diff --git a/vtm-android-example/src/org/oscim/android/test/S3DBMapActivity.java b/vtm-android-example/src/org/oscim/android/test/S3DBMapActivity.java
index 2f655620..8d234ac0 100644
--- a/vtm-android-example/src/org/oscim/android/test/S3DBMapActivity.java
+++ b/vtm-android-example/src/org/oscim/android/test/S3DBMapActivity.java
@@ -1,8 +1,10 @@
 package org.oscim.android.test;
 
 import org.oscim.android.cache.TileCache;
+import org.oscim.layers.GenericLayer;
+import org.oscim.layers.tile.TileLayer;
 import org.oscim.layers.tile.s3db.S3DBLayer;
-import org.oscim.layers.tile.vector.labeling.LabelLayer;
+import org.oscim.renderer.OffscreenRenderer;
 import org.oscim.theme.VtmThemes;
 import org.oscim.tiling.TileSource;
 import org.oscim.tiling.source.oscimap4.OSciMap4TileSource;
@@ -28,8 +30,13 @@ public class S3DBMapActivity extends BaseMapActivity {
 			mS3dbCache.setCacheSize(512 * (1 << 10));
 			ts.setCache(mS3dbCache);
 		}
+		TileLayer tl = new S3DBLayer(mMap, ts);
+		OffscreenRenderer or = new OffscreenRenderer(mMap.getWidth(),
+		                                             mMap.getHeight());
+		or.setRenderer(tl.getRenderer());
+		mMap.layers().add(tl);
 
-		mMap.layers().add(new S3DBLayer(mMap, ts));
+		mMap.layers().add(new GenericLayer(mMap, or));
 		mMap.layers().add(new LabelLayer(mMap, mBaseLayer));
 	}
 
diff --git a/vtm/src/org/oscim/layers/tile/s3db/S3DBLayer.java b/vtm/src/org/oscim/layers/tile/s3db/S3DBLayer.java
index 6df7ecd5..4f7db87a 100644
--- a/vtm/src/org/oscim/layers/tile/s3db/S3DBLayer.java
+++ b/vtm/src/org/oscim/layers/tile/s3db/S3DBLayer.java
@@ -39,7 +39,7 @@ public class S3DBLayer extends TileLayer {
 		return new S3DBTileLoader(getManager(), mTileSource);
 	}
 
-	static class S3DBRenderer extends TileRenderer {
+	public static class S3DBRenderer extends TileRenderer {
 		ExtrusionRenderer mExtRenderer;
 
 		public S3DBRenderer() {
@@ -57,6 +57,10 @@ public class S3DBLayer extends TileLayer {
 		protected synchronized void render(GLViewport v) {
 			mExtRenderer.render(v);
 		}
+
+		public synchronized void render2(GLViewport v) {
+			mExtRenderer.render2(v);
+		}
 	}
 
 	static int getColor(String color, boolean roof) {
@@ -97,7 +101,7 @@ public class S3DBLayer extends TileLayer {
 			return Color.LTGRAY;
 
 		if ("transparent" == color)
-			return Color.get(64, 64, 64, 64);
+			return Color.get(128, 128, 128, 128);
 
 		Integer css = ColorsCSS.get(color);
 
diff --git a/vtm/src/org/oscim/layers/tile/s3db/S3DBTileLoader.java b/vtm/src/org/oscim/layers/tile/s3db/S3DBTileLoader.java
index 66ad95f7..92c1abc8 100644
--- a/vtm/src/org/oscim/layers/tile/s3db/S3DBTileLoader.java
+++ b/vtm/src/org/oscim/layers/tile/s3db/S3DBTileLoader.java
@@ -3,9 +3,11 @@ package org.oscim.layers.tile.s3db;
 import static org.oscim.layers.tile.s3db.S3DBLayer.getMaterialColor;
 
 import org.oscim.backend.canvas.Color;
+import org.oscim.core.GeometryBuffer;
 import org.oscim.core.GeometryBuffer.GeometryType;
 import org.oscim.core.MapElement;
 import org.oscim.core.MercatorProjection;
+import org.oscim.core.Tag;
 import org.oscim.layers.tile.MapTile;
 import org.oscim.layers.tile.TileLoader;
 import org.oscim.layers.tile.TileManager;
@@ -27,9 +29,25 @@ class S3DBTileLoader extends TileLoader {
 
 	private float mGroundScale;
 
