minor updates

README.md

@@ -1,13 +1,13 @@
 # teilchen
 
-![LessonX04_StickMan](https://raw.githubusercontent.com/d3p/teilchen/master/img/LessonX04_StickMan.png)
+![LessonX04_StickMan](https://raw.githubusercontent.com/dennisppaul/teilchen/master/img/LessonX04_StickMan.png)
 
 - *teilchen* is a simple physics library based on particles, forces, constraints and behaviors. 
 - *teilchen* is also a collection of a variety of concepts useful for modeling with virtual physics and behaviors. nothing new nothing fancy, except maybe for the combination of forces ( *external forces* ) and behavior ( *internal forces* ).
 - *teilchen* is also a [processing.org](http://processing.org "Processing.org")-style library.
 - *teilchen* is a german word and a synonym for *Partikel* which translates to the english *particle*.
 
-the library is hosted on github [teilchen](https://github.com/d3p/teilchen).
+the library is hosted on github [teilchen](https://github.com/dennisppaul/teilchen).
 
 ## anatomy of a physic-based particle system
 

dist/config.build

@@ -3,4 +3,4 @@ IO_EXAMPLE_PATHS=( examples )
 PROJECT_PACKAGE=teilchen
 SKETCH_IMPORTS=( teilchen.behavior.* teilchen.constraint.* teilchen.cubicle.* teilchen.force.* teilchen.integration.* teilchen.util.* )
 BASE_COLOR=23
-ADDITIONAL_LIBS=( )
+ADDITIONAL_LIBS=(  )

dist/copy_readme.sh

@@ -4,6 +4,8 @@ LIB_NAME=$1
 ROOT=$(pwd)
 
 SRC=$ROOT/../README.md
+SRC_LICENSE=$ROOT/../LICENSE
 DST=$ROOT/../processing-library/$LIB_NAME
 
 cp "$SRC" "$DST"
+cp "$SRC_LICENSE" "$DST"

processing-library/teilchen/README.md

@@ -7,6 +7,8 @@
 - *teilchen* is also a [processing.org](http://processing.org "Processing.org")-style library.
 - *teilchen* is a german word and a synonym for *Partikel* which translates to the english *particle*.
 
+the library is hosted on github [teilchen](https://github.com/d3p/teilchen).
+
 ## anatomy of a physic-based particle system
 
 ### particles
@@ -28,3 +30,4 @@ constraints act on particle positions outside of a physical simulation. constrai
 ### integrators
 
 integrators are used to integrate acceleration and velocity to calculate the new position. the most well-known is the *euler* integrator, but there are also optimized versions like *runge-kutta* or *midpoint* or even slightly different concepts like *verlet*.
+

processing-library/teilchen/examples/Lesson03_Attractors/Lesson03_Attractors.pde

@@ -7,6 +7,9 @@ import teilchen.integration.*;
 import teilchen.util.*; 
 
 
+/*
+ * this sketch shows how to create and use attractors.
+ */
 Physics mPhysics;
 Attractor mAttractor;
 void settings() {
@@ -31,19 +34,12 @@ void setup() {
         Particle myParticle = mPhysics.makeParticle();
         myParticle.position().set(random(width), random(height));
     }
-    mPhysics.particles().get(0).fixed(true);
     /* create an attractor */
     mAttractor = new Attractor();
     mAttractor.radius(100);
     mAttractor.strength(150);
     mPhysics.add(mAttractor);
 }
-void mousePressed() {
-    /* flip the direction of the attractors strength. */
-    float myInvertedStrength = -1 * mAttractor.strength();
-    /* a negative strength turns the attractor into a repulsor */
-    mAttractor.strength(myInvertedStrength);
-}
 void draw() {
     /* set attractor to mouse position */
     mAttractor.position().set(mouseX, mouseY);
@@ -69,3 +65,9 @@ void draw() {
     ellipse(mAttractor.position().x, mAttractor.position().y,
             mAttractor.radius(), mAttractor.radius());
 }
+void mousePressed() {
+    /* flip the direction of the attractors strength. */
+    float myInvertedStrength = -1 * mAttractor.strength();
+    /* a negative strength turns the attractor into a repulsor */
+    mAttractor.strength(myInvertedStrength);
+}

