Version 14, October 2012

[GpsPrune.git] / tim / prune / gui / map / MapPosition.java

diff --git a/tim/prune/gui/map/MapPosition.java b/tim/prune/gui/map/MapPosition.java
index d035f10bb3f8bd74ddff6959e13e2a20bfdd1c36..25f05fc1a2a238370d8888ea4b807b7d3f5f8adb 100644 (file)
--- a/tim/prune/gui/map/MapPosition.java
+++ b/tim/prune/gui/map/MapPosition.java
@@ -9,9 +9,9 @@ public class MapPosition
        private static final int MAP_TILE_SIZE = 256;
 
        /** x position (scale depends on zoom) */
-       private long _xPosition = 0L;
+       private int _xPosition = 0;
        /** y position (scale depends on zoom) */
-       private long _yPosition = 0L;
+       private int _yPosition = 0;
 
        /** Zoom level, from 2 to max */
        private int _zoom = 12;
@@ -48,12 +48,21 @@ public class MapPosition
                }
                if (requiredZoom < 2) requiredZoom = 2;
                // Set position
-               _zoom = requiredZoom;
-               _zoomFactor = 1 << _zoom;
+               setZoom(requiredZoom);
                _xPosition = transformToPixels((inMinX + inMaxX) / 2.0);
                _yPosition = transformToPixels((inMinY + inMaxY) / 2.0);
        }
 
+       /**
+        * Ensure that zoom and zoomFactor remain in sync
+        * @param inZoom zoom level to set
+        */
+       private void setZoom(int inZoom)
+       {
+               _zoom = inZoom;
+               _zoomFactor = 1 << _zoom;
+       }
+
        /**
         * Zoom and pan to show the selected area
         * @param inMinX minimum pixels X
@@ -80,8 +89,7 @@ public class MapPosition
                                break;
                        }
                }
-               _zoom = requiredZoom;
-               _zoomFactor = 1 << _zoom;
+               setZoom(requiredZoom);
                // Set position
                _xPosition = (_xPosition - inWidth/2 + (inMinX + inMaxX) / 2) * multFactor;
                _yPosition = (_yPosition - inHeight/2 + (inMinY + inMaxY) / 2) * multFactor;
@@ -92,7 +100,7 @@ public class MapPosition
         * @param inValue value to transform
         * @return pixels
         */
-       private long transformToPixels(double inValue)
+       private int transformToPixels(double inValue)
        {
                return transformToPixels(inValue, _zoom);
        }
@@ -103,9 +111,9 @@ public class MapPosition
         * @param inZoom zoom value to use
         * @return pixels
         */
-       private static long transformToPixels(double inValue, int inZoom)
+       private static int transformToPixels(double inValue, int inZoom)
        {
-               return (long) (inValue * MAP_TILE_SIZE * (1 << inZoom));
+               return (int) (inValue * MAP_TILE_SIZE * (1 << inZoom));
        }
 
        /**
@@ -137,7 +145,7 @@ public class MapPosition
         */
        public int getXFromCentre(double inValue)
        {
-               return (int) (transformToPixels(inValue) - _xPosition);
+               return transformToPixels(inValue) - _xPosition;
        }
 
        /**
@@ -147,7 +155,7 @@ public class MapPosition
         */
        public int getYFromCentre(double inValue)
        {
-               return (int) (transformToPixels(inValue) - _yPosition);
+               return transformToPixels(inValue) - _yPosition;
        }
 
        /**
@@ -209,19 +217,19 @@ public class MapPosition
         * @param inPosition position of point
         * @return tile index for that point
         */
-       private int getTileIndex(long inPosition)
+       private int getTileIndex(int inPosition)
        {
-               return (int) (inPosition / MAP_TILE_SIZE);
+               return inPosition / MAP_TILE_SIZE;
        }
 
        /**
         * @param inPosition position of point
         * @return pixel offset for that point
         */
-       private int getDisplayOffset(long inPosition)
+       private int getDisplayOffset(int inPosition)
        {
-               return (int) (inPosition % MAP_TILE_SIZE);
-               // Maybe >> 8 would be slightly faster?
+               return inPosition % MAP_TILE_SIZE;
+               // I thought that &255 would be slightly faster, but it gives the wrong result
        }
 
        /**
@@ -231,8 +239,7 @@ public class MapPosition
        {
                if (_zoom < MAX_ZOOM)
                {
-                       _zoom++;
-                       _zoomFactor = 1 << _zoom;
+                       setZoom(_zoom + 1);
                        _xPosition *= 2;
                        _yPosition *= 2;
                }
@@ -243,10 +250,9 @@ public class MapPosition
         */
        public void zoomOut()
        {
-               if (_zoom >= 2)
+               if (_zoom >= 3)
                {
-                       _zoom--;
-                       _zoomFactor = 1 << _zoom;
+                       setZoom(_zoom - 1);
                        _xPosition /= 2;
                        _yPosition /= 2;
                }