draw text textures only once per string

- unify duplicate strings from different tiles (as side-effect save some bytes)
- fix 'advance by width' in texture drawing

src/org/oscim/renderer/layer/Layers.java

@@ -22,7 +22,6 @@ import android.util.Log;
  * @author Hannes Janetzek
  */
 public class Layers {
-
 	// mixed Polygon and Line layers
 	public Layer layers;
 	public Layer textureLayers;
@@ -34,6 +33,10 @@ public class Layers {
 	// 3. other layers keep their byte offset in Layer.offset
 	public int lineOffset;
 
+	// time when layers became first rendered (in uptime)
+	// used for animations
+	public long time;
+
 	private Layer mCurLayer;
 
 	// get or add the line- or polygon-layer for a level.
@@ -198,7 +201,6 @@ public class Layers {
 		}
 
 		for (l = textureLayers; l != null; l = l.next) {
-			VertexPool.release(l.pool);
 			l.clear();
 		}
 

src/org/oscim/renderer/layer/SymbolLayer.java

@@ -207,6 +207,13 @@ public final class SymbolLayer extends TextureLayer {
 				short tx = (short) ((int) (SCALE * it2.x) & LBIT_MASK | (it2.billboard ? 1 : 0));
 				short ty = (short) (SCALE * it2.y);
 
+				if (pos == VertexPoolItem.SIZE) {
+					si.used = VertexPoolItem.SIZE;
+					si = si.next = VertexPool.get();
+					buf = si.vertices;
+					pos = 0;
+				}
+
 				// top-left
 				buf[pos++] = tx;
 				buf[pos++] = ty;
@@ -238,17 +245,9 @@ public final class SymbolLayer extends TextureLayer {
 
 				// six elements used to draw the four vertices
 				curIndices += TextureRenderer.INDICES_PER_SPRITE;
-
-				if (pos == VertexPoolItem.SIZE) {
-					si.used = VertexPoolItem.SIZE;
-					si = si.next = VertexPool.get();
-					buf = si.vertices;
-					pos = 0;
 			}
-
 			x += width;
 		}
-		}
 
 		to.offset = offsetIndices;
 		to.vertices = curIndices;
@@ -263,8 +262,10 @@ public final class SymbolLayer extends TextureLayer {
 	protected void clear() {
 		TextureObject.release(textures);
 		SymbolItem.release(symbols);
+		VertexPool.release(pool);
 		textures = null;
 		symbols = null;
+		pool = null;
 		verticesCnt = 0;
 	}
 }

src/org/oscim/renderer/layer/TextItem.java

@@ -34,6 +34,21 @@ public class TextItem {
 		}
 	}
 
+	public static void append(TextItem ti, TextItem in) {
+		if (ti == null)
+			return;
+		if (ti.next == null) {
+			in.next = ti.next;
+			ti.next = in;
+		}
+		TextItem t = ti;
+		while (t.next != null)
+			t = t.next;
+
+		in.next = t.next;
+		t.next = in;
+	}
+
 	public static void release(TextItem ti) {
 		if (ti == null)
 			return;

src/org/oscim/renderer/layer/TextLayer.java

@@ -22,7 +22,7 @@ import android.util.Log;
 
 public final class TextLayer extends TextureLayer {
 
-	// private static String TAG = TextureLayer.class.getSimpleName();
+	//private static String TAG = TextureLayer.class.getName();
 
 	private final static int TEXTURE_WIDTH = TextureObject.TEXTURE_WIDTH;
 	private final static int TEXTURE_HEIGHT = TextureObject.TEXTURE_HEIGHT;
@@ -61,10 +61,8 @@ public final class TextLayer extends TextureLayer {
 				else
 					prev.next = it.next;
 