+	static MapElement mTilePlane = new MapElement();
+
+	static {
+		mTilePlane = new MapElement();
+		GeometryBuffer g = mTilePlane;
+		g.type = GeometryType.TRIS;
+		g.points = new float[] {
+		        0, 0, 0,
+		        4096, 0, 0,
+		        0, 4096, 0,
+		        4096, 4096, 0 };
+		g.index = new short[] { 0, 1, 2, 2, 1, 3 };
+		mTilePlane.tags.add(new Tag("c", "transparent"));
+	}
+
 	public S3DBTileLoader(TileManager tileManager, TileSource tileSource) {
 		super(tileManager);
 		mTileDataSource = tileSource.getDataSource();
+
 	}
 
 	@Override
@@ -45,15 +63,18 @@ class S3DBTileLoader extends TileLoader {
 		mGroundScale = (float) MercatorProjection
 		    .groundResolution(lat, 1 << mTile.zoomLevel);
 
+		mRoofs = new ExtrusionLayer(0, mGroundScale, Color.get(247, 249, 250));
+
 		mLayers = new ExtrusionLayer(0, mGroundScale, Color.get(255, 254, 252));
 		//mRoofs = new ExtrusionLayer(0, mGroundScale, Color.get(207, 209, 210));
-		mRoofs = new ExtrusionLayer(0, mGroundScale, Color.get(247, 249, 250));
-		mLayers.next = mRoofs;
+		mRoofs.next = mLayers;
 
 		ElementLayers layers = new ElementLayers();
-		layers.setExtrusionLayers(mLayers);
+		layers.setExtrusionLayers(mRoofs);
 		tile.data = layers;
 
+		process(mTilePlane);
+
 		try {
 			/* query database, which calls process() callback */
 			mTileDataSource.query(mTile, this);
@@ -109,16 +130,18 @@ class S3DBTileLoader extends TileLoader {
 		}
 		ExtrusionLayer l = new ExtrusionLayer(0, mGroundScale, c);
 
-		l.next = mRoofs.next;
-		mRoofs.next = l;
+		l.next = mLayers.next;
+		mLayers.next = l;
 
