It doesn't crash anymore

src/awlex/ospu/polymover/ArcMover.java

@@ -8,19 +8,19 @@ import static java.lang.Math.*;
 /**
  * Created by Awlex on 13.11.2016.
  */
-public class Arc extends PolyMover {
+public class ArcMover extends PolyMover {
 	
 	private GameObject p1, middle, p2;
 	private double xm, ym, r, alpha, beta, gamma;
 	
-	public Arc(GameObject p1, GameObject middle, GameObject p2) {
+	public ArcMover(GameObject p1, GameObject middle, GameObject p2) {
 		this.p1 = p1;
 		this.middle = middle;
 		this.p2 = p2;
 		init();
 	}
 	
-	public Arc(PolyMover mover, GameObject p) {
+	public ArcMover(PolyMover mover, GameObject p) {
 		GameObject[] items = mover.getItems();
 		p1 = items[items.length - 2];
 		middle = items[items.length - 1];
@@ -40,17 +40,12 @@ public class Arc extends PolyMover {
 	
 	@Override
 	public double[] getPointAt(int time) {
-		double percent;
 		double angle;
 		if (time < middle.getTime()) {
-			time -= p1.getEndTime();
+			angle = alpha + beta * ((double) time - p1.getEndTime()) / ((middle.getTime() - p1.getEndTime()));
-			percent = ((double) time) / ((middle.getTime() - p1.getEndTime()));
-			angle = alpha + beta * percent;
 		}
 		else {
-			time -= middle.getTime();
+			angle = beta + gamma * ((double) time - middle.getTime()) / (p2.getTime() - middle.getTime());
-			percent = ((double) time) / (p2.getTime() - middle.getTime());
-			angle = beta + gamma * percent;
 		}
 		return new double[]{
 			xm + r * cos(angle),
@@ -67,7 +62,7 @@ public class Arc extends PolyMover {
 		};
 	}
 	
-	private Matrix prepareMatrix(GameObject p1, GameObject middle, GameObject p2) {
+	private static Matrix prepareMatrix(GameObject p1, GameObject middle, GameObject p2) {
 		Matrix a = new Matrix(new double[][]{
 			{1, -p1.end.x, -p1.end.y},
 			{1, -middle.end.x, -middle.end.y},
@@ -83,6 +78,11 @@ public class Arc extends PolyMover {
 	}
 	
 	public static boolean canCricleExistBetweenItems(GameObject p1, GameObject p2, GameObject p3) {
-		return !((p1.end.x == p2.start.x && p1.end.x == p3.start.x) || (p1.end.y == p2.start.y && p1.end.y == p3.start.y));
+		try {
+			prepareMatrix(p1, p2, p3);
+		} catch (RuntimeException e) {
+			return false;
+		}
+		return true;
 	}
 }

src/awlex/ospu/polymover/LineMover.java

@@ -0,0 +1,32 @@
+package awlex.ospu.polymover;
+
+import itdelatrisu.opsu.objects.DummyObject;
+import itdelatrisu.opsu.objects.GameObject;
+import yugecin.opsudance.movers.LinearMover;
+
+/**
+ * Created by Awlex on 19.11.2016.
+ */
+public class LineMover extends PolyMover {
+	
+	GameObject[] objects;
+	
+	public LineMover(GameObject[] objects, int startIndex, int count) {
+		this.objects = new GameObject[count];
+		System.arraycopy(objects, startIndex, this.objects, 0, count);
+	}
+	
+	@Override
+	public double[] getPointAt(int time) {
+		int i = 0;
+		while (time > objects[i].getTime() && i < objects.length - 1)
+			i++;
+		
+		return new LinearMover(i == 0 ? new DummyObject() : objects[i - 1], objects[i], 1).getPointAt(time);
+	}
+	
+	@Override
+	public GameObject[] getItems() {
+		return new GameObject[0];
+	}
+}

src/awlex/ospu/polymover/factory/ArcFactory.java

@@ -1,6 +1,7 @@
 package awlex.ospu.polymover.factory;
 
