add FadeStep for fading BitmapTileLayer depending on map scale

add setAlpha method to TileRenderLayer to fade bitmap tiles

vtm/src/org/oscim/layers/tile/TileManager.java

@@ -340,12 +340,15 @@ public class TileManager {
 		return true;
 	}
 
-	// /**
+	/**
-	// * @param tiles ...
+	 * @param tiles ...
-	// */
+	 */
-	// public void releaseTiles(TileSet tiles) {
+	public void releaseTiles(TileSet tileSet) {
-	//
+		// unlock previously active tiles
-	// }
+		for (int i = 0, n = tileSet.cnt; i < n; i++)
+			tileSet.tiles[i].unlock();
+		tileSet.cnt = 0;
+	}
 
 	/* package */MapTile addTile(int x, int y, int zoomLevel) {
 		MapTile tile;

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

@@ -39,16 +39,24 @@ public class TileRenderLayer extends RenderLayer {
 		mUploadSerial = 0;
 	}
 
-	boolean mFaded;
+	private int mOverdraw = 0;
+	private float mAlpha = 1;
 
-	public void setFaded(boolean faded) {
+	public void setOverdrawColor(int color) {
-		mFaded = faded;
+		mOverdraw = color;
+	}
+
+	public void setBitmapAlpha(float alpha) {
+		mAlpha = alpha;
 	}
 
 	@Override
 	public void update(MapPosition pos, boolean positionChanged, Matrices m) {
 
-		//mMapPosition.copy(pos);
+		if (mAlpha == 0){
+			mTileManager.releaseTiles(mDrawTiles);
+			return;
+		}
 
 		boolean tilesChanged;
 		synchronized (tilelock) {
@@ -74,7 +82,7 @@ public class TileRenderLayer extends RenderLayer {
 			BufferObject.checkBufferUsage(false);
 		}
 
-		TileRenderer.draw(tiles, tileCnt, pos, m, mFaded);
+		TileRenderer.draw(tiles, tileCnt, pos, m, mAlpha, mOverdraw);
 	}
 
 	@Override
@@ -327,5 +335,4 @@ public class TileRenderLayer extends RenderLayer {
 			}
 		}
 	};
-
 }

vtm/src/org/oscim/layers/tile/TileRenderer.java

@@ -35,7 +35,6 @@ import org.oscim.utils.quadtree.QuadTree;
  * This class is for rendering the Line- and PolygonLayers of visible MapTiles.
  * For visible tiles that do not have data available yet its parent in children
  * tiles are rendered when available.
- *
  */
 public class TileRenderer {
 	//private final static String TAG = TileRenderer.class.getName();
@@ -50,14 +49,28 @@ public class TileRenderer {
 	private static int mDrawSerial = 0;
 
 	private static Matrices mMatrices;
-	private static boolean mFaded;
+
+	private static float mFade;
+	private static int mOverdraw;
 
 	private static final Matrix4 mProjMatrix = new Matrix4();
 
-	static void draw(MapTile[] tiles, int tileCnt, MapPosition pos, Matrices m, boolean fade) {
+	/**
+	 * Draw tiles:
+	 *
+	 * @param fade
+	 *            alpha value for bitmap tiles
+	 * @param overdrawColor
+	 *            draw color on top, e.g. to darken the layer temporarily
+	 */
+	static void draw(MapTile[] tiles, int tileCnt, MapPosition pos, Matrices m, float fade,
+			int overdrawColor) {
+
 		mOffsetCnt = -2048;
 		mMatrices = m;
-		mFaded = fade;
+
+		mFade = fade;
+		mOverdraw = overdrawColor;
 
 		mProjMatrix.copy(m.proj);
 		// discard depth projection from tilt, we use depth buffer
@@ -197,7 +210,7 @@ public class TileRenderer {
 			//GLState.test(false, false);
 			switch (l.type) {
 				case Layer.BITMAP:
-					l = BitmapRenderer.draw(l, 1, m);
+					l = BitmapRenderer.draw(l, m, 1, mFade);
 					break;
 
