(svn r6721) -Codechange: some comments, aligning, types and variable localization.

viewport.h

@@ -71,7 +71,8 @@ enum {
 void VpSelectTilesWithMethod(int x, int y, int method);
 
 // highlighting draw styles
-enum {
+typedef byte HighLightStyle;
+enum HighLightStyles {
 	HT_NONE   = 0x00,
 	HT_RECT   = 0x80,
 	HT_POINT  = 0x40,
@@ -79,15 +80,17 @@ enum {
 	                   * (uses lower bits to indicate direction) */
 	HT_RAIL   = 0x10, /* autorail (one piece)
 	                  * (uses lower bits to indicate direction) */
+	HT_DRAG_MASK = 0xF0, ///< masks the drag-type
 
 	/* lower bits (used with HT_LINE and HT_RAIL):
 	 * (see ASCII art in autorail.h for a visual interpretation) */
-	HT_DIR_X  = 0,  // X direction
-	HT_DIR_Y  = 1,  // Y direction
-	HT_DIR_HU = 2, // horizontal upper
-	HT_DIR_HL = 3, // horizontal lower
-	HT_DIR_VL = 4, // vertical left
-	HT_DIR_VR = 5, // vertical right
+	HT_DIR_X  = 0,    ///< X direction
+	HT_DIR_Y  = 1,    ///< Y direction
+	HT_DIR_HU = 2,    ///< horizontal upper
+	HT_DIR_HL = 3,    ///< horizontal lower
+	HT_DIR_VL = 4,    ///< vertical left
+	HT_DIR_VR = 5,    ///< vertical right
+	HT_DIR_MASK = 0x7 ///< masks the drag-direction
 };
 
 typedef struct TileHighlightData {