 		l.add(element);
 	}
 
 	@Override
 	public void completed(QueryResult result) {
+
 		mLayers = null;
 		mRoofs = null;
+
 		super.completed(result);
 	}
 }
diff --git a/vtm/src/org/oscim/renderer/OffscreenRenderer.java b/vtm/src/org/oscim/renderer/OffscreenRenderer.java
new file mode 100644
index 00000000..9fedec68
--- /dev/null
+++ b/vtm/src/org/oscim/renderer/OffscreenRenderer.java
@@ -0,0 +1,401 @@
+package org.oscim.renderer;
+
+import java.nio.IntBuffer;
+
+import org.oscim.backend.GL20;
+import org.oscim.layers.tile.s3db.S3DBLayer.S3DBRenderer;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class OffscreenRenderer extends LayerRenderer {
+	final static Logger log = LoggerFactory.getLogger(OffscreenRenderer.class);
+
+	int fb;
+	//int depthRb;
+	int renderTex;
+	int renderDepth;
+
+	int texW;
+	int texH;
+
+	public OffscreenRenderer(int w, int h) {
+		texW = w;
+		texH = h;
+		//texW = nearestPowerOf2(texW);
+		//texH = nearestPowerOf2(texH);
+	}
+
+	int nearestPowerOf2(int x) {
+		--x;
+		x |= x >> 1;
+		x |= x >> 2;
+		x |= x >> 4;
+		x |= x >> 8;
+		x |= x >> 16;
+		return ++x;
+	}
+
+	boolean initialized;
+
+	protected boolean setup1(GLViewport viewport) {
+		IntBuffer buf = MapRenderer.getIntBuffer(1);
+
+		texW = (int) viewport.getWidth();
+		texH = (int) viewport.getHeight();
+		//texW = nearestPowerOf2(texW);
+		//texH = nearestPowerOf2(texH);
+
+		GL.glGenFramebuffers(1, buf);
+		fb = buf.get(0);
+
+		//		buf.clear();
+		//		GL.glGenRenderbuffers(1, buf);
+		//		depthRb = buf.get(0);
+
+		buf.clear();
+		GL.glGenTextures(1, buf);
+		renderTex = buf.get(0);
+
+		buf.clear();
+		GL.glGenTextures(1, buf);
+		renderDepth = buf.get(0);
+
+		GL.glBindFramebuffer(GL20.GL_FRAMEBUFFER, fb);
+
+		// generate color texture
+		GL.glBindTexture(GL20.GL_TEXTURE_2D, renderTex);
+		GLUtils.checkGlError("0");
+
+		GL.glTexParameteri(GL20.GL_TEXTURE_2D, GL20.GL_TEXTURE_WRAP_S, GL20.GL_CLAMP_TO_EDGE);
+		GL.glTexParameteri(GL20.GL_TEXTURE_2D, GL20.GL_TEXTURE_WRAP_T, GL20.GL_CLAMP_TO_EDGE);
+		GL.glTexParameteri(GL20.GL_TEXTURE_2D, GL20.GL_TEXTURE_MAG_FILTER, GL20.GL_LINEAR);
+		GL.glTexParameteri(GL20.GL_TEXTURE_2D, GL20.GL_TEXTURE_MIN_FILTER, GL20.GL_LINEAR);
+
+		GL.glTexImage2D(GL20.GL_TEXTURE_2D, 0, GL20.GL_RGBA,
+		                texW, texH, 0, GL20.GL_RGBA,
+		                GL20.GL_UNSIGNED_BYTE, null);
+
+		GL.glFramebufferTexture2D(GL20.GL_FRAMEBUFFER,
+		                          GL20.GL_COLOR_ATTACHMENT0,
+		                          GL20.GL_TEXTURE_2D,
+		                          renderTex, 0);
+
+		GLUtils.checkGlError("00");
+
+		GL.glBindTexture(GL20.GL_TEXTURE_2D, renderDepth);
+
+		GL.glTexParameteri(GL20.GL_TEXTURE_2D, GL20.GL_TEXTURE_WRAP_S, GL20.GL_CLAMP_TO_EDGE);
+		GL.glTexParameteri(GL20.GL_TEXTURE_2D, GL20.GL_TEXTURE_WRAP_T, GL20.GL_CLAMP_TO_EDGE);
+		GL.glTexParameteri(GL20.GL_TEXTURE_2D, GL20.GL_TEXTURE_MAG_FILTER, GL20.GL_NEAREST);
+		GL.glTexParameteri(GL20.GL_TEXTURE_2D, GL20.GL_TEXTURE_MIN_FILTER, GL20.GL_NEAREST);
+		GLUtils.checkGlError("1");
+
+		GL.glTexImage2D(GL20.GL_TEXTURE_2D, 0, GL20.GL_DEPTH_COMPONENT,
+		                texW, texH, 0, GL20.GL_DEPTH_COMPONENT,
+		                GL20.GL_UNSIGNED_SHORT, null);
+
+		GLUtils.checkGlError("11 " + texW + "  / " + texH);
+
+		GL.glFramebufferTexture2D(GL20.GL_FRAMEBUFFER,