 				default:
@@ -205,11 +218,7 @@ public class TileRenderer {
 			}
 		}
 
-		// clear clip-region and could also draw 'fade-effect'
+		PolygonRenderer.drawOver(m, mOverdraw);
-		if (mFaded)
-			PolygonRenderer.drawOver(m, true, 0x22000000);
-		else
-			PolygonRenderer.drawOver(m, false, 0);
 	}
 
 	private static int drawProxyChild(MapTile tile, MapPosition pos) {

vtm/src/org/oscim/layers/tile/bitmap/AbstractTileSource.java

@@ -53,4 +53,9 @@ public abstract class AbstractTileSource implements TileSource {
 		result = prime * result + this.port;
 		return result;
 	}
+
+	@Override
+	public FadeStep[] getFadeSteps() {
+		return null;
+	}
 }

vtm/src/org/oscim/layers/tile/bitmap/BitmapTileLayer.java

@@ -20,27 +20,63 @@ import java.net.URL;
 import java.net.URLConnection;
 import java.util.zip.GZIPInputStream;
 
-import org.oscim.view.MapView;
 import org.oscim.backend.CanvasAdapter;
 import org.oscim.backend.canvas.Bitmap;
+import org.oscim.core.MapPosition;
 import org.oscim.core.Tile;
 import org.oscim.layers.tile.MapTile;
 import org.oscim.layers.tile.TileLayer;
 import org.oscim.layers.tile.TileLoader;
 import org.oscim.layers.tile.TileManager;
+import org.oscim.layers.tile.bitmap.TileSource.FadeStep;
 import org.oscim.renderer.sublayers.BitmapLayer;
 import org.oscim.renderer.sublayers.Layers;
+import org.oscim.utils.FastMath;
+import org.oscim.view.MapView;
 
 
 public class BitmapTileLayer extends TileLayer<TileLoader> {
 	private static final int TIMEOUT_CONNECT = 5000;
 	private static final int TIMEOUT_READ = 10000;
+	protected static final String TAG = BitmapTileLayer.class.getName();
 
 	final TileSource mTileSource;
+	private final FadeStep[] mFade;
 
 	public BitmapTileLayer(MapView mapView, TileSource tileSource) {
 		super(mapView, tileSource.getZoomLevelMin(), tileSource.getZoomLevelMax(), 100);
 		mTileSource = tileSource;
+		mFade = mTileSource.getFadeSteps();
+
+	}
+
+	@Override
+	public void onUpdate(MapPosition pos, boolean changed, boolean clear) {
+		super.onUpdate(pos, changed, clear);
+
+		if (mFade == null) {
+			mRenderLayer.setBitmapAlpha(1);
+			return;
+		}
+
+		float alpha = 0;
+		for (FadeStep f : mFade) {
+			if (pos.scale < f.scaleStart || pos.scale > f.scaleEnd)
+				continue;
+
+			if (f.alphaStart == f.alphaEnd) {
+				alpha = f.alphaStart;
+				break;
+			}
+			double range = f.scaleEnd / f.scaleStart;
+			float a = (float)((range - (pos.scale / f.scaleStart)) / range);
+			a = FastMath.clamp(a, 0, 1);
+			// interpolate alpha between start and end
+			alpha = a * f.alphaStart + (1 - a) * f.alphaEnd;
+			break;
+		}
+
+		mRenderLayer.setBitmapAlpha(alpha);
 	}
 
