POT textures #334 improvements and samples

docs/Changelog.md

@@ -7,6 +7,7 @@
 - Osmagray theme [#300](https://github.com/mapsforge/vtm/issues/300)
 - Symbol rotation [#294](https://github.com/mapsforge/vtm/issues/294)
 - Location custom shaders & improvements [#317](https://github.com/mapsforge/vtm/issues/317) [#321](https://github.com/mapsforge/vtm/issues/321)
+- POT textures [#334](https://github.com/mapsforge/vtm/issues/334)
 - OkHttp external cache [#135](https://github.com/mapsforge/vtm/issues/135)
 - Texture atlas improvements [#301](https://github.com/mapsforge/vtm/pull/301) [#304](https://github.com/mapsforge/vtm/pull/304)
 - vtm-ios-example module [#326](https://github.com/mapsforge/vtm/issues/326)

vtm-android-example/AndroidManifest.xml

@@ -33,7 +33,7 @@
             android:name=".AtlasMultiTextureActivity"
             android:configChanges="keyboardHidden|orientation|screenSize" />
         <activity
-            android:name=".AtlasThemeMapActivity"
+            android:name=".AtlasThemeActivity"
             android:configChanges="keyboardHidden|orientation|screenSize" />
         <activity
             android:name=".BitmapTileMapActivity"
@@ -86,6 +86,9 @@
         <activity
             android:name=".PathOverlayActivity"
             android:configChanges="keyboardHidden|orientation|screenSize" />
+        <activity
+            android:name=".POTTextureActivity"
+            android:configChanges="keyboardHidden|orientation|screenSize" />
         <activity
             android:name=".RotateMarkerOverlayActivity"
             android:configChanges="keyboardHidden|orientation|screenSize" />

vtm-android-example/src/org/oscim/android/test/AtlasThemeActivity.java

@@ -19,7 +19,7 @@ import android.os.Bundle;
 
 import org.oscim.theme.ThemeLoader;
 
-public class AtlasThemeMapActivity extends SimpleMapActivity {
+public class AtlasThemeActivity extends SimpleMapActivity {
 
     @Override
     public void onCreate(Bundle savedInstanceState) {

vtm-android-example/src/org/oscim/android/test/POTTextureActivity.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2017 devemux86
+ *
+ * This program is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.oscim.android.test;
+
+import android.os.Bundle;
+
+import org.oscim.theme.ThemeLoader;
+
+public class POTTextureActivity extends SimpleMapActivity {
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        ThemeLoader.POT_TEXTURES = true;
+
+        super.onCreate(savedInstanceState);
+    }
+}

vtm-android-example/src/org/oscim/android/test/Samples.java

@@ -43,10 +43,13 @@ public class Samples extends Activity {
         LinearLayout linearLayout = (LinearLayout) findViewById(R.id.samples);
         linearLayout.addView(createButton(SimpleMapActivity.class));
         linearLayout.addView(createButton(MapsforgeMapActivity.class));
-        linearLayout.addView(createButton(MapsforgeStyleActivity.class));
         linearLayout.addView(createButton(MapboxMapActivity.class));
         linearLayout.addView(createButton(OsmJsonMapActivity.class));
-        linearLayout.addView(createButton(AtlasThemeMapActivity.class));
+
+        linearLayout.addView(createLabel("Vector Features"));
+        linearLayout.addView(createButton(MapsforgeStyleActivity.class));
+        linearLayout.addView(createButton(AtlasThemeActivity.class));
+        linearLayout.addView(createButton(POTTextureActivity.class));
 
         linearLayout.addView(createLabel("Raster Maps"));
         linearLayout.addView(createButton(BitmapTileMapActivity.class));

vtm-android/src/org/oscim/android/canvas/AndroidCanvas.java

@@ -60,18 +60,18 @@ public class AndroidCanvas implements Canvas {
     }
 
     @Override
-    public void drawBitmap(Bitmap bitmap) {
+    public void drawBitmap(Bitmap bitmap, float x, float y) {
+        canvas.drawBitmap(((AndroidBitmap) bitmap).mBitmap, x, y, null);
+    }
+
+    @Override
+    public void drawBitmapScaled(Bitmap bitmap) {
         android.graphics.Bitmap scaledBitmap = android.graphics.Bitmap.createScaledBitmap(
                 ((AndroidBitmap) bitmap).mBitmap, canvas.getWidth(), canvas.getHeight(), true);
         canvas.drawBitmap(scaledBitmap, 0, 0, null);
         scaledBitmap.recycle();
     }
 