+		                          GL20.GL_DEPTH_ATTACHMENT,
+		                          GL20.GL_TEXTURE_2D,
+		                          renderDepth, 0);
+
+		GLUtils.checkGlError("111");
+		// create render buffer and bind 16-bit depth buffer
+		//GL.glBindRenderbuffer(GL20.GL_RENDERBUFFER, depthRb);
+
+		//GL.glRenderbufferStorage(GL20.GL_RENDERBUFFER,
+		//                         GL20.GL_DEPTH_COMPONENT16,
+		//                         texW,
+		//                         texH);
+
+		GLUtils.checkGlError("2");
+
+		GLUtils.checkGlError("3");
+
+		//GL.glFramebufferTexture2D(GL20.GL_FRAMEBUFFER,
+		//                          GL20.GL_COLOR_ATTACHMENT0,
+		//                          GL20.GL_TEXTURE_2D,
+		//                          renderTex, 0);
+		//
+		//GL.glFramebufferRenderbuffer(GL20.GL_FRAMEBUFFER,
+		//                             GL20.GL_DEPTH_ATTACHMENT,
+		//                             GL20.GL_RENDERBUFFER,
+		//                             depthRb);
+
+		int status = GL.glCheckFramebufferStatus(GL20.GL_FRAMEBUFFER);
+		if (status != GL20.GL_FRAMEBUFFER_COMPLETE) {
+			log.debug("invalid framebuffer!!! " + status);
+			return false;
+		}
+
+		GL.glBindFramebuffer(GL20.GL_FRAMEBUFFER, 0);
+
+		//shader = GLUtils.createProgram(vShader, fShader);
+		shader = GLShader.createProgram(vShader, fSSAO);
+
+		hTex = GL.glGetUniformLocation(shader, "u_tex");
+		hTexColor = GL.glGetUniformLocation(shader, "u_texColor");
+		//hScreen = GL.glGetUniformLocation(shader, "u_screen");
+		hPixel = GL.glGetUniformLocation(shader, "u_pixel");
+		hPos = GL.glGetAttribLocation(shader, "a_pos");
+
+		return true;
+	}
+
+	int shader;
+	int hPos;
+	int hTex;
+	int hTexColor;
+	//int hScreen;
+	int hPixel;
+
+	public void enable(boolean on) {
+		if (on)
+			GL.glBindFramebuffer(GL20.GL_FRAMEBUFFER, fb);
+		else
+			GL.glBindFramebuffer(GL20.GL_FRAMEBUFFER, 0);
+	}
+
+	public void begin() {
+		GL.glBindFramebuffer(GL20.GL_FRAMEBUFFER, fb);
+		GL.glDepthMask(true);
+		GL.glClear(GL20.GL_DEPTH_BUFFER_BIT);
+	}
+
+	LayerRenderer mRenderer;
+
+	public void setRenderer(LayerRenderer renderer) {
+		mRenderer = renderer;
+	}
+
+	@Override
+	protected void update(GLViewport viewport) {
+		if (!initialized) {
+			setup1(viewport);
+			initialized = true;
+		}
+		mRenderer.update(viewport);
+		//log.debug(">>> ist ready " + mRenderer.isReady());
+		setReady(mRenderer.isReady());
+	}
+
+	@Override
+	protected void render(GLViewport viewport) {
+		//begin();
+		GL.glBindFramebuffer(GL20.GL_FRAMEBUFFER, fb);
+		GL.glViewport(0, 0, texW, texH);
+		GL.glDepthMask(true);
+		//GL.glViewport(0, 0, this.texW, this.texH);
+		GL.glClearColor(0, 0, 0, 0);
+		//GL.glDepthRangef(0, 1);
+		//GL.glClearDepthf(1);
+		GL.glClear(GL20.GL_DEPTH_BUFFER_BIT | GL20.GL_COLOR_BUFFER_BIT);
+		//GL.glClear(GL20.GL_DEPTH_BUFFER_BIT);
+
+		GLUtils.checkGlError("-----");
+		((S3DBRenderer) mRenderer).render2(viewport);
+		GLUtils.checkGlError("----");
+
+		GL.glViewport(0, 0, (int) viewport.getWidth(), (int) viewport.getHeight());
+
+		GL.glBindFramebuffer(GL20.GL_FRAMEBUFFER, 0);
+
+		GLUtils.checkGlError("--");
+
+		GLState.useProgram(shader);
+		GLUtils.checkGlError("-0");
+
+		// bind the framebuffer texture
+		GL.glActiveTexture(GL20.GL_TEXTURE1);
+		GLUtils.checkGlError("-1");
+
+		//GL.glBindTexture(GL20.GL_TEXTURE_2D, renderTex);