-import awlex.ospu.polymover.Arc;
+import awlex.ospu.polymover.ArcMover;
+import awlex.ospu.polymover.LineMover;
 import awlex.ospu.polymover.PolyMover;
 import itdelatrisu.opsu.objects.GameObject;
 
@@ -10,15 +11,16 @@ import itdelatrisu.opsu.objects.GameObject;
 public class ArcFactory implements PolyMoverFactory {
 	
 	private static final int PREFFERED_BUFFER_SIZE = 3;
-	private PolyMover arc1, arc2;
+	private PolyMover current, previous;
+	private int lastIndex;
 	
 	public double[] getPointAt(int time) {
-		if (arc2 == null) {
+		if (previous == null) {
-			return arc1.getPointAt(time);
+			return current.getPointAt(time);
 		}
 		
-		double[] point1 = arc1.getPointAt(time);
+		double[] point1 = current.getPointAt(time);
-		double[] point2 = arc2.getPointAt(time);
+		double[] point2 = previous.getPointAt(time);
 		
 		return new double[]{
 			(point1[0] + point2[0]) * 0.5,
@@ -30,18 +32,26 @@ public class ArcFactory implements PolyMoverFactory {
 	public void init(GameObject[] objects, int startIndex) {
 		if (objects == null)
 			throw new NullPointerException("Objects musn't be null");
-		arc1 = new Arc(objects[startIndex], objects[startIndex + 1], objects[startIndex + 2]);
+		
-		arc2 = null;
+		GameObject middle = objects[startIndex + 1];
+		if (middle.isSlider() || middle.isSpinner() || !ArcMover.canCricleExistBetweenItems(objects[startIndex], middle, objects[startIndex + 2]))
+			current = new LineMover(objects, startIndex, 3);
+		else
+			current = new ArcMover(objects[startIndex], middle, objects[startIndex + 2]);
+		lastIndex = startIndex + 2;
+		previous = null;
 	}
 	
 	public void update(GameObject p) {
-		GameObject[] items = (arc2 == null ? arc1 : arc2).getItems();
+		GameObject[] items = (previous == null ? current : previous).getItems();
 		GameObject last = items[items.length - 1];
 		if (last != p) {
-			if (arc2 == null)
+			if (ArcMover.canCricleExistBetweenItems(items[items.length - 2], items[items.length - 1], p)) {
-				arc2 = arc1;
+				previous = current;
-			arc1 = new Arc(arc2, p);
+				current = new ArcMover(previous, p);
+			}
 		}
+		lastIndex++;
 	}
 	
 	@Override
@@ -56,6 +66,12 @@ public class ArcFactory implements PolyMoverFactory {
 	
 	@Override
 	public boolean isInitialized() {
-		return arc1 != null;
+		return current != null;
 	}
+	
+	@Override
+	public int getLatestIndex() {
+		return lastIndex;
+	}
+	
 }

src/awlex/ospu/polymover/factory/PolyMoverFactory.java

@@ -25,4 +25,6 @@ public interface PolyMoverFactory {
 	int getPrefferedBufferSize();
 	
 	boolean isInitialized();
+	
+	int getLatestIndex();
 }

src/yugecin/opsudance/Dancer.java

@@ -266,13 +266,12 @@ public class Dancer {
 				double[] spinnerStartPoint = spinner.getPoint();
 				c.start = new Vec2f((float) spinnerStartPoint[0], (float) spinnerStartPoint[1]);
 			}
-			GameObject g = gameObjects[objectIndex + 2];
+			
-			if (!g.isSpinner() && !g.isSlider())
+			if (polyMoverFactory.isInitialized() && polyMoverFactory.getLatestIndex() < objectIndex + polyMoverFactory.getPrefferedBufferSize() - 1) {
-				if (polyMoverFactory.isInitialized()) {
+				polyMoverFactory.update(gameObjects[polyMoverFactory.getPrefferedBufferSize() - 1]);
-					polyMoverFactory.update(g);
+			} else {
-				} else {
+				polyMoverFactory.init(gameObjects, objectIndex);
-					polyMoverFactory.init(gameObjects, objectIndex);
+			}
-				}
 		}
 		
 		if (time < c.getTime()) {