processing-library/teilchen/examples/LessonX08_Schwarm/LessonX08_Schwarm.pde

@@ -20,8 +20,8 @@ void setup() {
     /* physics */
     mPhysics = new Physics();
     Teleporter mTeleporter = new Teleporter();
-    mTeleporter.min().set(0, 0, height / -2);
-    mTeleporter.max().set(width, height, height / 2);
+    mTeleporter.min().set(0, 0, height / -2.0f);
+    mTeleporter.max().set(width, height, height / 2.0f);
     mPhysics.add(mTeleporter);
     ViscousDrag myViscousDrag = new ViscousDrag();
     mPhysics.add(myViscousDrag);
@@ -59,15 +59,15 @@ class SwarmEntity extends BehaviorParticle {
     SwarmEntity() {
         maximumInnerForce(random(100.0f, 1000.0f));
         radius(10f);
-        separation = new Separation<>();
+        separation = new Separation();
         separation.proximity(20);
         separation.weight(50.0f);
         behaviors().add(separation);
-        alignment = new Alignment<>();
+        alignment = new Alignment();
         alignment.proximity(30);
         alignment.weight(30.0f);
         behaviors().add(alignment);
-        cohesion = new Cohesion<>();
+        cohesion = new Cohesion();
         cohesion.proximity(100);
         cohesion.weight(5.0f);
         behaviors().add(cohesion);
@@ -88,7 +88,7 @@ class SwarmEntity extends BehaviorParticle {
         translate(position().x, position().y, position().z);
         pushMatrix();
         PMatrix3D p = new PMatrix3D();
-        Util.pointAt(p, position(), new PVector(0, 1, 0), PVector.add(position(), velocity()));
+        teilchen.util.Util.pointAt(p, position(), new PVector(0, 1, 0), PVector.add(position(), velocity()));
         applyMatrix(p);
         noStroke();
         fill(0);

processing-library/teilchen/examples/LessonX11_NonIntersectingStructures/LessonX11_NonIntersectingStructures.pde

@@ -16,39 +16,33 @@ void setup() {
     frameRate(60);
     smooth();
     mPhysics = new Physics();
-    mPhysics.constrain_iterations_per_steps = 1;
-    /* add gravity for extra fun */
-    mPhysics.add(new Gravity());
     /* we chose verlet integration as it integrates much more nicely with sticks ( and constraints in general ) */
     Verlet myVerlet = new Verlet();
     myVerlet.damping(0.99f);
     mPhysics.setIntegratorRef(myVerlet);
+    Gravity mGravity = new Gravity(0,100,0);
+    mPhysics.add(mGravity);
     /* setup sticks to form mParticle whip */
     mParticles = new Particle[16];
-    float mSegmentLength = 20.0f;
+    float mSegmentLength = 10.0f;
     /* create sticks */
-    ArrayList<Stick> mSticks = new ArrayList();
+    final ArrayList<Stick> mSticks = new ArrayList();
     for (int i = 0; i < mParticles.length; i++) {
         mParticles[i] = mPhysics.makeParticle(i * mSegmentLength, 0, 0, 0.1f);
         if (i > 0) {
-            Stick myStick = new Stick(mParticles[i - 1], mParticles[i], mSegmentLength);
-            mSticks.add(myStick);
-            /* damp stick to release tensions from system */
-            myStick.damping(0.99f);
-            mPhysics.add(myStick);
-            if (i == 1) {
-                /* make head stick shorter */
-                myStick.restlength(10);
-            }
+            final Stick mConnection = new Stick(mParticles[i - 1], mParticles[i], mSegmentLength);
+//            mConnection.strength(3);
+//            mConnection.damping(0.99f);
+            mSticks.add(mConnection);
+            mPhysics.add(mConnection);
         }
     }
     /* create line intersection mechanism */
     for (Particle mParticle : mParticles) {
         LineIntersectionConstraint mLineIntersections = new LineIntersectionConstraint(mParticle);
         mLineIntersections.intersecting_lines().addAll(mSticks);
-        mLineIntersections.intersection_padding(1);
-        mLineIntersections.DEBUG_VIEW = g;
         mPhysics.add(mLineIntersections);
+        mLineIntersections.DEBUG_VIEW = g;
     }
     /* fix root particle so it can stick to the mouse later */
     mParticles[0].fixed(true);