 	@Override
@@ -61,7 +97,6 @@ public class BitmapTileLayer extends TileLayer<TileLoader> {
 					l.setBitmap(bitmap, Tile.SIZE, Tile.SIZE);
 
 					tile.layers.textureLayers = l;
-
 				} catch (Exception e) {
 					e.printStackTrace();
 					return false;

vtm/src/org/oscim/layers/tile/bitmap/NaturalEarth.java

@@ -20,10 +20,11 @@ import java.net.URL;
 import org.oscim.core.Tile;
 
 public class NaturalEarth extends AbstractTileSource {
-	public static final NaturalEarth INSTANCE = new NaturalEarth("city.informatik.uni-bremen.de", 80);
+	public static final NaturalEarth INSTANCE = new NaturalEarth("city.informatik.uni-bremen.de",
+			80);
 	private static final int PARALLEL_REQUESTS_LIMIT = 4;
 	private static final String PROTOCOL = "http";
-	private static final int ZOOM_LEVEL_MAX = 6;
+	private static final int ZOOM_LEVEL_MAX = 8;
 	private static final int ZOOM_LEVEL_MIN = 0;
 
 	public NaturalEarth(String hostName, int port) {
@@ -38,12 +39,14 @@ public class NaturalEarth extends AbstractTileSource {
 	@Override
 	public URL getTileUrl(Tile tile) throws MalformedURLException {
 		StringBuilder stringBuilder = new StringBuilder(32);
-		stringBuilder.append("/osci/ne_image2/");
+
+		stringBuilder.append("/tiles/ne/");
+		//stringBuilder.append("/osci/ne_image2/");
 		stringBuilder.append(tile.zoomLevel);
 		stringBuilder.append('/');
 		stringBuilder.append(tile.tileX);
 		stringBuilder.append('/');
-		stringBuilder.append((1 << tile.zoomLevel) - tile.tileY - 1);
+		stringBuilder.append(tile.tileY);
 		stringBuilder.append(".png");
 
 		return new URL(PROTOCOL, this.hostName, this.port, stringBuilder.toString());
@@ -58,4 +61,14 @@ public class NaturalEarth extends AbstractTileSource {
 	public byte getZoomLevelMin() {
 		return ZOOM_LEVEL_MIN;
 	}
+
+	@Override
+	public FadeStep[] getFadeSteps() {
+		return new FadeStep[] {
+				new FadeStep(ZOOM_LEVEL_MIN, ZOOM_LEVEL_MAX - 1, 1, 0.7f),
+				// dont fade between zoom-min/max
+				// fade above zoom max + 2, interpolate 1 to 0
+				new FadeStep(ZOOM_LEVEL_MAX - 1, ZOOM_LEVEL_MAX + 1, 0.7f, 0)
+		};
+	}
 }

vtm/src/org/oscim/layers/tile/bitmap/TileSource.java

@@ -39,4 +39,18 @@ public interface TileSource {
 	 * @return the minimum zoom level which this {@code TileSource} supports.
 	 */
 	byte getZoomLevelMin();
+
+	FadeStep[] getFadeSteps();
+
+	public class FadeStep{
+		public final double scaleStart, scaleEnd;
+		public final float alphaStart, alphaEnd;
+
+		public FadeStep(int zoomStart, int zoomEnd, float alphaStart, float alphaEnd) {
+			this.scaleStart = 1 << zoomStart;
+			this.scaleEnd = 1 << zoomEnd;
+			this.alphaStart = alphaStart;
+			this.alphaEnd = alphaEnd;
+		}
+	}
 }

vtm/src/org/oscim/renderer/layers/BasicRenderLayer.java

@@ -85,7 +85,7 @@ public abstract class BasicRenderLayer extends RenderLayer {
 			for (Layer l = layers.textureLayers; l != null;) {
 				switch (l.type) {
 					case Layer.BITMAP:
-						l = BitmapRenderer.draw(l, 1, m);
+						l = BitmapRenderer.draw(l, m, 1, 1);
 						break;
 
 					default:

vtm/src/org/oscim/renderer/layers/BitmapRenderLayer.java

@@ -92,6 +92,6 @@ public class BitmapRenderLayer extends BasicRenderLayer {
 	@Override
 	public synchronized void render(MapPosition pos, Matrices m) {
 		m.useScreenCoordinates(false, 8);
-		BitmapRenderer.draw(layers.textureLayers, 1, m);
+		BitmapRenderer.draw(layers.textureLayers, m, 1, 1);
 	}
 }

vtm/src/org/oscim/renderer/sublayers/BitmapRenderer.java

@@ -39,6 +39,8 @@ public final class BitmapRenderer {
 	private static int hTextureScreenScale;
 	private static int hTextureTexCoord;
 