-				verticesCnt -= 4;
 				return true;
 			}
-
 			prev = it;
 		}
 
@@ -72,21 +70,42 @@ public final class TextLayer extends TextureLayer {
 	}
 
 	public void addText(TextItem item) {
-		verticesCnt += 4;
 		TextItem it = labels;
 
 		for (; it != null; it = it.next) {
-			if (it.text == item.text) {
+			// todo add captions at the end
-				// insert after text of same type
+			//if (item.text.caption && !it.text.caption)
+			//continue;
+			//if (!item.text.caption && it.text.caption)
+			//continue;
+
+			if (item.text == it.text) {
+				while (it.next != null
+						// break if next item uses different text style
+						&& item.text == it.next.text
+						// check same string instance
+						&& item.string != it.string
+						// check same string
+						&& !item.string.equals(it.string))
+					it = it.next;
+
+				// unify duplicate string :)
+				// Note: this is required for 'packing test' in prepare to work! 
+				if (item.string != it.string && item.string.equals(it.string))
+					item.string = it.string;
+
+				// insert after text of same type and/or before same string
 				item.next = it.next;
 				it.next = item;
-
 				return;
 			}
 		}
 
 		item.next = labels;
 		labels = item;
+		//		for (it = labels; it != null; it = it.next)
+		//			Log.d(TAG, "> " + it.text + " " + it.string);
+		//		Log.d(TAG, "< ");
 	}
 
 	@Override
@@ -94,19 +113,14 @@ public final class TextLayer extends TextureLayer {
 		if (TextureRenderer.debug)
 			Log.d("...", "prepare");
 
-		// int numLabel = 0;
-		// int numTextures = 0;
-
 		short numIndices = 0;
 		short offsetIndices = 0;
 
-		curItem = VertexPool.get();
+		VertexPoolItem vi = pool = VertexPool.get();
-		pool = curItem;
+		int pos = vi.used; // 0
+		short buf[] = vi.vertices;
 
-		VertexPoolItem si = curItem;
+		verticesCnt = 0;
-
-		int pos = si.used;
-		short buf[] = si.vertices;
 
 		int advanceY = 0;
 		float x = 0;
@@ -117,8 +131,7 @@ public final class TextLayer extends TextureLayer {
 		textures = to;
 		mCanvas.setBitmap(to.bitmap);
 
-		for (TextItem it = labels; it != null; it = it.next) {
+		for (TextItem it = labels; it != null;) {
-			// numLabel++;
 
 			float width = it.width + 2 * mFontPadX;
 			float height = (int) (it.text.fontHeight) + 2 * mFontPadY + 0.5f;
@@ -165,6 +178,34 @@ public final class TextLayer extends TextureLayer {
 			float hw = width / 2.0f;
 			float hh = height / 2.0f;
 
+			float hh2 = 0;
+			if (!it.text.caption) {
+				hw /= mScale;
+				hh2 = hh + it.text.fontDescent / 2;
+				hh -= it.text.fontDescent / 2;
+				hh /= mScale;
+				hh2 /= mScale;
+			}
+
+			// texture coordinates
+			short u1 = (short) (SCALE * x);
+			short v1 = (short) (SCALE * y);
+			short u2 = (short) (SCALE * (x + width));
+			short v2 = (short) (SCALE * (y + height));
+
+			// add symbol items referencing the same bitmap / drawable
+			for (TextItem it2 = it;; it2 = it2.next) {
+
+				if (it != it2) {
+					if (it2 == null
+							|| (it2.text != it.text)
+							|| (it2.string != it.string)) {
+						it = it2;
+						break;
+					}
+					//Log.d(TAG, "pack strings: " + it.string);
+				}
+
 				short x1, x2, x3, x4, y1, y3, y2, y4;
 
 				if (it.text.caption) {
@@ -175,8 +216,8 @@ public final class TextLayer extends TextureLayer {
 					// x1 = x3 = (short) (0);
 					// x2 = x4 = (short) (SCALE * width);
 				} else {
-				float vx = it.x1 - it.x2;
+					float vx = it2.x1 - it2.x2;
-				float vy = it.y1 - it.y2;
+					float vy = it2.y1 - it2.y2;
 					float a = (float) Math.sqrt(vx * vx + vy * vy);
 					vx = vx / a;
 					vy = vy / a;
@@ -184,13 +225,6 @@ public final class TextLayer extends TextureLayer {
 					float ux = -vy;
 					float uy = vx;
 
-				hw /= mScale;
-				float hh2 = hh + it.text.fontDescent / 2;
-				hh -= it.text.fontDescent / 2;
-
-				hh /= mScale;
-				hh2 /= mScale;
-
 					x1 = (short) (SCALE * (vx * hw - ux * hh));
 					y1 = (short) (SCALE * (vy * hw - uy * hh));
 					x2 = (short) (SCALE * (-vx * hw - ux * hh));
@@ -201,16 +235,17 @@ public final class TextLayer extends TextureLayer {
 					y3 = (short) (SCALE * (vy * hw + uy * hh2));
 				}
 
