Moved source into separate src directory due to popular request

[GpsPrune.git] / src / tim / prune / gui / Viewport.java

diff --git a/src/tim/prune/gui/Viewport.java b/src/tim/prune/gui/Viewport.java
new file mode 100644 (file)
index 0000000..25eba2f
--- /dev/null
+++ b/src/tim/prune/gui/Viewport.java
@@ -0,0 +1,43 @@
+package tim.prune.gui;
+
+import tim.prune.gui.map.MapCanvas;
+import tim.prune.gui.map.MapPosition;
+import tim.prune.gui.map.MapUtils;
+
+/**
+ * Class to provide access to current viewport
+ * The point of this class is to decouple the view from the MapCanvas object
+ * so that when the GetGpsies function needs to know the area currently viewed, it doesn't
+ * need to have a direct connection to the MapCanvas.  Instead it asks the App for the viewport,
+ * which is then able to get the map position from the MapCanvas.
+ * I'm still not sure whether this is ugly or not, but it's more efficient than constantly listening.
+ */
+public class Viewport
+{
+       /** Map canvas object */
+       private MapCanvas _mapCanvas = null;
+
+       /**
+        * Constructor
+        * @param inCanvas map canvas object
+        */
+       public Viewport(MapCanvas inCanvas)
+       {
+               _mapCanvas = inCanvas;
+       }
+
+       /**
+        * @return coordinate bounds of current viewport
+        */
+       public double[] getBounds()
+       {
+               int width = _mapCanvas.getWidth();
+               int height = _mapCanvas.getHeight();
+               MapPosition mapPosition = _mapCanvas.getMapPosition();
+               double minLat = MapUtils.getLatitudeFromY(mapPosition.getYFromPixels(height, height));
+               double maxLat = MapUtils.getLatitudeFromY(mapPosition.getYFromPixels(0, height));
+               double minLon = MapUtils.getLongitudeFromX(mapPosition.getXFromPixels(0, width));
+               double maxLon = MapUtils.getLongitudeFromX(mapPosition.getXFromPixels(width, width));
+               return new double[] {minLat, minLon, maxLat, maxLon};
+       }
+}