import java.applet.*; 
import java.awt.*; 
import java.awt.image.*; 
import java.awt.event.*; 
import java.io.*; 
import java.net.*; 
import java.text.*; 
import java.util.*; 
import java.util.zip.*; 

public class worms10 extends BApplet {
//
//
// My degree was in sculpture, so cut me some slack.
// Code is far from optimal.  Any suggestions? robert@flight404.com
//
// Generic Inverse Kinematic Segmented Worms
// Spacebar toggles draw mode.

// Worm( total segments, waveSize, increment, red, green, blue)
Worm w1 = new Worm(120, 4, .04f, 0, 0, 0);
Worm w2 = new Worm(120, 6, .06f, 0, 0, 0);
Worm w3 = new Worm(120, 8, .08f, 0, 0, 0);
Worm w4 = new Worm(120, 10, .10f, 0, 0, 0);
Worm w5 = new Worm(120, 12, .11f, 0, 0, 0);
Worm w6 = new Worm(120, 14, .12f, 0, 0, 0);
Worm w7 = new Worm(120, 16, .13f, 0, 0, 0);
Worm w8 = new Worm(120, 18, .14f, 0, 0, 0);
Worm w9 = new Worm(120, 20, .15f, 0, 0, 0);
Worm w10 = new Worm(120, 22, .16f, 0, 0, 0);

Meander m1 = new Meander();

boolean clear = true;

void setup() {
  size(600,600);
  noBackground();
  noStroke();
  fill(0,0,0);
  rect(0,0,width,height);
  ellipseMode(CENTER_DIAMETER);
}
 
void loop() {
  drawState();

  w1.wriggle();
  w2.wriggle();
  w3.wriggle();
  w4.wriggle();
  w5.wriggle();
  w6.wriggle();
  w7.wriggle();
  w8.wriggle();
  w9.wriggle();
  w10.wriggle();

  
  m1.move();
} 

void drawState(){
  if (clear){
    fill(255,255,255);
    noStroke();
    rect(0,0,width,height);
  }
}

void keyReleased () {
  if (key == ' ' && clear) { 
    clear = false;
  } else if (key == ' ' && !clear) {
    clear = true;
  }
}

class Meander {
  float left = 50, right = 550, bottom = 50, top = 550;
  float xMax = 6, yMax = 6;
  float xPos = -10, yPos = 300;
  float xLimit, yLimit, xSpeed, ySpeed, xDelta, yDelta;
  
  Meander (){}
  
  void move(){
    if (mousePressed){
      left = mouseX;
      right = mouseX;
      bottom = mouseY;
      top = mouseY;
    } else {
      left = 50;
      right = 550;
      bottom = 50;
      top = 550;
    }
  
  
    if (xPos < left){
      xDelta = random(0,1);
    } else if (xPos > right){
      xDelta = random (-1,0);
    } else {
      xDelta = random(-1,1);
    }
    
    if (yPos < bottom){
      yDelta = random(0,1);
    } else if (yPos > top){
      yDelta = random (-1,0);
    } else {
      yDelta = random(-1,1);
    }
    
    xSpeed = xSpeed + xDelta;
    ySpeed = ySpeed + yDelta;
    
    if (xSpeed > xMax){
      xSpeed = xMax;
    } else if (xSpeed < -xMax){
      xSpeed = -xMax;
    }
    
    if (ySpeed > yMax){
      ySpeed = yMax;
    } else if (ySpeed < -yMax){
      ySpeed = -yMax;
    }

    xPos = xPos + xSpeed;
    yPos = yPos + ySpeed;
  }
}     

class Worm {
  int total = 120;
  float counter = 1;                 // counter for sine wave offset
  float increment;                   // increment for counter for sine wave offset
  float waveSize;                    // wave size for sine wave offset
  float[] dist = new float[total];   // array for distance between points
  float[] xPos = new float[total];   // array for x positions
  float[] yPos = new float[total];   // array for y positions
  float xpd, xpd2, ypd, ypd2;        // variables for movePoints()
  float acceleration = .5f;
  float friction = .5f;
  float cr,cg,cb;

  float dx, dy, d;                   // variables for IK within setPoints()
  float xp=300, yp=300, xp2, yp2;    // variables for elasticity()
  
  Worm (int numOfSegments, float ws, float inc, float r, float g, float b) {
    total = numOfSegments;
    waveSize = ws;
    increment = inc;
    cr = r;
    cg = g;
    cb = b;
  }

  void wriggle(){
    elasticity();
    movePoints();
    pushArray();
    setPoints();
    drawLine();
  }

  void elasticity(){
    xp2 = xp2 * acceleration + (m1.xPos - xp) * friction;
    yp2 = yp2 * acceleration + (m1.yPos - yp) * friction;
    xp = xp + xp2;
    yp = yp + yp2;
  }
  
  void movePoints(){
    for (int i=1; i<=total-1; i++){
      xpd2 = xpd2 * acceleration + (xPos[i] - xPos[i-1]) * friction;
      ypd2 = ypd2 * acceleration + (yPos[i] - yPos[i-1]) * friction;
      xpd = xpd + xpd2;
      ypd = ypd + ypd2;
      xPos[i] = xpd;
      yPos[i] = ypd;
    }
  }

  void pushArray(){
    for (int i=total-2; i>total/2; i--){
      dist[i+1] = dist[i]*.94f;
    }
    for (int i=total/2; i>0; i--){
      dist[i+1] = dist[i]*1.02f;
    }
    dist[1] = sin(counter) * 2 + 3;
    counter = counter + increment;
  }

  void setPoints(){
    xPos[0] = xp;
    yPos[0] = yp;
    for (int i=1; i<total; i++){
      dx = xPos[i] - xPos[i-1];
      dy = yPos[i] - yPos[i-1];
      d = sqrt(sq(dx) + sq(dy));

      xPos[i] = xPos[i-1] + dx * (dist[i]) / d;
      yPos[i] = yPos[i-1] + dy * (dist[i]) / d;
    }
  }
  
  void drawLine(){
    for (int i=total-1; i>20; i--){
      fill((cr/total) * (total-i),0,0);
      ellipse(xPos[i], yPos[i], ((dist[i]*3.5f)/total) * (total - i), ((dist[i]*3.5f)/total) * (total - i));

    }
  }
} 

}