changes to simulate examples

java/examples/Topics/Simulate/SimpleParticleSystem/Particle.pde

@@ -1,67 +1,44 @@
 // A simple Particle class
 
 class Particle {
-  PVector loc;
-  PVector vel;
-  PVector acc;
-  float r;
-  float timer;
-  
-  // Another constructor (the one we are using here)
+  PVector location;
+  PVector velocity;
+  PVector acceleration;
+  float lifespan;
+
   Particle(PVector l) {
-    acc = new PVector(0,0.05,0);
-    vel = new PVector(random(-1,1),random(-2,0),0);
-    loc = l.get();
-    r = 10.0;
-    timer = 100.0;
+    acceleration = new PVector(0,0.05);
+    velocity = new PVector(random(-1,1),random(-2,0));
+    location = l.get();
+    lifespan = 255.0;
   }
 
   void run() {
     update();
-    render();
+    display();
   }
 
   // Method to update location
   void update() {
-    vel.add(acc);
-    loc.add(vel);
-    timer -= 1.0;
+    velocity.add(acceleration);
+    location.add(velocity);
+    lifespan -= 1.0;
   }
 
   // Method to display
-  void render() {
-    ellipseMode(CENTER);
-    stroke(255,timer);
-    fill(100,timer);
-    ellipse(loc.x,loc.y,r,r);
-    displayVector(vel,loc.x,loc.y,10);
+  void display() {
+    stroke(255,lifespan);
+    fill(255,lifespan);
+    ellipse(location.x,location.y,8,8);
   }
   
   // Is the particle still useful?
-  boolean dead() {
-    if (timer <= 0.0) {
+  boolean isDead() {
+    if (lifespan < 0.0) {
       return true;
     } else {
       return false;
     }
   }
-  
-   void displayVector(PVector v, float x, float y, float scayl) {
-    pushMatrix();
-    float arrowsize = 4;
-    // Translate to location to render vector
-    translate(x,y);
-    stroke(255);
-    // Call vector heading function to get direction (note that pointing up is a heading of 0) and rotate
-    rotate(v.heading2D());
-    // Calculate length of vector & scale it to be bigger or smaller if necessary
-    float len = v.mag()*scayl;
-    // Draw three lines to make an arrow (draw pointing up since we've rotate to the proper direction)
-    line(0,0,len,0);
-    line(len,0,len-arrowsize,+arrowsize/2);
-    line(len,0,len-arrowsize,-arrowsize/2);
-    popMatrix();
-  } 
-
 }
 

java/examples/Topics/Simulate/SimpleParticleSystem/ParticleSystem.pde

@@ -2,49 +2,26 @@
 // An ArrayList is used to manage the list of Particles 
 
 class ParticleSystem {
+  ArrayList<Particle> particles;
+  PVector origin;
 
-  ArrayList particles;    // An arraylist for all the particles
-  PVector origin;        // An origin point for where particles are born
-
-  ParticleSystem(int num, PVector v) {
-    particles = new ArrayList();              // Initialize the arraylist
-    origin = v.get();                        // Store the origin point
-    for (int i = 0; i < num; i++) {
-      particles.add(new Particle(origin));    // Add "num" amount of particles to the arraylist
-    }
-  }
-
-  void run() {
-    // Cycle through the ArrayList backwards b/c we are deleting
-    for (int i = particles.size()-1; i >= 0; i--) {
-      Particle p = (Particle) particles.get(i);
-      p.run();
-      if (p.dead()) {
-        particles.remove(i);
-      }
-    }
+  ParticleSystem(PVector location) {
+    origin = location.get();
+    particles = new ArrayList<Particle>();
   }
 
   void addParticle() {
     particles.add(new Particle(origin));
   }
-  
-    void addParticle(float x, float y) {
-    particles.add(new Particle(new PVector(x,y)));
-  }
 
-  void addParticle(Particle p) {
-    particles.add(p);
-  }
-
-  // A method to test if the particle system still has particles
-  boolean dead() {
-    if (particles.isEmpty()) {
-      return true;
-    } else {
-      return false;
+  void run() {
+    Iterator<Particle> it = particles.iterator();
+    while (it.hasNext()) {
+      Particle p = it.next();
+      p.run();
+      if (p.isDead()) {
+        it.remove(); 
+      }
     }
   }
-
 }
-

java/examples/Topics/Simulate/SimpleParticleSystem/SimpleParticleSystem.pde

@@ -11,16 +11,15 @@
 ParticleSystem ps;
 
 void setup() {
-  size(640, 360);
-  colorMode(RGB, 255, 255, 255, 100);
-  ps = new ParticleSystem(1, new PVector(width/2,height/2,0));
+  size(640,360);
+  smooth();
+  ps = new ParticleSystem(new PVector(width/2,50));
 }
 
 void draw() {
   background(0);
+  ps.addParticle();
   ps.run();
-  ps.addParticle(mouseX,mouseY);
 }
 
 
-