processing-library/teilchen/examples/LessonX12_Pendulum/LessonX12_Pendulum.pde

@@ -0,0 +1,52 @@
+import teilchen.*; 
+import teilchen.behavior.*; 
+import teilchen.constraint.*; 
+import teilchen.cubicle.*; 
+import teilchen.force.*; 
+import teilchen.integration.*; 
+import teilchen.util.*; 
+
+
+Physics mPhysics;
+Particle mPendulumRoot;
+Particle mPendulumTip;
+Pulse mPulse;
+void settings() {
+    size(640, 480);
+}
+void setup() {
+    mPhysics = new Physics();
+    Gravity mGravity = new Gravity();
+    mPhysics.add(mGravity);
+    mPendulumRoot = mPhysics.makeParticle(0, 0, 0, 0.05f);
+    mPendulumRoot.position().set(width / 2, 100);
+    mPendulumRoot.fixed(true);
+    mPendulumTip = mPhysics.makeParticle(0, 0, 0, 0.05f);
+    float mSegmentLength = height / 2;
+    Spring mConnection = new Spring(mPendulumRoot, mPendulumTip, mSegmentLength);
+    mConnection.damping(0.0f);
+    mConnection.strength(10);
+    mPhysics.add(mConnection);
+    mPulse = new Pulse(mPendulumTip);
+    mPulse.damping(0.99f);
+    mPhysics.add(mPulse);
+}
+void draw() {
+    final int NUM_ITERATIONS = 5;
+    for (int i = 0; i < NUM_ITERATIONS; i++) {
+        mPhysics.step(1.0f / (frameRate * NUM_ITERATIONS));
+    }
+    background(255);
+    Particle p1 = mPendulumRoot;
+    Particle p2 = mPendulumTip;
+    stroke(0, 192);
+    noFill();
+    line(p1.position().x, p1.position().y, p2.position().x, p2.position().y);
+    stroke(255, 0, 0);
+    fill(255);
+    ellipse(p1.position().x, p1.position().y, 10, 10);
+    ellipse(p2.position().x, p2.position().y, 20, 20);
+}
+void mousePressed() {
+    mPulse.force().set(mPendulumTip.velocity().normalize().mult(100));
+}

processing-library/teilchen/src/teilchen/BasicParticle.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/BehaviorParticle.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/ConditionalParticle.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/IBehaviorParticle.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/IConnection.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/Particle.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/Physics.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -40,16 +40,14 @@ public class Physics {
 
     public static final float EPSILON = 0.001f;
     public static boolean HINT_UPDATE_OLD_POSITION = true;
-    private final ArrayList<Particle> mParticles;
-    private final ArrayList<IForce> mForces;
-    private final ArrayList<IConstraint> mConstraints;
     public boolean HINT_OPTIMIZE_STILL = true;
-
-    public boolean HINT_REMOVE_DEAD = true;
-
     public boolean HINT_RECOVER_NAN = true;
-
+    public boolean HINT_REMOVE_DEAD = true;
     public int constrain_iterations_per_steps = 1;
+    public int integrations_per_steps = 1;
+    private final ArrayList<Particle> mParticles;
+    private final ArrayList<IForce> mForces;
+    private final ArrayList<IConstraint> mConstraints;
     private IIntegrator mIntegrator;
 
     public Physics() {
@@ -85,19 +83,19 @@ public Particle particles(final int theIndex) {
         return mParticles.get(theIndex);
     }
 
-    public BasicParticle makeParticle() {
-        BasicParticle myParticle = new BasicParticle();
-        mParticles.add(myParticle);
-        return myParticle;
-    }
-
     public BasicParticle makeParticle(final PVector thePosition) {
         BasicParticle myParticle = makeParticle();
         myParticle.setPositionRef(thePosition);
         myParticle.old_position().set(myParticle.position());
         return myParticle;
     }
 
+    public BasicParticle makeParticle() {
+        BasicParticle myParticle = new BasicParticle();
+        mParticles.add(myParticle);
+        return myParticle;
+    }
+
     public BasicParticle makeParticle(final float x, final float y) {
         BasicParticle myParticle = makeParticle();
         myParticle.position().set(x, y);
@@ -277,7 +275,9 @@ public void step(final float theDeltaTime) {
     }
 
     protected synchronized void integrate(float theDeltaTime) {
-        mIntegrator.step(theDeltaTime, this);
+        for (int j = 0; j < integrations_per_steps; j++) {
+            mIntegrator.step(theDeltaTime / integrations_per_steps, this);
+        }
     }
 
     protected synchronized void handleForces() {

processing-library/teilchen/src/teilchen/ShortLivedParticle.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/VectorfieldParticle.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/behavior/Alignment.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/behavior/Arrival.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public

processing-library/teilchen/src/teilchen/behavior/Cohesion.java

@@ -1,7 +1,7 @@
 /*
  * Teilchen
  *
- * Copyright (C) 2015
+ * Copyright (C) 2020
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public