+		//GL.glBindTexture(GL20.GL_TEXTURE_2D, renderDepth);
+
+		GLState.bindTex2D(renderDepth);
+		GL.glUniform1i(hTex, 1);
+
+		GLUtils.checkGlError("-2");
+
+		GL.glActiveTexture(GL20.GL_TEXTURE0);
+		GLState.bindTex2D(renderTex);
+		GL.glUniform1i(hTexColor, 0);
+
+		MapRenderer.bindQuadVertexVBO(hPos, true);
+
+		//GL.glUniform2f(hScreen, texW, texH);
+		GL.glUniform2f(hPixel, (float) (1.0 / texW * 0.5), (float) (1.0 / texH * 0.5));
+
+		GLState.enableVertexArrays(hPos, -1);
+		GLUtils.checkGlError("-3");
+
+		GLState.test(false, false);
+		GLState.blend(true);
+		GL.glDrawArrays(GL20.GL_TRIANGLE_STRIP, 0, 4);
+		GLUtils.checkGlError("-4");
+
+		//GL.glDepthRangef(1, -1);
+		//GL.glClearDepthf(1);
+
+		//GL.glActiveTexture(GL20.GL_TEXTURE1);
+
+	}
+
+	private final static String vShader = ""
+	        + "precision highp float;"
+	        + "uniform vec2 u_pixel;"
+	        + "attribute vec4 a_pos;"
+	        + "varying vec2 tex_pos;"
+
+	        + "void main() {"
+	        + "  gl_Position = a_pos;"
+	        + "  tex_pos = (a_pos.xy + 1.0) * 0.5;"
+	        + "}";
+
+	private final static String fSSAO = ""
+	        + "precision highp float;"
+	        // Depth texture
+	        + "uniform sampler2D u_tex;"
+	        // Depth texture
+	        + "uniform sampler2D u_texColor;"
+	        // Random texture
+	        //+ "uniform sampler2D rand;"  
+	        //+ "uniform vec2 u_screen;"
+	        + "uniform vec2 u_pixel;"
+
+	        + "varying vec2 tex_pos;"
+	        //
+	        // gauss bell center	
+	        + "const float gdisplace = 0.2;"
+	        //
+	        // "vec2 camerarange = vec2(1.0, 8.0);"
+	        + "const float nearZ = 1.0;"//camerarange.x;"
+	        + "const float farZ = 4.0;" //camerarange.y;"
+	        //
+	        + "float getDepth(float posZ){"
+	        + "	 return (2.0 * nearZ) / (nearZ + farZ - posZ * (farZ - nearZ));"
+	        + "}"
+	        //
+	        + "float compareDepths(in float depth1, in float posZ, inout float far) {"
+	        + "  float depth2 = getDepth(posZ);"
+	        //   depth difference (0-100)
+	        + "	 float diff = (depth1 - depth2) * 100.0;"
+	        //   set 'far == 1.0' when 'diff' > 'gdisplace'
+	        + "	 far = step(diff, gdisplace);"
+	        //   gauss bell width 2, reduce left bell width to avoid self-shadowing
+	        + "  float garea = max((1.0 - far) * 2.0, 0.01);"
+	        + "	 return pow(2.7182, -2.0 * pow(diff - gdisplace,2.0) / pow(garea, 2.0));"
+	        + "}"
+	        //
+	        + "float addAO(float depth, float x1, float y1, float x2, float y2) {"
+	        + "    float ao = 0.0;"
+
+	        + "    float f_11;"
+	        + "    float z_11 = texture2D(u_tex, vec2(x1, y1)).x;"
+	        + "    float d_11 = compareDepths(depth, z_11, f_11);"
+
+	        + "    float f_12;"
+	        + "    float z_12 = texture2D(u_tex, vec2(x1, y2)).x;"
+	        + "    float d_12 = compareDepths(depth, z_12, f_12);"
+
+	        + "    float f_21;"
+	        + "    float z_21 = texture2D(u_tex, vec2(x2, y1)).x;"
+	        + "    float d_21 = compareDepths(depth, z_21, f_21);"
+
+	        + "    float f_22;"
+	        + "    float z_22 = texture2D(u_tex, vec2(x2, y2)).x;"
+	        + "    float d_22 = compareDepths(depth, z_22, f_22);"
+
+	        + "    ao += (1.0 - step(1.0, x1)) * (1.0 - step(1.0, y1))"
