From 29c3f420436823f08103d682fd403f29830b16ae Mon Sep 17 00:00:00 2001
From: Hannes Janetzek <hannes.janetzek@gmail.com>
Date: Mon, 8 Apr 2013 18:07:14 +0200
Subject: [PATCH] fix concurrency bug: use a copy of RenderOverlays

---
 src/org/oscim/overlay/OverlayManager.java | 23 +++++++++++++++--------
 src/org/oscim/renderer/GLRenderer.java    | 11 +++++------
 2 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/src/org/oscim/overlay/OverlayManager.java b/src/org/oscim/overlay/OverlayManager.java
index 58537da3..178f0b38 100644
--- a/src/org/oscim/overlay/OverlayManager.java
+++ b/src/org/oscim/overlay/OverlayManager.java
@@ -17,8 +17,6 @@
 package org.oscim.overlay;
 
 import java.util.AbstractList;
-import java.util.ArrayList;
-import java.util.List;
 import java.util.concurrent.CopyOnWriteArrayList;
 
 import org.oscim.core.MapPosition;
@@ -66,9 +64,9 @@ public class OverlayManager extends AbstractList<Overlay> {
 	}
 
 	private boolean mDirtyOverlays;
-	private final List<RenderOverlay> mDrawLayers = new ArrayList<RenderOverlay>();
+	private RenderOverlay[] mDrawLayers;
 
-	public List<RenderOverlay> getRenderLayers() {
+	public RenderOverlay[] getRenderLayers() {
 		if (mDirtyOverlays)
 			updateOverlays();
 
@@ -91,14 +89,23 @@ public class OverlayManager extends AbstractList<Overlay> {
 
 		mOverlays = new Overlay[mOverlayList.size()];
 
-		mDrawLayers.clear();
+		int numRenderLayers = 0;
+
 		for (int i = 0, n = mOverlayList.size(); i < n; i++) {
+			Overlay o = mOverlayList.get(i);
+			if (o.getLayer() != null)
+				numRenderLayers++;
+
+			mOverlays[n - i - 1] = o;
+		}
+
+		mDrawLayers = new RenderOverlay[numRenderLayers];
+
+		for (int i = 0, cnt = 0, n = mOverlayList.size(); i < n; i++) {
 			Overlay o = mOverlayList.get(i);
 			RenderOverlay l = o.getLayer();
 			if (l != null)
-				mDrawLayers.add(l);
-
-			mOverlays[n - i - 1] = o;
+				mDrawLayers[cnt++] = l;
 		}
 
 		mDirtyOverlays = false;
diff --git a/src/org/oscim/renderer/GLRenderer.java b/src/org/oscim/renderer/GLRenderer.java
index 5279ddbe..ca97a90b 100644
--- a/src/org/oscim/renderer/GLRenderer.java
+++ b/src/org/oscim/renderer/GLRenderer.java
@@ -24,7 +24,6 @@ import static org.oscim.generator.JobTile.STATE_READY;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
 import java.nio.ShortBuffer;
-import java.util.List;
 import java.util.concurrent.locks.ReentrantLock;
 
 import javax.microedition.khronos.egl.EGLConfig;
@@ -483,17 +482,17 @@ public class GLRenderer implements GLSurfaceView.Renderer {
 		tilesChanged |= (uploadCnt > 0);
 
 		/* update overlays */
-		List<RenderOverlay> overlays = mMapView.getOverlayManager().getRenderLayers();
+		RenderOverlay[] overlays = mMapView.getOverlayManager().getRenderLayers();
 
-		for (int i = 0, n = overlays.size(); i < n; i++)
-			overlays.get(i).update(mMapPosition, positionChanged, tilesChanged, mMatrices);
+		for (int i = 0, n = overlays.length; i < n; i++)
+			overlays[i].update(mMapPosition, positionChanged, tilesChanged, mMatrices);
 
 		/* draw base layer */
 		TileRenderer.draw(tiles, tileCnt, pos, mMatrices);
 
 		/* draw overlays */
-		for (int i = 0, n = overlays.size(); i < n; i++) {
-			RenderOverlay renderOverlay = overlays.get(i);
+		for (int i = 0, n = overlays.length; i < n; i++) {
+			RenderOverlay renderOverlay = overlays[i];
 
 			if (renderOverlay.newData) {
 				renderOverlay.compile();