let the base state listen to the resolution change events

src/yugecin/opsudance/core/state/BaseOpsuState.java

@@ -17,7 +17,49 @@
  */
 package yugecin.opsudance.core.state;
 
-public abstract class BaseOpsuState implements OpsuState {
+import yugecin.opsudance.core.DisplayContainer;
+import yugecin.opsudance.core.ResolutionChangeListener;
+
+public abstract class BaseOpsuState implements OpsuState, ResolutionChangeListener {
+
+	protected final DisplayContainer displayContainer;
+
+	/**
+	 * state is dirty when resolution or skin changed but hasn't rendered yet
+	 */
+	private boolean isDirty;
+	private boolean isCurrentState;
+
+	public BaseOpsuState(DisplayContainer displayContainer) {
+		this.displayContainer = displayContainer;
+		displayContainer.addResolutionChangeListener(this);
+	}
+
+	protected void revalidate() {
+	}
+
+	@Override
+	public void onDisplayResolutionChanged(int width, int height) {
+		if (isCurrentState) {
+			revalidate();
+			return;
+		}
+		isDirty = true;
+	}
+
+	@Override
+	public void enter() {
+		isCurrentState = true;
+		if (isDirty) {
+			revalidate();
+			isDirty = false;
+		}
+	}
+
+	@Override
+	public void leave() {
+		isCurrentState = false;
+	}
 
 	@Override
 	public boolean onCloseRequest() {

src/yugecin/opsudance/core/state/transitions/EmptyTransitionState.java

@@ -17,8 +17,16 @@
  */
 package yugecin.opsudance.core.state.transitions;
 
+import com.google.inject.Inject;
+import yugecin.opsudance.core.DisplayContainer;
+
 public class EmptyTransitionState extends TransitionState {
 
+	@Inject
+	public EmptyTransitionState(DisplayContainer displayContainer) {
+		super(displayContainer);
+	}
+
 	@Override
 	public void enter() {
 		finish();

src/yugecin/opsudance/core/state/transitions/FadeTransitionState.java

@@ -23,12 +23,10 @@ import yugecin.opsudance.core.DisplayContainer;
 
 public abstract class FadeTransitionState extends TransitionState {
 
-	private final DisplayContainer container;
-
 	private final Color black;
 
-	public FadeTransitionState(DisplayContainer container) {
-		this.container = container;
+	public FadeTransitionState(DisplayContainer displayContainer) {
+		super(displayContainer);
 		black = new Color(Color.black);
 	}
 
@@ -37,7 +35,7 @@ public abstract class FadeTransitionState extends TransitionState {
 		applicableState.render(g);
 		black.a = getMaskAlphaLevel((float) transitionTime / transitionTargetTime);
 		g.setColor(black);
-		g.fillRect(0, 0, container.width, container.height);
+		g.fillRect(0, 0, displayContainer.width, displayContainer.height);
 	}
 
 	protected abstract float getMaskAlphaLevel(float fadeProgress);

src/yugecin/opsudance/core/state/transitions/TransitionState.java

@@ -18,6 +18,7 @@
 package yugecin.opsudance.core.state.transitions;
 
 import org.newdawn.slick.Graphics;
+import yugecin.opsudance.core.DisplayContainer;
 import yugecin.opsudance.core.state.BaseOpsuState;
 import yugecin.opsudance.core.state.OpsuState;
 
@@ -30,6 +31,10 @@ public abstract class TransitionState extends BaseOpsuState {
 
 	private TransitionFinishedListener listener;
 
+	public TransitionState(DisplayContainer displayContainer) {
+		super(displayContainer);
+	}
+
 	public final TransitionState set(OpsuState applicableState, int targetTime, TransitionFinishedListener listener) {
 		this.applicableState = applicableState;
 		this.transitionTargetTime = targetTime;
@@ -61,12 +66,10 @@ public abstract class TransitionState extends BaseOpsuState {
 
 	@Override
 	public void enter() {
+		super.enter();
 		transitionTime = 0;
 	}
 
-	@Override
-	public void leave() { }
-
 	protected final void finish() {
 		listener.onFinish();
 	}