-    @Override
-    public void drawBitmap(Bitmap bitmap, float x, float y) {
-        canvas.drawBitmap(((AndroidBitmap) bitmap).mBitmap, x, y, null);
-    }
-
     @Override
     public void drawCircle(float x, float y, float radius, Paint paint) {
         canvas.drawCircle(x, y, radius, ((AndroidPaint) paint).mPaint);

vtm-desktop/src/org/oscim/awt/AwtCanvas.java

@@ -128,12 +128,6 @@ public class AwtCanvas implements Canvas {
         }
     }
 
-    @Override
-    public void drawBitmap(Bitmap bitmap) {
-        Image scaledImage = ((AwtBitmap) bitmap).bitmap.getScaledInstance(this.bitmap.getWidth(), this.bitmap.getHeight(), Image.SCALE_DEFAULT);
-        this.canvas.drawImage(scaledImage, 0, 0, this.bitmap.getWidth(), this.bitmap.getHeight(), null);
-    }
-
     @Override
     public void drawBitmap(Bitmap bitmap, float x, float y) {
         BufferedImage src = ((AwtBitmap) bitmap).bitmap;
@@ -153,6 +147,12 @@ public class AwtCanvas implements Canvas {
             this.canvas.drawImage(src, (int) x, (int) y, null);
     }
 
+    @Override
+    public void drawBitmapScaled(Bitmap bitmap) {
+        Image scaledImage = ((AwtBitmap) bitmap).bitmap.getScaledInstance(this.bitmap.getWidth(), this.bitmap.getHeight(), Image.SCALE_DEFAULT);
+        this.canvas.drawImage(scaledImage, 0, 0, this.bitmap.getWidth(), this.bitmap.getHeight(), null);
+    }
+
     @Override
     public void drawCircle(float x, float y, float radius, Paint paint) {
         AwtPaint awtPaint = (AwtPaint) paint;

vtm-ios-example/src/org/oscim/ios/test/IOSLineTexTest.java

@@ -34,8 +34,8 @@ import org.oscim.layers.vector.geometries.Style;
 import org.oscim.map.Map;
 import org.oscim.renderer.bucket.TextureItem;
 import org.oscim.theme.VtmThemes;
-import org.oscim.theme.XmlThemeBuilder;
 import org.oscim.tiling.source.oscimap4.OSciMap4TileSource;
+import org.oscim.utils.Utils;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -63,7 +63,7 @@ public class IOSLineTexTest extends GdxMap {
 
         mMap.setMapPosition(0, 0, 1 << 2);
 
-        tex = XmlThemeBuilder.loadTexture("", "patterns/pike.png", 0, 0, 100);
+        tex = Utils.loadTexture("", "patterns/pike.png", 0, 0, 100);
 //        tex = new TextureItem(CanvasAdapter.getBitmapAsset("", "patterns/pike.png"));
         tex.mipmap = true;
 

vtm-ios/src/org/oscim/ios/backend/IosCanvas.java

@@ -83,15 +83,6 @@ public class IosCanvas implements Canvas {
         iosFill.drawLine(this.cgBitmapContext, string, x, y);
     }
 
-    @Override
-    public void drawBitmap(Bitmap bitmap) {
-        CGRect rect = new CGRect(0, 0, this.cgBitmapContext.getWidth(), this.cgBitmapContext.getHeight());
-        this.cgBitmapContext.saveGState();
-        this.cgBitmapContext.translateCTM(0, 0);
-        this.cgBitmapContext.drawImage(rect, ((IosBitmap) bitmap).cgBitmapContext.toImage());
-        this.cgBitmapContext.restoreGState();
-    }
-
     @Override
     public void drawBitmap(Bitmap bitmap, float x, float y) {
         this.cgBitmapContext.saveGState();
@@ -101,6 +92,15 @@ public class IosCanvas implements Canvas {
         this.cgBitmapContext.restoreGState();
     }
 
