- keep screen-to-map-plane projection in Matrices so that this stays consistent for a frame

- dont modify map-plane coord array that is passed to ScanBox

src/org/oscim/layers/tile/TileRenderLayer.java

@@ -26,15 +26,15 @@ import org.oscim.utils.ScanBox;
 import org.oscim.view.MapView;
 
 import android.util.Log;
+
 public class TileRenderLayer extends RenderLayer {
 	private final static String TAG = TileRenderLayer.class.getName();
 
-	private final float[] mBoxCoords;
 	private final TileManager mTileManager;
+
 	public TileRenderLayer(MapView mapView, TileManager tileManager) {
 		super(mapView);
 		mTileManager = tileManager;
-		mBoxCoords = new float[8];
 	}
 
 	boolean mFaded;
@@ -45,10 +45,10 @@ public class TileRenderLayer extends RenderLayer {
 
 	@Override
 	public void update(MapPosition pos, boolean positionChanged, Matrices m) {
-		int serial = 0;
 
 		mMapPosition.copy(pos);
 
+		int serial = 0;
 		if (mDrawTiles != null)
 			serial = mDrawTiles.getSerial();
 
@@ -60,25 +60,18 @@ public class TileRenderLayer extends RenderLayer {
 		if (mDrawTiles == null || mDrawTiles.cnt == 0)
 			return;
 
-		boolean changed = false;
+		boolean tilesChanged = false;
-		//boolean positionChanged = false;
 
-		// check if the tiles have changed...
+		// check if tiles have changed.
-		if (serial != mDrawTiles.getSerial()) {
+		if (serial != mDrawTiles.getSerial())
-			changed = true;
+			tilesChanged = true;
-			// FIXME needed?
-			//positionChanged = true;
-		}
 
 		int tileCnt = mDrawTiles.cnt;
 		MapTile[] tiles = mDrawTiles.tiles;
 
-		if (changed || positionChanged){
+		if (tilesChanged || positionChanged)
-			float[] box = mBoxCoords;
+			updateTileVisibility(m.mapPlane);
-			mMapView.getMapViewPosition().getMapViewProjection(box);
 
-			updateTileVisibility(box);
-		}
 		tileCnt += mNumTileHolder;
 
 		/* prepare tile for rendering */
@@ -95,7 +88,6 @@ public class TileRenderLayer extends RenderLayer {
 	@Override
 	public void render(MapPosition pos, Matrices m) {
 
-
 	}
 
 	/** compile tile layer data and upload to VBOs */
@@ -236,12 +228,11 @@ public class TileRenderLayer extends RenderLayer {
 		td.cnt = 0;
 	}
 
-
 	// Add additional tiles that serve as placeholer when flipping
 	// over date-line.
 	// I dont really like this but cannot think of a better solution:
-		// the other option would be to run scanbox each time for upload,
+	// The other option would be to run scanbox each time for upload,
-		// drawing, proxies and text layer. needing to add placeholder only
+	// drawing, proxies and text layer. Adding placeholder only
 	// happens rarely, unless you live on Fidschi
 
 	/* package */int mNumTileHolder;

src/org/oscim/renderer/GLRenderer.java

@@ -74,13 +74,12 @@ public class GLRenderer implements GLSurfaceView.Renderer {
 	// bytes currently loaded in VBOs
 	private static int mBufferMemoryUsage;
 
-	private static float[] mBoxCoords;
-
 	public class Matrices {
 		// do not modify any of these
 		public final Matrix4 viewproj = new Matrix4();
 		public final Matrix4 proj = new Matrix4();
 		public final Matrix4 view = new Matrix4();
+		public final float[] mapPlane = new float[8];
 
 		// for temporary use by callee
 		public final Matrix4 mvp = new Matrix4();
@@ -132,7 +131,6 @@ public class GLRenderer implements GLSurfaceView.Renderer {
 		mMapPosition = new MapPosition();
 
 		mMatrices = new Matrices();
-		mBoxCoords = new float[8];
 
 		// tile fill coords
 		short min = 0;
@@ -291,7 +289,7 @@ public class GLRenderer implements GLSurfaceView.Renderer {
 				| GLES20.GL_DEPTH_BUFFER_BIT
 				| GLES20.GL_STENCIL_BUFFER_BIT);
 
-		boolean positionChanged = false;
+		boolean changed = false;
 
 		// get current MapPosition, set mBoxCoords (mapping of screen to model
 		// coordinates)
@@ -300,10 +298,10 @@ public class GLRenderer implements GLSurfaceView.Renderer {
 		synchronized (mMapViewPosition) {
 			mMapViewPosition.updateAnimation();
 
-			positionChanged = mMapViewPosition.getMapPosition(pos);
+			changed = mMapViewPosition.getMapPosition(pos);
 
-			if (positionChanged)
+			if (changed)
-				mMapViewPosition.getMapViewProjection(mBoxCoords);
+				mMapViewPosition.getMapViewProjection(mMatrices.mapPlane);
 
 			mMapViewPosition.getMatrix(mMatrices.view, null, mMatrices.viewproj);
 
@@ -317,7 +315,7 @@ public class GLRenderer implements GLSurfaceView.Renderer {
 		RenderLayer[] overlays = mMapView.getLayerManager().getRenderLayers();
 
 		for (int i = 0, n = overlays.length; i < n; i++)
-			overlays[i].update(mMapPosition, positionChanged, mMatrices);
+			overlays[i].update(pos, changed, mMatrices);
 
 		/* draw layers */
 		for (int i = 0, n = overlays.length; i < n; i++) {

src/org/oscim/utils/ScanBox.java

@@ -33,7 +33,9 @@ import org.oscim.core.Tile;
  * */
 public abstract class ScanBox {
 
-	public static void transScale(double x, double y, double scale, int zoom, float[] box){
+	private final float[] mBox = new float[8];
+
+	private float[] transScale(double x, double y, double scale, int zoom, float[] box){
 		scale *= Tile.SIZE;
 
 		//double curScale = Tile.SIZE * scale;
@@ -43,10 +45,12 @@ public abstract class ScanBox {
 		y *= scale;
 
 		for (int i = 0; i < 8; i += 2) {
-			box[i + 0] = (float) ((x + box[i + 0]) / div);
+			mBox[i + 0] = (float) ((x + box[i + 0]) / div);
-			box[i + 1] = (float) ((y + box[i + 1]) / div);
+			mBox[i + 1] = (float) ((y + box[i + 1]) / div);
 		}
+		return mBox;
 	}
+
 	/*
 	 * ported from Polymaps: Layer.js
 	 */
@@ -74,6 +78,7 @@ public abstract class ScanBox {
 	private Edge ab = new Edge();
 	private Edge bc = new Edge();
 	private Edge ca = new Edge();
+
 	private int minX, maxX;
 
 	protected int mZoom;
@@ -82,7 +87,8 @@ public abstract class ScanBox {
 
 	public void scan(double x, double y, double scale, int zoom, float[] box) {
 		mZoom = zoom;
-		transScale(x, y, scale, zoom, box);
+		// this does not modify 'box' parameter
+		box = transScale(x, y, scale, zoom, box);
 
 		// clip result to min/max as steep angles
 		// cause overshooting in x direction.