+	private static int hAlpha;
+
 	public final static int INDICES_PER_SPRITE = 6;
 	final static int VERTICES_PER_SPRITE = 4;
 	final static int SHORTS_PER_VERTICE = 6;
@@ -53,9 +55,10 @@ public final class BitmapRenderer {
 		hTextureScreenScale = GL.glGetUniformLocation(mTextureProgram, "u_swidth");
 		hTextureVertex = GL.glGetAttribLocation(mTextureProgram, "vertex");
 		hTextureTexCoord = GL.glGetAttribLocation(mTextureProgram, "tex_coord");
+		hAlpha = GL.glGetUniformLocation(mTextureProgram, "u_alpha");
 	}
 
-	public static Layer draw(Layer layer, float scale, Matrices m) {
+	public static Layer draw(Layer layer, Matrices m, float scale, float alpha) {
 		//GLState.test(false, false);
 		GLState.blend(true);
 
@@ -70,7 +73,9 @@ public final class BitmapRenderer {
 		else
 			GL.glUniform1f(hTextureScale, 1);
 
+
 		GL.glUniform1f(hTextureScreenScale, 1f / GLRenderer.screenWidth);
+		GL.glUniform1f(hAlpha, alpha);
 
 		m.proj.setAsUniform(hTextureProjMatrix);
 
@@ -109,9 +114,6 @@ public final class BitmapRenderer {
 		return layer.next;
 	}
 
-	//private final static double TEX_COORD_DIV = 1.0 / (1024 * COORD_SCALE);
-	//private final static double COORD_DIV = 1.0 / GLRenderer.COORD_SCALE;
-
 	private final static String textVertexShader = ""
 			+ "precision mediump float; "
 			+ "attribute vec4 vertex;"
@@ -121,18 +123,17 @@ public final class BitmapRenderer {
 			+ "uniform float u_scale;"
 			+ "uniform float u_swidth;"
 			+ "varying vec2 tex_c;"
-			//+ "const vec2 div = vec2(" + TEX_COORD_DIV + "," + TEX_COORD_DIV + ");"
-			//+ "const float coord_scale = " + COORD_DIV + ";"
 			+ "void main() {"
 			+ "  gl_Position = u_mv * vec4(vertex.xy, 0.0, 1.0);"
-			+ "  tex_c = tex_coord;" // * div;"
+			+ "  tex_c = tex_coord;"
 			+ "}";
 
 	private final static String textFragmentShader = ""
 			+ "precision mediump float;"
 			+ "uniform sampler2D tex;"
+			+ "uniform float u_alpha;"
 			+ "varying vec2 tex_c;"
 			+ "void main() {"
-			+ "   gl_FragColor = texture2D(tex, tex_c.xy);"
+			+ "   gl_FragColor = texture2D(tex, tex_c.xy) * u_alpha;"
 			+ "}";
 }

vtm/src/org/oscim/renderer/sublayers/PolygonRenderer.java

@@ -338,7 +338,7 @@ public final class PolygonRenderer {
 		}
 	}
 
-	public static void drawOver(Matrices m, boolean drawColor, int color) {
+	public static void drawOver(Matrices m, int color) {
 		setShader(polyShader, m);
 
 		/*
@@ -346,7 +346,7 @@ public final class PolygonRenderer {
 		 * a quad with func 'always' and op 'zero'
 		 */
 
-		if (drawColor) {
+		if (color != 0) {
 			GlUtils.setColor(hPolygonColor[0], color, 1);
 			GLState.blend(true);
 		} else {
@@ -364,7 +364,7 @@ public final class PolygonRenderer {
 
 		GL.glDrawArrays(GL20.GL_TRIANGLE_STRIP, 0, 4);
 
-		if (!drawColor)
+		if (color == 0)
 			GL.glColorMask(true, true, true, true);
 	}