add isSpinner, isCircle etc in GameObject

src/itdelatrisu/opsu/objects/Circle.java

@@ -36,7 +36,7 @@ import org.newdawn.slick.Graphics;
 /**
  * Data type representing a circle object.
  */
-public class Circle implements GameObject {
+public class Circle extends GameObject {
 	/** The diameter of hit circles. */
 	private static float diameter;
 
@@ -208,4 +208,20 @@ public class Circle implements GameObject {
 
 	@Override
 	public void reset() {}
+
+	@Override
+	public boolean isCircle() {
+		return true;
+	}
+
+	@Override
+	public boolean isSlider() {
+		return false;
+	}
+
+	@Override
+	public boolean isSpinner() {
+		return false;
+	}
+
 }

src/itdelatrisu/opsu/objects/GameObject.java

@@ -92,4 +92,9 @@ public abstract class GameObject {
 	 * Resets all internal state so that the hit object can be reused.
 	 */
 	public abstract void reset();
+
+	public abstract boolean isCircle();
+	public abstract boolean isSlider();
+	public abstract boolean isSpinner();
+
 }

src/itdelatrisu/opsu/objects/Slider.java

@@ -40,7 +40,7 @@ import org.newdawn.slick.Image;
 /**
  * Data type representing a slider object.
  */
-public class Slider implements GameObject {
+public class Slider extends GameObject {
 	/** Slider ball frames. */
 	private static Image[] sliderBallImages;
 
@@ -582,4 +582,20 @@ public class Slider implements GameObject {
 		ticksHit = 0;
 		tickIntervals = 1;
 	}
+
+	@Override
+	public boolean isCircle() {
+		return false;
+	}
+
+	@Override
+	public boolean isSlider() {
+		return true;
+	}
+
+	@Override
+	public boolean isSpinner() {
+		return false;
+	}
+
 }

src/itdelatrisu/opsu/objects/Spinner.java

@@ -39,7 +39,7 @@ import org.newdawn.slick.Image;
 /**
  * Data type representing a spinner object.
  */
-public class Spinner implements GameObject {
+public class Spinner extends GameObject {
 	/** Container dimensions. */
 	private static int width, height;
 
@@ -409,4 +409,20 @@ public class Spinner implements GameObject {
 		deltaOverflow = 0;
 		isSpinning = false;
 	}
+
+	@Override
+	public boolean isCircle() {
+		return false;
+	}
+
+	@Override
+	public boolean isSlider() {
+		return false;
+	}
+
+	@Override
+	public boolean isSpinner() {
+		return true;
+	}
+
 }