Change TmxMapLoader to add y-direction awareness

You can now specify the direction of the y-axis at load time. The map will
be loaded accordingly, inverting objects or tiles as necessary. Thanks to
@PrinceManfred for getting this started.

diff --git a/gdx/src/com/badlogic/gdx/maps/tiled/TmxMapLoader.java b/gdx/src/com/badlogic/gdx/maps/tiled/TmxMapLoader.java
index 8512488..31270ad 100644 (file)
--- a/gdx/src/com/badlogic/gdx/maps/tiled/TmxMapLoader.java
+++ b/gdx/src/com/badlogic/gdx/maps/tiled/TmxMapLoader.java
@@ -17,17 +17,19 @@ import com.badlogic.gdx.files.FileHandle;
 import com.badlogic.gdx.graphics.Texture;
 import com.badlogic.gdx.graphics.g2d.TextureRegion;
 import com.badlogic.gdx.maps.ImageResolver;
+import com.badlogic.gdx.maps.ImageResolver.AssetManagerImageResolver;
+import com.badlogic.gdx.maps.ImageResolver.DirectImageResolver;
 import com.badlogic.gdx.maps.MapLayer;
 import com.badlogic.gdx.maps.MapObject;
 import com.badlogic.gdx.maps.MapProperties;
-import com.badlogic.gdx.maps.ImageResolver.AssetManagerImageResolver;
-import com.badlogic.gdx.maps.ImageResolver.DirectImageResolver;
 import com.badlogic.gdx.maps.objects.EllipseMapObject;
 import com.badlogic.gdx.maps.objects.PolygonMapObject;
 import com.badlogic.gdx.maps.objects.PolylineMapObject;
 import com.badlogic.gdx.maps.objects.RectangleMapObject;
 import com.badlogic.gdx.maps.tiled.TiledMapTileLayer.Cell;
 import com.badlogic.gdx.maps.tiled.tiles.StaticTiledMapTile;
+import com.badlogic.gdx.math.Polygon;
+import com.badlogic.gdx.math.Polyline;
 import com.badlogic.gdx.utils.Array;
 import com.badlogic.gdx.utils.Base64Coder;
 import com.badlogic.gdx.utils.GdxRuntimeException;
@@ -41,7 +43,8 @@ import com.badlogic.gdx.utils.XmlReader.Element;
 public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.Parameters> {
 
        public static class Parameters extends AssetLoaderParameters<TiledMap> {
-               
+               /** Whether to load the map for a y-up coordinate system */
+               boolean yUp = true;
        }
        
        protected static final int FLAG_FLIP_HORIZONTALLY = 0x80000000;
@@ -51,6 +54,10 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
        
        protected XmlReader xml = new XmlReader();
        protected Element root;
+       protected boolean yUp;
+
+       protected int mapWidthInPixels;
+       protected int mapHeightInPixels;
        
        public TmxMapLoader() {
                super(new InternalFileHandleResolver());
@@ -68,12 +75,26 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
        /**
         * Loads the {@link TiledMap} from the given file. The file is
         * resolved via the {@link FileHandleResolver} set in the constructor
-        * of this class. By default it will resolve to an internal file.
+        * of this class. By default it will resolve to an internal file. The
+        * map will be loaded for a y-up coordinate system.
         * @param fileName the filename
         * @return the TiledMap
         */
        public TiledMap load(String fileName) {
+               return load(fileName, true);
+       }
+
+       /**
+        * Loads the {@link TiledMap} from the given file. The file is
+        * resolved via the {@link FileHandleResolver} set in the constructor
+        * of this class. By default it will resolve to an internal file.
+        * @param fileName the filename
+        * @param yUp whether to load the map for a y-up coordinate system
+        * @return the TiledMap
+        */
+       public TiledMap load(String fileName, boolean yUp) {
                try {
+                       this.yUp = yUp;
                        FileHandle tmxFile = resolve(fileName);
                        root = xml.parse(tmxFile);
                        ObjectMap<String, Texture> textures = new ObjectMap<String, Texture>();
@@ -92,6 +113,11 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
        @Override
        public TiledMap load(AssetManager assetManager, String fileName, Parameters parameter) {
                FileHandle tmxFile = resolve(fileName);
+               if (parameter != null) {
+                       yUp = parameter.yUp;
+               } else {
+                       yUp = true;
+               }
                try {
                        return loadTilemap(root, tmxFile, new AssetManagerImageResolver(assetManager));
                } catch (Exception e) {
@@ -150,6 +176,8 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
                if (mapBackgroundColor != null) {
                        mapProperties.put("backgroundcolor", mapBackgroundColor);
                }
+               mapWidthInPixels = mapWidth * tileWidth;
+               mapHeightInPixels = mapHeight * tileHeight;
                
                Element properties = root.getChildByName("properties");
                if (properties != null) {
@@ -238,7 +266,11 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
                        
