Cleaned up code and added comments

src/audio/AudioPlayer.java

@@ -38,6 +38,7 @@ public class AudioPlayer extends Thread {
       double drawingProgress = framesDrawn / framesToDraw;
 
       for (int c = 0; c < format.outputs; c++) {
+        // Even output indexes refer to first channel, odd indexes refer to second channel.
         ((float[]) output)[f * format.outputs] = shape.nextX(drawingProgress);
         ((float[]) output)[f * format.outputs + 1] = shape.nextY(drawingProgress);
       }
@@ -98,7 +99,11 @@ public class AudioPlayer extends Thread {
   }
 
   private static Shape currentShape() {
-    return shapes.get(currentShape % shapes.size());
+    if (currentShape >= shapes.size()) {
+      currentShape -= shapes.size();
+    }
+
+    return shapes.get(currentShape);
   }
 
   public static void setRotateSpeed(double speed) {

src/graphs/Node.java

@@ -4,6 +4,7 @@ import shapes.Vector;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 public class Node {
   private Vector location;
@@ -38,15 +39,15 @@ public class Node {
   }
 
   @Override
-  public boolean equals(Object obj) {
-    if (obj == this) {
-      return true;
-    } else if (obj instanceof Node) {
-      Node point = (Node) obj;
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    Node node = (Node) o;
+    return location.equals(node.location);
+  }
 
-      return getLocation().equals(point.getLocation());
-    } else {
-      return false;
-    }
+  @Override
+  public int hashCode() {
+    return Objects.hash(location);
   }
 }

src/shapes/Shapes.java

@@ -8,9 +8,7 @@ public class Shapes {
     List<Shape> polygon = new ArrayList<>();
 
     double theta = angleJump * 2 * Math.PI / sides;
-
     Vector rotated = start.rotate(theta);
-
     polygon.add(new Line(start, rotated, weight));
 
     while (!rotated.equals(start)) {