+	        + "          * (d_11 + f_11 * (1.0 - d_11) * d_22);"
+
+	        + "    ao += (1.0 - step(1.0, x1)) * step(0.0, y2)"
+	        + "          * (d_12 + f_12 * (1.0 - d_12) * d_21);"
+
+	        + "    ao += step(0.0, x2) * (1.0 - step(1.0, y1))"
+	        + "          * (d_21 + f_21 * (1.0 - d_21) * d_12);"
+
+	        + "    ao += step(0.0, x2) * step(0.0, y2)"
+	        + "          * (d_22 + f_22 * (1.0 - d_22) * d_11);"
+
+	        + "    return ao;"
+	        + "}"
+
+	        + "void main(void) {"
+	        //   randomization texture:
+	        //+ "	 vec2 fres = vec2(20.0, 20.0);"
+	        //+ "	vec3 random = texture2D(rand, gl_TexCoord[0].st * fres.xy);"
+	        //+ "	random = random * 2.0 - vec3(1.0);"
+
+	        //   initialize stuff:
+	        + "  vec4 color = texture2D(u_texColor, tex_pos);"
+
+	        //+ "  vec2 tex_pos = gl_FragCoord.xy / u_screen;"
+	        + "	 float depth = getDepth(texture2D(u_tex, tex_pos).x);"
+	        +
+	        "	 float ao = 0.0;"
+	        + "  float x = tex_pos.x;"
+	        + "  float y = tex_pos.y;"
+	        //   'lookup range in screen pixel'
+	        //+ "  float pw = 1.0 / u_screen.x * 0.5;"
+	        //+ "  float ph = 1.0 / u_screen.y * 0.5;"
+
+	        + "  float pw = u_pixel.x;"
+	        + "  float ph = u_pixel.y;"
+
+	        + "	 for (int i = 0; i < 4; i++) {"
+	        + "    float pwByDepth = pw / depth;"
+	        + "    float phByDepth = ph / depth;"
+
+	        //      calculate color bleeding and ao:
+
+	        + "    ao += addAO(depth, x + pwByDepth, y + phByDepth,x - pwByDepth, y - phByDepth);"
+
+	        + "    pwByDepth *= 1.2;"
+	        + "    phByDepth *= 1.2;"
+
+	        + "    ao += addAO(depth, x + pwByDepth, y, x, y - phByDepth);"
+
+	        //      sample jittering:
+	        //+ "		pw += random.x * 0.0007;"
+	        //+ "		ph += random.y * 0.0007;"
+	        //      increase sampling area:
+	        //+ "		pw *= 1.7;"
+	        //+ "		ph *= 1.7;"
+	        + "		pw *= 1.7;"
+	        + "		ph *= 1.7;"
+
+	        + "	 }"
+	        //	        //   final values, some adjusting
+	        //+ "if ((ao / 32.0) > 1.0){"
+	        //+ "	gl_FragColor = vec4(1.0,1.0,ao / 32.0 - 1.0,1.0);"
+	        //+ ""
+	        //+ "} else {"
+	        + "	 vec3 finalAO = vec3(0.25 * pow((ao / 32.0),1.2));"
+	        + "	 gl_FragColor = vec4(1.0 - finalAO, 1.0);"
+	        //+ "	 gl_FragColor = color - vec4(finalAO, 0.0);"
+	        //+ " }"
+	        //+ "	 gl_FragColor = vec4(finalAO, 1.0) * texture2D(u_texColor, tex_pos.xy);"
+	        //+ "	gl_FragColor = vec4(gl_TexCoord[0].xy,0.0,1.0);"
+	        //+ "	gl_FragColor = vec4(tex_pos.xy,0.0,1.0);"
+	        //+ "	 gl_FragColor = vec4(gl_FragCoord.xy / u_screen, 0.0, 1.0);"
+
+	        + "}";
+
+	//	private final static String fShader = ""
+	//	        + "precision mediump float;"
+	//	        + "uniform sampler2D u_tex;"
+	//	        + "uniform sampler2D u_texColor;"  // Depth texture 
+	//	        + "uniform vec2 u_screen;"
+	//	        + "varying vec2 tex_pos;"
+	//	        + "void main() {"
+	//	        //+ "  vec2 tex_pos = gl_FragCoord.xy / u_screen;"
+	//	        + " vec4 c = texture2D(u_tex, tex_pos.xy);"
+	//	        + "   gl_FragColor = c * texture2D(u_texColor, tex_pos.xy);"
+	//	        + "}";
+
+	//+ "#version 120\n"
+
+}