minor modification of the animation

src/main/java/de/neemann/digital/draw/graphics/VectorFloat.java

@@ -131,6 +131,12 @@ public class VectorFloat implements VectorInterface {
         return Objects.hash(x, y);
     }
 
+    @Override
+    public String toString() {
+        return "(x=" + x
+                + ", y=" + y
+                + ')';
+    }
 
     @Override
     public Vector round() {

src/main/java/de/neemann/digital/fsm/FSMDemos.java

@@ -13,6 +13,20 @@ public final class FSMDemos {
     private FSMDemos() {
     }
 
+
+    /**
+     * Blink
+     *
+     * @return the fsm
+     */
+    public static FSM blink() {
+        State off = new State("off");
+        State on = new State("on");
+        return new FSM(off, on)
+                .transition(on, off, null)
+                .transition(off, on, null);
+    }
+
     /**
      * Creates a debounced rotary switch decoder
      *

src/main/java/de/neemann/digital/fsm/Movable.java

@@ -13,6 +13,11 @@ import de.neemann.digital.draw.graphics.VectorFloat;
  * @param <A> the type of the implementing class
  */
 public class Movable<A extends Movable> {
+    private static final float MASS = 50f;
+    private static final float FRICTION = 0.8f;
+    private static final float MAX_FORCE = 100000f;
+    private static final float MAX_FORCE_CHECK = (float) (MAX_FORCE / Math.sqrt(2));
+
     private String values = "";
     private VectorFloat position;
     private transient VectorFloat speed;
@@ -25,7 +30,7 @@ public class Movable<A extends Movable> {
     public Movable() {
         force = new VectorFloat(0, 0);
         speed = new VectorFloat(0, 0);
-        position = new VectorFloat((float) Math.random() - 0.5f, (float) Math.random() - 0.5f).mul(100);
+        position = new VectorFloat(0, 0);
     }
 
     /**
@@ -129,15 +134,20 @@ public class Movable<A extends Movable> {
     /**
      * Moves the element
      *
-     * @param dt the time step
+     * @param dt the time step in ms
      */
     public void move(int dt) {
+        if (Math.abs(force.getXFloat()) > MAX_FORCE_CHECK || Math.abs(force.getYFloat()) > MAX_FORCE_CHECK) {
+            double len = force.len();
+            if (len > MAX_FORCE)
+                force = force.norm().mul(MAX_FORCE);
+        }
         if (speed == null)
-            speed = force.mul(dt / 200f);
+            speed = force.mul(dt / MASS);
         else
-            speed = speed.add(force.mul(dt / 200f));
+            speed = speed.add(force.mul(dt / MASS));
         setPos(position.add(speed.mul(dt / 1000f)));
-        speed = speed.mul(0.7f);
+        speed = speed.mul(FRICTION);
     }
 
     void setFSM(FSM fsm) {

src/main/java/de/neemann/digital/fsm/Transition.java

@@ -93,11 +93,14 @@ public class Transition extends Movable<Transition> {
     public void setPos(VectorFloat position) {
         if (fromState != toState) {
             VectorFloat dist = fromState.getPos().sub(toState.getPos());
+            if (dist.getXFloat() != 0 || dist.getYFloat() != 0) {
                 VectorFloat p = position.sub(fromState.getPos());
                 VectorFloat n = dist.getOrthogonal().norm();
                 float l = p.mul(n);
                 super.setPos(fromState.getPos().sub(dist.mul(0.5f)).add(n.mul(l)));
-        } else
+                return;
+            }
+        }
         super.setPos(position);
     }
 
@@ -152,7 +155,7 @@ public class Transition extends Movable<Transition> {
      */
     void initPos() {
         setPos(fromState.getPos().add(toState.getPos()).mul(0.5f)
-                .add(new VectorFloat((float) Math.random() - 0.5f, (float) Math.random() - 0.5f).mul(30)));
+                .add(new VectorFloat((float) Math.random() - 0.5f, (float) Math.random() - 0.5f).mul(2)));
     }
 
     /**