Solve chinese postman in WorldObject class

src/audio/AudioClient.java

@@ -42,6 +42,9 @@ public class AudioClient {
     AudioPlayer player = new AudioPlayer(SAMPLE_RATE, frames, ROTATE_SPEED, TRANSLATION_SPEED,
         TRANSLATION, SCALE, WEIGHT);
     System.out.println("Starting audio stream");
-    player.play();
+    new Thread(player).start();
+    while (true) {
+
+    }
   }
 }

src/audio/AudioPlayer.java

@@ -14,7 +14,7 @@ import shapes.Vector2;
 
 import java.util.List;
 
-public class AudioPlayer {
+public class AudioPlayer implements Runnable {
 
   private final XtFormat FORMAT;
 
@@ -141,7 +141,12 @@ public class AudioPlayer {
     return frames.get(currentFrame).get(currentShape);
   }
 
-  public void play() {
+  public void addFrame(List<Shape> frame) {
+    frames.add(frame);
+  }
+
+  @Override
+  public void run() {
     try (XtAudio audio = new XtAudio(null, null, null, null)) {
       XtService service = XtAudio.getServiceBySetup(XtSetup.CONSUMER_AUDIO);
       try (XtDevice device = service.openDefaultDevice(true)) {

src/engine/Camera.java

@@ -1,5 +1,7 @@
 package engine;
 
+import java.util.HashMap;
+import java.util.Map;
 import shapes.Line;
 import shapes.Vector2;
 
@@ -40,17 +42,17 @@ public class Camera {
   }
 
   public List<Line> draw(WorldObject worldObject) {
-    return getFrame(getProjectedVertices(worldObject), worldObject.getEdgeData());
+    return getFrame(getProjectedVertices(worldObject), worldObject.getVertexPath());
   }
 
-  public List<Vector2> getProjectedVertices(WorldObject worldObject) {
-    List<Vector2> vertices = new ArrayList<>();
+  public Map<Vector3, Vector2> getProjectedVertices(WorldObject worldObject) {
+    Map<Vector3, Vector2> projectionMap = new HashMap<>();
 
     for (Vector3 vertex : worldObject.getVertices()) {
-      vertices.add(project(vertex));
+      projectionMap.put(vertex, project(vertex));
     }
 
-    return vertices;
+    return projectionMap;
   }
 
   // Automatically finds the correct Z position to use to view the world object properly.
@@ -73,7 +75,7 @@ public class Camera {
     List<Vector2> vertices = new ArrayList<>();
 
     for (int i = 0; i < SAMPLE_RENDER_SAMPLES - 1; i++) {
-      vertices.addAll(getProjectedVertices(clone));
+      vertices.addAll(getProjectedVertices(clone).values());
       clone.rotate(rotation);
     }
 
@@ -111,18 +113,14 @@ public class Camera {
     );
   }
 
-  public List<Line> getFrame(List<Vector2> vertices, List<Integer> connections) {
+  public List<Line> getFrame(Map<Vector3, Vector2> projectionMap, List<Vector3> vertexPath) {
     List<Line> lines = new ArrayList<>();
 
-    for (int i = 0; i < connections.size(); i += 2) {
-      Vector2 start = vertices.get(Math.abs(connections.get(i)));
-      Vector2 end = vertices.get(Math.abs(connections.get(i + 1)));
-      double x1 = start.getX();
-      double y1 = start.getY();
-      double x2 = end.getX();
-      double y2 = end.getY();
-
-      lines.add(new Line(x1, y1, x2, y2));
+    for (int i = 0; i < vertexPath.size(); i += 2) {
+      lines.add(new Line(
+          projectionMap.get(vertexPath.get(i)),
+          projectionMap.get(vertexPath.get(i + 1))
+      ));
     }
 
     return lines;

src/engine/Vector3.java

@@ -1,6 +1,8 @@
 package engine;
 
 import java.util.List;
+import java.util.Objects;
+import shapes.Vector2;
 
 public final class Vector3 {
 
@@ -78,6 +80,10 @@ public final class Vector3 {
     );
   }
 
+  public double distance(Vector3 vector) {
+    return Math.sqrt(Math.pow(vector.x, 2) + Math.pow(vector.y, 2) + Math.pow(vector.z, 2));
+  }
+
   public static Vector3 meanPoint(List<Vector3> points) {
     Vector3 mean = new Vector3();
 
@@ -88,6 +94,34 @@ public final class Vector3 {
     return mean.scale(1f / (points.size()));
   }
 
