add workaround for adreno driver issue

vtm/src/org/oscim/backend/GLAdapter.java

@@ -29,6 +29,12 @@ public class GLAdapter {
 
 	public static boolean NON_PREMUL_CANVAS;
 
+	/**
+	 * Set false as workaround for adreno driver issue:
+	 * https://github.com/opensciencemap/vtm/issues/52
+	 */
+	public static boolean VBO_TEXTURE_LAYERS = false;
+
 	public static GL20 get() {
 		if (g == null)
 			throw new IllegalStateException();

vtm/src/org/oscim/layers/marker/MarkerRenderer.java

@@ -19,6 +19,7 @@ package org.oscim.layers.marker;
 
 import java.util.Comparator;
 
+import org.oscim.backend.GLAdapter;
 import org.oscim.core.MercatorProjection;
 import org.oscim.core.Point;
 import org.oscim.core.Tile;
@@ -61,6 +62,8 @@ public class MarkerRenderer extends ElementRenderer {
 	}
 
 	public MarkerRenderer(MarkerLayer<MarkerItem> markerLayer, MarkerSymbol defaultSymbol) {
+		layers.useVBO = GLAdapter.VBO_TEXTURE_LAYERS;
+
 		mSymbolLayer = new SymbolLayer();
 		mMarkerLayer = markerLayer;
 		mDefaultMarker = defaultSymbol;

vtm/src/org/oscim/layers/tile/vector/labeling/TextRenderer.java

@@ -30,6 +30,8 @@ package org.oscim.layers.tile.vector.labeling;
 // 5 QuadTree might be handy
 //
 
+import org.oscim.backend.GL20;
+import org.oscim.backend.GLAdapter;
 import org.oscim.layers.tile.vector.labeling.LabelLayer.Worker;
 import org.oscim.renderer.ElementRenderer;
 import org.oscim.renderer.GLState;
@@ -47,6 +49,8 @@ class TextRenderer extends ElementRenderer {
 
 	public TextRenderer(Worker worker) {
 		mWorker = worker;
+
+		layers.useVBO = GLAdapter.VBO_TEXTURE_LAYERS;
 	}
 
 	long lastDraw = 0;
@@ -77,14 +81,17 @@ class TextRenderer extends ElementRenderer {
 		GLState.test(false, false);
 		//Debug.draw(pos, layers);
 
-		layers.vbo.bind();
+		if (layers.useVBO)
+			layers.vbo.bind();
+		else
+			GL.glBindBuffer(GL20.GL_ARRAY_BUFFER, 0);
 
 		float scale = (float) (v.pos.scale / mMapPosition.scale);
 
 		setMatrix(v, false);
 
 		for (RenderElement l = layers.getTextureLayers(); l != null;)
-			l = TextureLayer.Renderer.draw(l, v, scale);
+			l = TextureLayer.Renderer.draw(layers, l, v, scale);
 	}
 
 }

vtm/src/org/oscim/renderer/ElementRenderer.java

@@ -23,6 +23,8 @@ import static org.oscim.renderer.elements.RenderElement.POLYGON;
 import static org.oscim.renderer.elements.RenderElement.SYMBOL;
 import static org.oscim.renderer.elements.RenderElement.TEXLINE;
 
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
 import java.nio.ShortBuffer;
 
 import org.oscim.backend.GL20;
@@ -80,7 +82,11 @@ public abstract class ElementRenderer extends LayerRenderer {
 	protected synchronized void render(GLViewport v) {
 		MapPosition layerPos = mMapPosition;
 
-		layers.vbo.bind();
+		if (layers.useVBO)
+			layers.vbo.bind();
+		else
+			GL.glBindBuffer(GL20.GL_ARRAY_BUFFER, 0);
+
 		GLState.test(false, false);
 		GLState.blend(true);
 
@@ -121,7 +127,7 @@ public abstract class ElementRenderer extends LayerRenderer {
 				continue;
 			}
 			if (l.type == SYMBOL) {
-				l = TextureLayer.Renderer.draw(l, v, div);
+				l = TextureLayer.Renderer.draw(layers, l, v, div);
 				continue;
 			}
 			log.debug("invalid layer {}", l.type);
@@ -144,7 +150,7 @@ public abstract class ElementRenderer extends LayerRenderer {
 			return;
 		}
 
-		if (layers.vbo == null)
+		if (layers.useVBO && layers.vbo == null)
 			layers.vbo = BufferObject.get(GL20.GL_ARRAY_BUFFER, newSize);
 
 		if (uploadLayers(layers, newSize, true))
@@ -157,7 +163,15 @@ public abstract class ElementRenderer extends LayerRenderer {
 		if (addFill)
 			newSize += 8;
 