+    @Override
+    public void drawBitmapScaled(Bitmap bitmap) {
+        CGRect rect = new CGRect(0, 0, this.cgBitmapContext.getWidth(), this.cgBitmapContext.getHeight());
+        this.cgBitmapContext.saveGState();
+        this.cgBitmapContext.translateCTM(0, 0);
+        this.cgBitmapContext.drawImage(rect, ((IosBitmap) bitmap).cgBitmapContext.toImage());
+        this.cgBitmapContext.restoreGState();
+    }
+
     @Override
     public void drawCircle(float x, float y, float radius, Paint paint) {
         CGRect rect = new CGRect(x - radius, y - radius, x + radius, y + radius);

vtm-playground/src/org/oscim/test/MapsforgeLine_NPOT_Test.java

@@ -1,87 +0,0 @@
-/*
- * Copyright 2017 Longri
- *
- * This file is part of the OpenScienceMap project (http://www.opensciencemap.org).
- *
- * This program is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Lesser General Public License as published by the Free Software
- * Foundation, either version 3 of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
- * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License along with
- * this program. If not, see <http://www.gnu.org/licenses/>.
- */
-package org.oscim.test;
-
-import org.oscim.gdx.GdxMap;
-import org.oscim.gdx.GdxMapApp;
-import org.oscim.layers.TileGridLayer;
-import org.oscim.layers.tile.vector.VectorTileLayer;
-import org.oscim.renderer.BitmapRenderer;
-import org.oscim.renderer.GLViewport;
-import org.oscim.scalebar.DefaultMapScaleBar;
-import org.oscim.scalebar.ImperialUnitAdapter;
-import org.oscim.scalebar.MapScaleBar;
-import org.oscim.scalebar.MapScaleBarLayer;
-import org.oscim.scalebar.MetricUnitAdapter;
-import org.oscim.theme.VtmThemes;
-import org.oscim.tiling.source.mapfile.MapFileTileSource;
-
-import java.io.File;
-
-public class MapsforgeLine_NPOT_Test extends GdxMap {
-
-    private static File mapFile;
-
-    @Override
-    public void createLayers() {
-        MapFileTileSource tileSource = new MapFileTileSource();
-        tileSource.setMapFile(mapFile.getAbsolutePath());
-        tileSource.setPreferredLanguage("en");
-
-        VectorTileLayer l = mMap.setBaseMap(tileSource);
-        mMap.setTheme(VtmThemes.DEFAULT);
-        mMap.layers().add(new TileGridLayer(mMap));
-
-        DefaultMapScaleBar mapScaleBar = new DefaultMapScaleBar(mMap);
-        mapScaleBar.setScaleBarMode(DefaultMapScaleBar.ScaleBarMode.BOTH);
-        mapScaleBar.setDistanceUnitAdapter(MetricUnitAdapter.INSTANCE);
-        mapScaleBar.setSecondaryDistanceUnitAdapter(ImperialUnitAdapter.INSTANCE);
-        mapScaleBar.setScaleBarPosition(MapScaleBar.ScaleBarPosition.BOTTOM_LEFT);
-
-        MapScaleBarLayer mapScaleBarLayer = new MapScaleBarLayer(mMap, mapScaleBar);
-        BitmapRenderer renderer = mapScaleBarLayer.getRenderer();
-        renderer.setPosition(GLViewport.Position.BOTTOM_LEFT);
-        renderer.setOffset(5, 0);
-        mMap.layers().add(mapScaleBarLayer);
-
-        //https://www.google.de/maps/@52.5808431,13.4000501,19.5z
-        mMap.setMapPosition(52.5808431, 13.4000501, 1 << 21);
-    }
-
-    private static File getMapFile(String[] args) {
-        if (args.length == 0) {
-            throw new IllegalArgumentException("missing argument: <mapFile>");
-        }
-
-        File file = new File(args[0]);
-        if (!file.exists()) {
-            throw new IllegalArgumentException("file does not exist: " + file);
-        } else if (!file.isFile()) {
-            throw new IllegalArgumentException("not a file: " + file);
-        } else if (!file.canRead()) {
-            throw new IllegalArgumentException("cannot read file: " + file);
-        }
-        return file;
-    }
-
-    public static void main(String[] args) {
-        mapFile = getMapFile(args);
-
-        GdxMapApp.init();
-        GdxMapApp.run(new MapsforgeLine_NPOT_Test());
-    }
-}