-			short u1 = (short) (SCALE * x);
-			short v1 = (short) (SCALE * y);
-			short u2 = (short) (SCALE * (x + width));
-			short v2 = (short) (SCALE * (y + height));
-
 				// add vertices
-			int tmp = (int) (SCALE * it.x) & LBIT_MASK;
+				int tmp = (int) (SCALE * it2.x) & LBIT_MASK;
-			short tx = (short) (tmp | (it.text.caption ? 1 : 0));
+				short tx = (short) (tmp | (it2.text.caption ? 1 : 0));
+				short ty = (short) (SCALE * it2.y);
 
-			short ty = (short) (SCALE * it.y);
+				if (pos == VertexPoolItem.SIZE) {
+					vi.used = VertexPoolItem.SIZE;
+					vi = vi.next = VertexPool.get();
+					buf = vi.vertices;
+					pos = 0;
+				}
 
 				// top-left
 				buf[pos++] = tx;
@@ -242,14 +277,8 @@ public final class TextLayer extends TextureLayer {
 				buf[pos++] = v1;
 
 				// six indices to draw the four vertices
-			numIndices += 6;
+				numIndices += TextureRenderer.INDICES_PER_SPRITE;
-
+				verticesCnt += 4;
-			if (pos == VertexPoolItem.SIZE) {
-				si.used = VertexPoolItem.SIZE;
-				si = si.next = VertexPool.get();
-				buf = si.vertices;
-				pos = 0;
-			}
 
 				// FIXME this does not work, need to draw bitmap on next
 				// texture...
@@ -259,15 +288,15 @@ public final class TextLayer extends TextureLayer {
 				// pos = 0;
 				// }
 
+			}
 			x += width;
 		}
 
+		vi.used = pos;
+
 		to.offset = offsetIndices;
 		to.vertices = (short) (numIndices - offsetIndices);
 
-		si.used = pos;
-		curItem = si;
-
 		//	Log.d(TAG, "added labels " + numTextures + " " + numLabel);
 
 		return true;
@@ -277,8 +306,10 @@ public final class TextLayer extends TextureLayer {
 	protected void clear() {
 		TextureObject.release(textures);
 		TextItem.release(labels);
+		VertexPool.release(pool);
 		textures = null;
 		labels = null;
+		pool = null;
 		verticesCnt = 0;
 	}
 }

src/org/oscim/renderer/overlays/TextOverlay.java

@@ -38,8 +38,11 @@ public class TextOverlay extends RenderOverlay {
 	private LabelThread mThread;
 
 	private MapPosition mWorkPos;
+
+	// TextLayer that is updating
 	private TextLayer mWorkLayer;
-	private TextLayer mNewLayer;
+	// TextLayer that is ready to be added to 'layers'
+	private TextLayer mCurLayer;
 
 	/* package */boolean mRun;
 	/* package */boolean mRerun;
@@ -97,8 +100,9 @@ public class TextOverlay extends RenderOverlay {
 
 		// only relabel when tiles belong to the current zoomlevel or its parent
 		if (diff > 1 || diff < -2) {
+			// pass back the current layer
 			synchronized (this) {
-				mNewLayer = tl;
+				mCurLayer = tl;
 			}
 			return;
 		}
@@ -257,7 +261,7 @@ public class TextOverlay extends RenderOverlay {
 
 		// everything synchronized?
 		synchronized (this) {
-			mNewLayer = tl;
+			mCurLayer = tl;
 		}
 	}
 
@@ -268,14 +272,17 @@ public class TextOverlay extends RenderOverlay {
 		if (mHolding)
 			return;
 
-		if (mNewLayer != null) {
+		if (mCurLayer != null) {
-
+			// keep text layer, not recrating its canvas each time
-			// keep text layer, not recrating its canvas each time...
 			mWorkLayer = (TextLayer) layers.textureLayers;
+
+			// clear textures and text items from previous layer
 			layers.clear();
 
-			layers.textureLayers = mNewLayer;
+			// set new TextLayer to be uploaded and used
-			mNewLayer = null;
+			layers.textureLayers = mCurLayer;
+
+			mCurLayer = null;
 
 			// make the 'labeled' MapPosition current
 			MapPosition tmp = mMapPosition;