-		ShortBuffer sbuf = MapRenderer.getShortBuffer(newSize);
+		ShortBuffer sbuf;
+		if (layers.useVBO) {
+			sbuf = MapRenderer.getShortBuffer(newSize);
+		} else {
+			layers.vertexArrayBuffer = ByteBuffer
+			    .allocateDirect(newSize * 2)
+			    .order(ByteOrder.nativeOrder());
+			sbuf = layers.vertexArrayBuffer.asShortBuffer();
+		}
 
 		if (addFill)
 			sbuf.put(fillCoords, 0, 8);
@@ -172,8 +186,9 @@ public abstract class ElementRenderer extends LayerRenderer {
 			        + " buffer fill: " + sbuf.remaining());
 			return false;
 		}
+		if (layers.useVBO)
+			layers.vbo.loadBufferData(sbuf.flip(), newSize * 2);
 
-		layers.vbo.loadBufferData(sbuf.flip(), newSize * 2);
 		return true;
 	}
 

vtm/src/org/oscim/renderer/elements/ElementLayers.java

@@ -21,6 +21,7 @@ import static org.oscim.renderer.elements.RenderElement.MESH;
 import static org.oscim.renderer.elements.RenderElement.POLYGON;
 import static org.oscim.renderer.elements.RenderElement.TEXLINE;
 
+import java.nio.ByteBuffer;
 import java.nio.ShortBuffer;
 
 import org.oscim.backend.GL20;
@@ -72,6 +73,10 @@ public class ElementLayers extends TileData {
 	 * ...
 	 */
 	public BufferObject vbo;
+	public boolean useVBO = true;
+
+	/* holds vertex data for rendering when not using VBO */
+	public ByteBuffer vertexArrayBuffer;
 
 	/**
 	 * To not need to switch VertexAttribPointer positions all the time:
@@ -379,6 +384,8 @@ public class ElementLayers extends TileData {
 
 		if (vbo != null)
 			vbo = BufferObject.release(vbo);
+
+		vertexArrayBuffer = null;
 	}
 
 	@Override

vtm/src/org/oscim/renderer/elements/TextureLayer.java

@@ -150,14 +150,15 @@ public abstract class TextureLayer extends RenderElement {
 			pool.init(0);
 		}
 
-		public static RenderElement draw(RenderElement l, GLViewport v, float scale) {
+		public static RenderElement draw(ElementLayers layers, RenderElement l,
-			shader.useProgram();
+		        GLViewport v, float scale) {
 
 			GLState.test(false, false);
 			GLState.blend(true);
 
-			TextureLayer tl = (TextureLayer) l;
+			shader.useProgram();
 
+			TextureLayer tl = (TextureLayer) l;
 			GL.glUniform1f(shader.uScale, tl.fixed ? 1 / scale : 1);
 
 			v.proj.setAsUniform(shader.uProj);
@@ -179,18 +180,31 @@ public abstract class TextureLayer extends RenderElement {
 					 * / 6(indices) == 8) */
 					int off = (t.offset + i) * 8 + tl.offset;
 
-					GL.glVertexAttribPointer(shader.aPos, 4,
+					if (layers.useVBO) {
-					                         GL20.GL_SHORT, false, 12, off);
+						GL.glVertexAttribPointer(shader.aPos, 4,
-
+						                         GL20.GL_SHORT,
-					GL.glVertexAttribPointer(shader.aTexCoord, 2,
+						                         false, 12, off);
-					                         GL20.GL_SHORT, false, 12, off + 8);
 
+						GL.glVertexAttribPointer(shader.aTexCoord, 2,
+						                         GL20.GL_SHORT,
+						                         false, 12, off + 8);
+					} else {
+						layers.vertexArrayBuffer.position(off);
+						GL.glVertexAttribPointer(shader.aPos, 4,
+						                         GL20.GL_SHORT, false, 12,
+						                         layers.vertexArrayBuffer);
+						layers.vertexArrayBuffer.position(off + 8);
+						GL.glVertexAttribPointer(shader.aTexCoord,
+						                         2, GL20.GL_SHORT, false, 12,
+						                         layers.vertexArrayBuffer);
+					}
 					int numVertices = t.vertices - i;
 					if (numVertices > maxVertices)
 						numVertices = maxVertices;
 
 					GL.glDrawElements(GL20.GL_TRIANGLES, numVertices,
 					                  GL20.GL_UNSIGNED_SHORT, 0);
+
 				}
 			}