diff --git a/vtm/src/org/oscim/layers/tile/buildings/BuildingLayer.java b/vtm/src/org/oscim/layers/tile/buildings/BuildingLayer.java
index 053e58ada..2762037d1 100644
--- a/vtm/src/org/oscim/layers/tile/buildings/BuildingLayer.java
+++ b/vtm/src/org/oscim/layers/tile/buildings/BuildingLayer.java
@@ -47,6 +47,11 @@ public class BuildingLayer extends Layer implements TileLoaderThemeHook, ZoomLim
     public final static int MIN_ZOOM = 17;
 
     public static boolean POST_AA = false;
+
+    /**
+     * Don't draw extrusions which are covered by others.
+     * Especially if the side of extrusion is translucent.
+     */
     public static boolean TRANSLUCENT = true;
 
     private static final Object BUILDING_DATA = BuildingLayer.class.getName();
@@ -83,8 +88,9 @@ public BuildingLayer(Map map, VectorTileLayer tileLayer, int zoomMin, int zoomMa
         // Use zoomMin as zoomLimit to render buildings only once
         mZoomLimiter = new ZoomLimiter(tileLayer.getManager(), zoomMin, zoomMax, zoomMin);
 
+        // Covered extrusions must be drawn for mesh renderer
         mRenderer = new BuildingRenderer(tileLayer.tileRenderer(), mZoomLimiter,
-                mesh, !mesh && TRANSLUCENT); // alpha must be disabled for mesh renderer
+                mesh, !mesh && TRANSLUCENT);
         if (POST_AA)
             mRenderer = new OffscreenRenderer(Mode.SSAO_FXAA, mRenderer);
     }
diff --git a/vtm/src/org/oscim/layers/tile/buildings/BuildingRenderer.java b/vtm/src/org/oscim/layers/tile/buildings/BuildingRenderer.java
index 3fcbb0284..71955f24a 100644
--- a/vtm/src/org/oscim/layers/tile/buildings/BuildingRenderer.java
+++ b/vtm/src/org/oscim/layers/tile/buildings/BuildingRenderer.java
@@ -54,8 +54,8 @@ public class BuildingRenderer extends ExtrusionRenderer {
     private boolean mShow;
 
     public BuildingRenderer(TileRenderer tileRenderer, ZoomLimiter zoomLimiter,
-                            boolean mesh, boolean alpha) {
-        super(mesh, alpha);
+                            boolean mesh, boolean translucent) {
+        super(mesh, translucent);
 
         mZoomLimiter = zoomLimiter;
         mTileRenderer = tileRenderer;
diff --git a/vtm/src/org/oscim/renderer/ExtrusionRenderer.java b/vtm/src/org/oscim/renderer/ExtrusionRenderer.java
index 5bbe12e8e..f198aebab 100644
--- a/vtm/src/org/oscim/renderer/ExtrusionRenderer.java
+++ b/vtm/src/org/oscim/renderer/ExtrusionRenderer.java
@@ -32,7 +32,9 @@
 public abstract class ExtrusionRenderer extends LayerRenderer {
     static final Logger log = LoggerFactory.getLogger(ExtrusionRenderer.class);
 
+    // Don't draw extrusions which are covered by others
     private final boolean mTranslucent;
+
     private final int mMode;
     private Shader mShader;
 
@@ -42,9 +44,9 @@ public abstract class ExtrusionRenderer extends LayerRenderer {
 
     private float mZLimit = Float.MAX_VALUE;
 
-    public ExtrusionRenderer(boolean mesh, boolean alpha) {
+    public ExtrusionRenderer(boolean mesh, boolean translucent) {
         mMode = mesh ? 1 : 0;
-        mTranslucent = alpha;
+        mTranslucent = translucent;
     }
 
     public static class Shader extends GLShader {