vtm-playground/src/org/oscim/test/MapsforgeLine_POT_Test.java

@@ -1,90 +0,0 @@
-/*
- * Copyright 2017 Longri
- *
- * This file is part of the OpenScienceMap project (http://www.opensciencemap.org).
- *
- * This program is free software: you can redistribute it and/or modify it under the
- * terms of the GNU Lesser General Public License as published by the Free Software
- * Foundation, either version 3 of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
- * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License along with
- * this program. If not, see <http://www.gnu.org/licenses/>.
- */
-package org.oscim.test;
-
-import org.oscim.gdx.GdxMap;
-import org.oscim.gdx.GdxMapApp;
-import org.oscim.layers.TileGridLayer;
-import org.oscim.layers.tile.vector.VectorTileLayer;
-import org.oscim.renderer.BitmapRenderer;
-import org.oscim.renderer.GLViewport;
-import org.oscim.scalebar.DefaultMapScaleBar;
-import org.oscim.scalebar.ImperialUnitAdapter;
-import org.oscim.scalebar.MapScaleBar;
-import org.oscim.scalebar.MapScaleBarLayer;
-import org.oscim.scalebar.MetricUnitAdapter;
-import org.oscim.theme.ThemeLoader;
-import org.oscim.theme.VtmThemes;
-import org.oscim.tiling.source.mapfile.MapFileTileSource;
-
-import java.io.File;
-
-public class MapsforgeLine_POT_Test extends GdxMap {
-
-    private static File mapFile;
-
-    @Override
-    public void createLayers() {
-        ThemeLoader.POT_TEXTURES = true;
-
-        MapFileTileSource tileSource = new MapFileTileSource();
-        tileSource.setMapFile(mapFile.getAbsolutePath());
-        tileSource.setPreferredLanguage("en");
-
-        VectorTileLayer l = mMap.setBaseMap(tileSource);
-        mMap.setTheme(VtmThemes.DEFAULT);
-        mMap.layers().add(new TileGridLayer(mMap));
-
-        DefaultMapScaleBar mapScaleBar = new DefaultMapScaleBar(mMap);
-        mapScaleBar.setScaleBarMode(DefaultMapScaleBar.ScaleBarMode.BOTH);
-        mapScaleBar.setDistanceUnitAdapter(MetricUnitAdapter.INSTANCE);
-        mapScaleBar.setSecondaryDistanceUnitAdapter(ImperialUnitAdapter.INSTANCE);
-        mapScaleBar.setScaleBarPosition(MapScaleBar.ScaleBarPosition.BOTTOM_LEFT);
-
-        MapScaleBarLayer mapScaleBarLayer = new MapScaleBarLayer(mMap, mapScaleBar);
-        BitmapRenderer renderer = mapScaleBarLayer.getRenderer();
-        renderer.setPosition(GLViewport.Position.BOTTOM_LEFT);
-        renderer.setOffset(5, 0);
-        mMap.layers().add(mapScaleBarLayer);
-
-        //https://www.google.de/maps/@52.5808431,13.4000501,19.5z
-        mMap.setMapPosition(52.5808431, 13.4000501, 1 << 21);
-    }
-
-    private static File getMapFile(String[] args) {
-        if (args.length == 0) {
-            throw new IllegalArgumentException("missing argument: <mapFile>");
-        }
-
-        File file = new File(args[0]);
-        if (!file.exists()) {
-            throw new IllegalArgumentException("file does not exist: " + file);
-        } else if (!file.isFile()) {
-            throw new IllegalArgumentException("not a file: " + file);
-        } else if (!file.canRead()) {
-            throw new IllegalArgumentException("cannot read file: " + file);
-        }
-        return file;
-    }
-
-    public static void main(String[] args) {
-        mapFile = getMapFile(args);
-
-        GdxMapApp.init();
-        GdxMapApp.run(new MapsforgeLine_POT_Test());
-    }
-}