                        for (int y = margin; y <= stopHeight; y += tileheight + spacing) {
                                for (int x = margin; x <= stopWidth; x += tilewidth + spacing) {
-                                       TiledMapTile tile = new StaticTiledMapTile(new TextureRegion(texture, x, y, tilewidth, tileheight));
+                                       TextureRegion tileRegion = new TextureRegion(new TextureRegion(texture, x, y, tilewidth, tileheight));
+                                       if (!yUp) {
+                                               tileRegion.flip(false, true);
+                                       }
+                                       TiledMapTile tile = new StaticTiledMapTile(tileRegion);
                                        tile.setId(id);
                                        tileset.putTile(id++, tile);
                                }
@@ -317,7 +349,7 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
                                                                cell.setFlipVertically(flipVertically);
                                                        }
                                                        cell.setTile(tile);
-                                                       layer.setCell(x, height - 1 - y, cell);
+                                                       layer.setCell(x, yUp ? height - 1 - y : y, cell);
                                                }
                                        }
                                }
@@ -362,7 +394,7 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
                                                                                cell.setFlipVertically(flipVertically);
                                                                        }
                                                                        cell.setTile(tile);
-                                                                       layer.setCell(x, height - 1 - y, cell);
+                                                                       layer.setCell(x, yUp ? height - 1 - y : y, cell);
                                                                }
                                                        }
                                                }
@@ -412,7 +444,7 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
                                                                                        cell.setFlipVertically(flipVertically);
                                                                                }
                                                                                cell.setTile(tile);
-                                                                               layer.setCell(x, height - 1 - y, cell);
+                                                                               layer.setCell(x, yUp ? height - 1 - y : y, cell);
                                                                        }
                                                                } catch (IOException e) {
                                                                        throw new GdxRuntimeException("Error Reading TMX Layer Data.", e);
@@ -463,7 +495,7 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
                                                                                        cell.setFlipVertically(flipVertically);
                                                                                }
                                                                                cell.setTile(tile);
-                                                                               layer.setCell(x, height - 1 - y, cell);
+                                                                               layer.setCell(x, yUp ? height - 1 - y : y, cell);
                                                                        }
                        
                                                                } catch (DataFormatException e) {
@@ -505,8 +537,8 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
                        MapObject object = null;
                        
                        int x = element.getIntAttribute("x", 0);
-                       int y = element.getIntAttribute("y", 0);
-                       
+                       int y = (yUp ? mapHeightInPixels - element.getIntAttribute("y", 0) : element.getIntAttribute("y", 0));
+
                        int width = element.getIntAttribute("width", 0);
                        int height = element.getIntAttribute("height", 0);
                        
@@ -517,25 +549,35 @@ public class TmxMapLoader extends SynchronousAssetLoader<TiledMap, TmxMapLoader.
                                        float[] vertices = new float[points.length * 2];
                                        for (int i = 0; i < points.length; i++) {
                                                String[] point = points[i].split(",");
-                                               vertices[i * 2] = x + Integer.parseInt(point[0]);
-                                               vertices[i * 2 + 1] = y + Integer.parseInt(point[1]);
+                                               vertices[i * 2] = Integer.parseInt(point[0]);
+                                               vertices[i * 2 + 1] = Integer.parseInt(point[1]);
+                                               if (yUp) {
+                                                       vertices[i * 2 + 1] *= -1;
+                                               }
                                        }
-                                       object = new PolygonMapObject(vertices);
+                                       Polygon polygon = new Polygon(vertices);
+                                       polygon.setPosition(x, y);
+                                       object = new PolygonMapObject(polygon);
                                } else if ((child = element.getChildByName("polyline")) != null) {
                                        String[] points = child.getAttribute("points").split(" ");
                                        float[] vertices = new float[points.length * 2];
                                        for (int i = 0; i < points.length; i++) {
                                                String[] point = points[i].split(",");
-                                               vertices[i * 2] = x + Integer.parseInt(point[0]);
-                                               vertices[i * 2 + 1] = y + Integer.parseInt(point[1]);
+                                               vertices[i * 2] = Integer.parseInt(point[0]);
+                                               vertices[i * 2 + 1] = Integer.parseInt(point[1]);
+                                               if (yUp) {
+                                                       vertices[i * 2 + 1] *= -1;
+                                               }
                                        }
-                                       object = new PolylineMapObject(vertices);
+                                       Polyline polyline = new Polyline(vertices);
+                                       polyline.setPosition(x, y);
+                                       object = new PolylineMapObject(polyline);
                                } else if ((child = element.getChildByName("ellipse")) != null) {
-                                       object = new EllipseMapObject(x, y, width, height);
+                                       object = new EllipseMapObject(x, yUp ? y - height : y, width, height);
                                }
                        }
                        if (object == null) {
-                               object = new RectangleMapObject(x, y, width, height);
+                               object = new RectangleMapObject(x, yUp ? y - height : y, width, height);
                        }
                        object.setName(element.getAttribute("name", null));
                        String type = element.getAttribute("type", null);