+  @Override
+  public boolean equals(Object obj) {
+    if (this == obj) {
+      return true;
+    }
+    if (obj == null || getClass() != obj.getClass()) {
+      return false;
+    }
+    Vector3 point = (Vector3) obj;
+    return x == point.x && y == point.y && z== point.z;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(x, y, z);
+  }
+
+  private static double round(double value, int places) {
+    if (places < 0) {
+      throw new IllegalArgumentException();
+    }
+
+    long factor = (long) Math.pow(10, places);
+    value *= factor;
+
+    return (double) Math.round(value) / factor;
+  }
+
   public Vector3 clone() {
     return new Vector3(x, y, z);
   }

src/engine/WorldObject.java

@@ -3,36 +3,102 @@ package engine;
 import com.mokiat.data.front.parser.*;
 
 import java.io.FileInputStream;
-import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
+import java.util.Set;
+import org.jgrapht.Graph;
+import org.jgrapht.alg.connectivity.ConnectivityInspector;
+import org.jgrapht.alg.cycle.ChinesePostman;
+import org.jgrapht.graph.AsSubgraph;
+import org.jgrapht.graph.DefaultUndirectedWeightedGraph;
+import org.jgrapht.graph.DefaultWeightedEdge;
 
 public class WorldObject {
 
   private final List<Vector3> vertices;
-  private final List<Integer> edgeData;
+
+  // These should be a path of vertices from the above vertex list.
+  private List<Vector3> vertexPath;
   private Vector3 position;
   private Vector3 rotation;
 
-  public WorldObject(List<Vector3> vertices, List<Integer> edgeData, Vector3 position,
-      Vector3 rotation) {
+  private WorldObject(List<Vector3> vertices, List<Vector3> vertexPath, Vector3 position, Vector3 rotation) {
     this.vertices = vertices;
-    this.edgeData = edgeData;
     this.position = position;
     this.rotation = rotation;
+    this.vertexPath = vertexPath;
+  }
+
+  private WorldObject(List<Vector3> vertices, Vector3 position, Vector3 rotation) {
+    this(vertices, new ArrayList<>(), position, rotation);
   }
 
   public WorldObject(String filename, Vector3 position, Vector3 rotation) throws IOException {
-    this(new ArrayList<>(), new ArrayList<>(), position, rotation);
-    loadFromFile(filename);
+    this(new ArrayList<>(), position, rotation);
+    this.vertexPath = getDrawPath(loadFromFile(filename));
   }
 
   public WorldObject(String filename) throws IOException {
     this(filename, new Vector3(), new Vector3());
   }
 
+  public List<Vector3> getVertexPath() {
+    List<Vector3> newVertices = new ArrayList<>();
+
+    for (Vector3 vertex : vertexPath) {
+      newVertices.add(vertex.rotate(rotation).add(position));
+    }
+
+    return newVertices;
+  }
+
+  public List<Vector3> getDrawPath(List<Integer> edgeData) {
+    Graph<Vector3, DefaultWeightedEdge> graph = new DefaultUndirectedWeightedGraph<>(
+        DefaultWeightedEdge.class);
+
+    List<Vector3> vertexPath = new ArrayList<>();
+
+    // Add all lines in frame to graph as vertices and edges. Edge weight is determined by the
+    // length of the line as this is directly proportional to draw time.
+    for (int i = 0; i < edgeData.size(); i += 2) {
+      Vector3 start = vertices.get(edgeData.get(i));
+      Vector3 end = vertices.get(edgeData.get(i + 1));
+      graph.addVertex(start);
+      graph.addVertex(end);
+
+      DefaultWeightedEdge edge = new DefaultWeightedEdge();
+      graph.addEdge(start, end, edge);
+      graph.setEdgeWeight(edge, start.distance(end));
+    }
+
+    ConnectivityInspector<Vector3, DefaultWeightedEdge> inspector = new ConnectivityInspector<>(
+        graph);
+
+    // Chinese Postman can only be performed on connected graphs, so iterate over all connected
+    // sub-graphs.
+    for (Set<Vector3> vertices : inspector.connectedSets()) {
+      AsSubgraph<Vector3, DefaultWeightedEdge> subgraph = new AsSubgraph<>(graph, vertices);
+      ChinesePostman<Vector3, DefaultWeightedEdge> cp = new ChinesePostman<>();
+      Collection<DefaultWeightedEdge> path;
+
+      try {
+        path = cp.getCPPSolution(subgraph).getEdgeList();
+      } catch (Exception e) {
+        // Safety in case getCPPSolution fails.
+        path = subgraph.edgeSet();
+      }
+
+      for (DefaultWeightedEdge edge : path) {
+        vertexPath.add(subgraph.getEdgeSource(edge));
+        vertexPath.add(subgraph.getEdgeTarget(edge));
+      }
+    }
+
+    return vertexPath;
+  }
 
   public void rotate(Vector3 theta) {
     rotation = rotation.add(theta);
@@ -60,15 +126,13 @@ public class WorldObject {
     return newVertices;
   }
 
-  public List<Integer> getEdgeData() {
-    return edgeData;
-  }
-
-  private void loadFromFile(String filename) throws IOException {
+  private List<Integer> loadFromFile(String filename) throws IOException {
     InputStream in = new FileInputStream(filename);
     final IOBJParser parser = new OBJParser();
     final OBJModel model = parser.parse(in);
 
+    List<Integer> edgeData = new ArrayList<>();
+
     for (OBJVertex vertex : model.getVertices()) {
       vertices.add(new Vector3(vertex.x, vertex.y, vertex.z));
     }
@@ -85,10 +149,11 @@ public class WorldObject {
         }
       }
     }
+
+    return edgeData;
   }
 
   public WorldObject clone() {
-    return new WorldObject(new ArrayList<>(vertices), new ArrayList<>(edgeData), position,
-        rotation);
+    return new WorldObject(new ArrayList<>(vertices), new ArrayList<>(vertexPath), position, rotation);
   }
 }