new PShape examples

java/examples/Topics/Create Shapes/ParticleSystemPShape/Particle.pde

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+// An individual Particle
+
+class Particle {
+
+  // Velocity
+  PVector velocity;
+  // Lifespane is tied to alpha
+  float lifespan;
+
+  // The particle PShape
+  PShape part;
+  // The particle size
+  float partSize;
+
+  // A single force
+  PVector gravity = new PVector(0, 0.1);
+
+  Particle() {
+    partSize = random(10, 60);
+    // The particle is a textured quad
+    part = createShape(QUAD);
+    part.noStroke();
+    part.texture(sprite);
+    part.normal(0, 0, 1);
+    part.vertex(-partSize/2, -partSize/2, 0, 0);
+    part.vertex(+partSize/2, -partSize/2, sprite.width, 0);
+    part.vertex(+partSize/2, +partSize/2, sprite.width, sprite.height);
+    part.vertex(-partSize/2, +partSize/2, 0, sprite.height);
+    part.end();
+
+    // Set the particle starting location
+    rebirth(width/2, height/2);
+  }
+
+  PShape getShape() {
+    return part;
+  }
+
+  void rebirth(float x, float y) {
+    float a = random(TWO_PI);
+    float speed = random(0.5, 4);
+    // A velocity with random angle and magnitude
+    velocity = PVector.fromAngle(a);
+    velocity.mult(speed);
+    // Set lifespan
+    lifespan = 255;
+    // Set location using translate
+    PVector center = part.getCenter();
+    part.translate(x - center.x, y - center.y);
+  }
+
+  // Is it off the screen?
+  boolean isDead() {
+    PVector center = part.getCenter();
+    if (center.y > height+50) {
+      return true;
+    } 
+    else {
+      return false;
+    }
+  }
+
+  void update() {
+    // Decrease life
+    lifespan = lifespan - 4;
+    // Apply gravity
+    velocity.add(gravity);
+    part.tint(255, lifespan);
+    // Move the particle according to its velocity
+    part.translate(velocity.x, velocity.y);
+  }
+}
+

java/examples/Topics/Create Shapes/ParticleSystemPShape/ParticleSystem.pde

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+// The Particle System
+
+class ParticleSystem {
+  // It's just an ArrayList of particle objects
+  ArrayList<Particle> particles;
+
+  // The PShape to group all the particle PShapes
+  PShape particleShape;
+
+  ParticleSystem(int n) {
+    particles = new ArrayList<Particle>();
+    // The PShape is a group
+    particleShape = createShape(GROUP);
+
+    // Make all the Particles
+    for (int i = 0; i < n; i++) {
+      Particle p = new Particle();
+      particles.add(p);
+      // Each particle's PShape gets added to the System PShape
+      particleShape.addChild(p.getShape());
+    }
+  }
+
+  void update() {
+    for (Particle p : particles) {
+      p.update();
+    }
+  }
+
+  void setEmitter(float x, float y) {
+    for (Particle p : particles) {
+      // Each particle gets reborn at the emitter location
+      if (p.isDead()) {
+        p.rebirth(x, y);
+      }
+    }
+  }
+
+  void display() {
+    shape(particleShape);
+  }
+}
+

java/examples/Topics/Create Shapes/ParticleSystemPShape/ParticleSystemPShape.pde

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+/**
+ * ParticleSystemPShape
+ * 
+ * A particle system optimized for drawing using PShape
+ */
+
+// Particle System object
+ParticleSystem ps;
+// A PImage for particle's texture
+PImage sprite;  
+
+void setup() {
+  size(640, 360, P3D);
+  // Load the image
+  sprite = loadImage("sprite.png");
+  // A new particle system with 10,000 particles
+  ps = new ParticleSystem(10000);
+
+  // Writing to the depth buffer is disabled to avoid rendering
+  // artifacts due to the fact that the particles are semi-transparent
+  // but not z-sorted.
+  hint(DISABLE_DEPTH_MASK);
+
+} 
+
+void draw () {
+  background(0);
+  // Update an dipsplay system
+  ps.update();
+  ps.display();
+  
+  // Set the particle system's emitter location to the mouse
+  ps.setEmitter(mouseX,mouseY);
+  
+  // Display frame rate
+  fill(255);
+  textSize(16);
+  text("Frame rate: " + int(frameRate),10,20);
+  
+}
+
+