mouseY;
  checkStuff();
  
  if (animate == true)
  {
  counter += .01;
   float rad = radians(curr_degree);
  rad = sin(counter) * 10;
  curr_degree = degrees(rad); 
  }
  
  if (counter > (3.141592653 * 2))
  {
    counter = 0;
  }
  turtle_scalar = 15;
  turtle_x = 0;
  turtle_y = turtle_scalar;
  turtle_angle = 90;
  
  place_on_stack = 0;

  pen_x = width/2;
  pen_y = height/2;
  


  

  DrawLSystem();
    color white = color(255, 255, 255); 
  set ((int)seek_x,(int)seek_y,white);
}


void DrawLSystem()
{
  int l_length = l_list.length;
  int i;
  float rad;
  
  if (re_draw == true)
  {
    background(0,0,0);
  }

  for (i = 0; i < (l_length - 1); i++)
  {
    if (l_list[i].equals("F"))
    {
    float new_pen_x, new_pen_y;
    new_pen_x = pen_x + turtle_x;
    new_pen_y = pen_y + turtle_y - gravity;
    
    if (new_pen_x < seek_x)
    {
    new_pen_x += seek_amount;
    }
    else
    {
    new_pen_x -= seek_amount;
    }
    
    if (new_pen_y < seek_y)
    {
    new_pen_y += seek_amount;
    }
    else
    {
    new_pen_y -= seek_amount;
    }
    
    //normalize
    float xDiff, yDiff;
    xDiff = new_pen_x - pen_x;
    yDiff = new_pen_y - pen_y;
    float new_length = sqrt((xDiff * xDiff) + (yDiff * yDiff));
    xDiff = xDiff/new_length;
    yDiff = yDiff/new_length;
    
    xDiff *= turtle_scalar;
    yDiff *= turtle_scalar;
     
    
    new_pen_x = pen_x + xDiff;
    new_pen_y = pen_y + yDiff;
    
    
    line(pen_x, pen_y, new_pen_x,new_pen_y);
    pen_x = new_pen_x;
    pen_y = new_pen_y;
      
    }

    if (l_list[i].equals("+"))
    {
      turtle_angle += curr_degree;
      rad = radians(turtle_angle);
      turtle_x = cos(rad) * turtle_scalar;
      turtle_y = sin(rad) * turtle_scalar;
    }

    if (l_list[i].equals("-"))
    {
      turtle_angle -= curr_degree;
      rad = radians(turtle_angle);
      turtle_x = cos(rad) * turtle_scalar;
      turtle_y = sin(rad) * turtle_scalar;
    }
    
    if (l_list[i].equals("[")) //push
    {
      stack_x[place_on_stack] = pen_x;
      stack_y[place_on_stack] = pen_y;
      stack_angle[place_on_stack] = turtle_angle;
      place_on_stack += 1;
    }
    
     if (l_list[i].equals("]")) //pop
    {
      place_on_stack -= 1;
      pen_x = stack_x[place_on_stack];
      pen_y = stack_y[place_on_stack];
      turtle_angle = stack_angle[place_on_stack];
      
      rad = radians(turtle_angle);
      turtle_x = cos(rad) * turtle_scalar;
      turtle_y = sin(rad) * turtle_scalar;
    }
  }
}

/*void DrawLSystem()
{
  int l_length = l_list.length;
  int i;
  float rad;

  for (i = 0; i < (l_length - 1); i++)
  {
    if (l_list[i].equals("F"))
    {
      line(pen_x,pen_y, pen_x + turtle_x, pen_y + turtle_y);
      pen_x += turtle_x;
      pen_y += turtle_y;
    }

    if (l_list[i].equals("+"))
    {
      turtle_angle += 15;
      rad = radians(turtle_angle);
      turtle_x = cos(rad) * turtle_scalar;
      turtle_y = sin(rad) * turtle_scalar;
    }

    if (l_list[i].equals("-"))
    {
      turtle_angle -= 15;
      rad = radians(turtle_angle);
      turtle_x = cos(rad) * turtle_scalar;
      turtle_y = sin(rad) * turtle_scalar;
    }
    
    if (l_list[i].equals("[")) //push
    {
      stack_x[place_on_stack] = pen_x;
      stack_y[place_on_stack] = pen_y;
      stack_angle[place_on_stack] = turtle_angle;
      place_on_stack += 1;
    }
    
     if (l_list[i].equals("]")) //pop
    {
      place_on_stack -= 1;
      pen_x = stack_x[place_on_stack];
      pen_y = stack_y[place_on_stack];
      turtle_angle = stack_angle[place_on_stack];
      
      rad = radians(turtle_angle);
      turtle_x = cos(rad) * turtle_scalar;
      turtle_y = sin(rad) * turtle_scalar;
    }
  }
}*/

void mouseReleased() 
{ 
  animate = !animate;
} 

void checkStuff()
{
if(keyPressed) { 
    if (key == 'd' || key == 'D') { 
      re_draw = !re_draw;
    } 
    
    if (key == 'a' || key == 'A') { 
      gravity -= 1;
    } 
    
     if (key == 's' || key == 'S') { 
      gravity += 1;
      //if (gravity > 0) gravity = 0;
    } 
    
     if (key == 'z' || key == 'Z') { 
      curr_degree -= 1;
    } 
    
     if (key == 'x' || key == 'X') { 
      curr_degree += 1;
    } 
    
     if (key == 'e' || key == 'E') { 
      seek_amount -= .1;
      if (seek_amount < 0) seek_amount = 0;
    } 
    
     if (key == 'r' || key == 'R') { 
      seek_amount += .1;
    } 
    
    
  } 
}