byte array to save memory.

src/engine/InterestManagement/HeightMap.java

@@ -40,7 +40,7 @@ public class HeightMap {
 
     public static final HashMap<Integer, HeightMap> heightmapByLoadNum = new HashMap<>();
 
-    public static final HashMap<Integer, int[][]> _pixelData = new HashMap<>();
+    public static final HashMap<Integer, byte[][]> _pixelData = new HashMap<>();
 
     // Heightmap data for all zones.
     public static float SCALEVALUE = 1.0f / 255;
@@ -326,16 +326,16 @@ public class HeightMap {
                     try {
                         BufferedImage heightmapImage = ImageIO.read(imageFile);
 
-                        // Generate pixel for this heightmap.  RPG channels are all the same
+                        // Generate pixel data for this heightmap.  RPG channels are all the same
                         // in this greyscale TGA heightmap.  We will choose red.
 
-                        int[][] colorData = new int[heightmapImage.getWidth()][heightmapImage.getHeight()];
+                        byte[][] colorData = new byte[heightmapImage.getWidth()][heightmapImage.getHeight()];
 
                         for (int y = 0; y < heightmapImage.getHeight(); y++) {
                             for (int x = 0; x < heightmapImage.getWidth(); x++) {
 
                                 Color color = new Color(heightmapImage.getRGB(x, y));
-                                colorData[x][y] = color.getRed();
+                                colorData[x][y] = (byte) color.getRed();
                             }
                         }