vtm-playground/src/org/oscim/test/POTTextureTest.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2017 Longri
+ * Copyright 2017 devemux86
+ *
+ * This file is part of the OpenScienceMap project (http://www.opensciencemap.org).
+ *
+ * This program is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.oscim.test;
+
+import org.oscim.gdx.GdxMapApp;
+import org.oscim.theme.ThemeLoader;
+
+public class POTTextureTest extends MapTest {
+
+    private POTTextureTest() {
+        ThemeLoader.POT_TEXTURES = true;
+    }
+
+    public static void main(String[] args) {
+        GdxMapApp.init();
+        GdxMapApp.run(new POTTextureTest());
+    }
+}

vtm-web/src/org/oscim/gdx/client/GwtCanvas.java

@@ -91,12 +91,12 @@ public class GwtCanvas implements org.oscim.backend.canvas.Canvas {
     }
 
     @Override
-    public void drawBitmap(Bitmap bitmap) {
+    public void drawBitmap(Bitmap bitmap, float x, float y) {
         // TODO
     }
 
     @Override
-    public void drawBitmap(Bitmap bitmap, float x, float y) {
+    public void drawBitmapScaled(Bitmap bitmap) {
         // TODO
     }
 

vtm/src/org/oscim/backend/canvas/Canvas.java

@@ -39,16 +39,16 @@ public interface Canvas {
      */
     void drawText(String string, float x, float y, Paint fill, Paint stroke);
 
-    /**
-     * Draw Bitmap to fill target by stretching.
-     */
-    void drawBitmap(Bitmap bitmap);
-
     /**
      * Draw Bitmap to Canvas.
      */
     void drawBitmap(Bitmap bitmap, float x, float y);
 
+    /**
+     * Draw scaled Bitmap to fill target.
+     */
+    void drawBitmapScaled(Bitmap bitmap);
+
     void drawCircle(float x, float y, float radius, Paint paint);
 
     void drawLine(float x1, float y1, float x2, float y2, Paint paint);

vtm/src/org/oscim/theme/XmlThemeBuilder.java

@@ -23,7 +23,6 @@ package org.oscim.theme;
 import org.oscim.backend.CanvasAdapter;
 import org.oscim.backend.XMLReaderAdapter;
 import org.oscim.backend.canvas.Bitmap;
-import org.oscim.backend.canvas.Canvas;
 import org.oscim.backend.canvas.Color;
 import org.oscim.backend.canvas.Paint.Cap;
 import org.oscim.backend.canvas.Paint.FontFamily;
@@ -31,7 +30,6 @@ import org.oscim.backend.canvas.Paint.FontStyle;
 import org.oscim.renderer.atlas.TextureAtlas;
 import org.oscim.renderer.atlas.TextureAtlas.Rect;
 import org.oscim.renderer.atlas.TextureRegion;
-import org.oscim.renderer.bucket.TextureItem;
 import org.oscim.theme.IRenderTheme.ThemeException;
 import org.oscim.theme.rule.Rule;
 import org.oscim.theme.rule.Rule.Closed;
@@ -50,7 +48,7 @@ import org.oscim.theme.styles.SymbolStyle;
 import org.oscim.theme.styles.SymbolStyle.SymbolBuilder;
 import org.oscim.theme.styles.TextStyle;
 import org.oscim.theme.styles.TextStyle.TextBuilder;
-import org.oscim.utils.math.MathUtils;
+import org.oscim.utils.Utils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.xml.sax.Attributes;
@@ -561,7 +559,7 @@ public class XmlThemeBuilder extends DefaultHandler {
                 logUnknownAttribute(elementName, name, value, i);
         }
 
-        b.texture = loadTexture(mTheme.getRelativePathPrefix(), src, b.symbolWidth, b.symbolHeight, b.symbolPercent);
+        b.texture = Utils.loadTexture(mTheme.getRelativePathPrefix(), src, b.symbolWidth, b.symbolHeight, b.symbolPercent);
         /*if (b.texture != null)
             b.texture.mipmap = true;*/
 
@@ -654,40 +652,11 @@ public class XmlThemeBuilder extends DefaultHandler {
                 logUnknownAttribute(elementName, name, value, i);
         }
 
-        b.texture = loadTexture(mTheme.getRelativePathPrefix(), src, b.symbolWidth, b.symbolHeight, b.symbolPercent);
+        b.texture = Utils.loadTexture(mTheme.getRelativePathPrefix(), src, b.symbolWidth, b.symbolHeight, b.symbolPercent);
 
         return b.build();
     }
 
-    public static TextureItem loadTexture(String relativePathPrefix, String src, int width, int height, int percent) {
-        if (src == null || src.length() == 0)
-            return null;
-
-        try {
-            Bitmap bitmap = CanvasAdapter.getBitmapAsset(relativePathPrefix, src, width, height, percent);
-            if (bitmap != null) {
-                log.debug("loading {}", src);
-
-                if (ThemeLoader.POT_TEXTURES) {
-                    int potWidth = MathUtils.nextPowerOfTwo(bitmap.getWidth());
-                    int potHeight = MathUtils.nextPowerOfTwo(bitmap.getHeight());
-                    if (potWidth != bitmap.getWidth() || potHeight != bitmap.getHeight()) {
-                        log.debug("POT texture: {}x{} -> {}x{}", bitmap.getWidth(), bitmap.getHeight(), potWidth, potHeight);
-                        Bitmap potBitmap = CanvasAdapter.newBitmap(potWidth, potHeight, 0);
-                        Canvas canvas = CanvasAdapter.newCanvas();
-                        canvas.setBitmap(potBitmap);
-                        canvas.drawBitmap(bitmap);
-                        bitmap = potBitmap;
-                    }
-                }
-                return new TextureItem(bitmap, true);
-            }
-        } catch (Exception e) {
-            log.debug("missing file / {}", e.getMessage());
-        }
-        return null;
-    }
-
     private LineStyle createOutline(String style, Attributes attributes) {
         if (style != null) {
             LineStyle line = (LineStyle) mStyles.get(OUTLINE_STYLE + style);

vtm/src/org/oscim/utils/Utils.java

@@ -1,5 +1,6 @@
 /*
- * Copyright 2016 devemux86
+ * Copyright 2016-2017 devemux86
+ * Copyright 2017 Longri
  *
  * This program is free software: you can redistribute it and/or modify it under the
  * terms of the GNU Lesser General Public License as published by the Free Software
@@ -14,8 +15,19 @@
  */
 package org.oscim.utils;
 
+import org.oscim.backend.CanvasAdapter;
+import org.oscim.backend.canvas.Bitmap;
+import org.oscim.backend.canvas.Canvas;
+import org.oscim.renderer.bucket.TextureItem;
+import org.oscim.theme.ThemeLoader;
+import org.oscim.utils.math.MathUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 public final class Utils {
 
+    private static final Logger log = LoggerFactory.getLogger(Utils.class);
+
     /**
      * Null safe equals.
      */
@@ -23,6 +35,38 @@ public final class Utils {
         return (o1 == o2) || (o1 != null && o1.equals(o2));
     }
 
+    /**
+     * Load a texture from a specified location and optional dimensions.
+     */
+    public static TextureItem loadTexture(String relativePathPrefix, String src, int width, int height, int percent) {
+        if (src == null || src.length() == 0)
+            return null;
+
+        try {
+            Bitmap bitmap = CanvasAdapter.getBitmapAsset(relativePathPrefix, src, width, height, percent);
+            if (bitmap != null) {
+                log.debug("loading {}", src);
+
+                if (ThemeLoader.POT_TEXTURES) {
+                    int potWidth = MathUtils.nextPowerOfTwo(bitmap.getWidth());
+                    int potHeight = MathUtils.nextPowerOfTwo(bitmap.getHeight());
+                    if (potWidth != bitmap.getWidth() || potHeight != bitmap.getHeight()) {
+                        log.debug("POT texture: {}x{} -> {}x{}", bitmap.getWidth(), bitmap.getHeight(), potWidth, potHeight);
+                        Bitmap potBitmap = CanvasAdapter.newBitmap(potWidth, potHeight, 0);
+                        Canvas canvas = CanvasAdapter.newCanvas();
+                        canvas.setBitmap(potBitmap);
+                        canvas.drawBitmapScaled(bitmap);
+                        bitmap = potBitmap;
+                    }
+                }
+                return new TextureItem(bitmap, true);
+            }
+        } catch (Exception e) {
+            log.debug("missing file / {}", e.getMessage());
+        }
+        return null;
+    }
+
     private Utils() {
         throw new IllegalStateException();
     }