(svn r11661) -Codechange: some header reworks in order to try to reduce the compile time of OpenTTD by reduce the amount of circular-ish dependencies.

src/direction_type.h

@@ -0,0 +1,122 @@
+/* $Id$ */
+
+/** @file direction_type.h Different types to 'show' directions. */
+
+#ifndef DIRECTION_TYPE_H
+#define DIRECTION_TYPE_H
+
+#include "core/enum_type.hpp"
+
+/**
+ * Defines the 8 directions on the map.
+ *
+ * This enum defines 8 possible directions which are used for
+ * the vehicles in the game. The directions are aligned straight
+ * to the viewport, not to the map. So north points to the top of
+ * your viewport and not rotated by 45 degrees left or right to get
+ * a "north" used in you games.
+ */
+enum Direction {
+	DIR_BEGIN = 0,          ///< Used to iterate
+	DIR_N   = 0,            ///< North
+	DIR_NE  = 1,            ///< Northeast
+	DIR_E   = 2,            ///< East
+	DIR_SE  = 3,            ///< Southeast
+	DIR_S   = 4,            ///< South
+	DIR_SW  = 5,            ///< Southwest
+	DIR_W   = 6,            ///< West
+	DIR_NW  = 7,            ///< Northwest
+	DIR_END,                ///< Used to iterate
+	INVALID_DIR = 0xFF,     ///< Flag for an invalid direction
+};
+
+/** Define basic enum properties */
+template <> struct EnumPropsT<Direction> : MakeEnumPropsT<Direction, byte, DIR_BEGIN, DIR_END, INVALID_DIR> {};
+typedef TinyEnumT<Direction> DirectionByte; //typedefing-enumification of Direction
+
+
+/**
+ * Enumeration for the difference between two directions.
+ *
+ * This enumeration is used to mark differences between
+ * two directions. If you get one direction you can align
+ * a second direction in 8 different ways. This enumeration
+ * only contains 6 of these 8 differences, but the remaining
+ * two can be calculated by adding to differences together.
+ * This also means you can add two differences together and
+ * get the difference you really want to get. The difference
+ * of 45 degrees left + the difference of 45 degrees right results in the
+ * difference of 0 degrees.
+ *
+ * @note To get this mentioned addition of direction you must use
+ *       modulo DIR_END or use the #ChangeDirDiff(DirDiff, DirDiff) function.
+ * @see ChangeDirDiff(DirDiff, DirDiff)
+ */
+enum DirDiff {
+	DIRDIFF_SAME    = 0,    ///< Both directions faces to the same direction
+	DIRDIFF_45RIGHT = 1,    ///< Angle of 45 degrees right
+	DIRDIFF_90RIGHT = 2,    ///< Angle of 90 degrees right
+	DIRDIFF_REVERSE = 4,    ///< One direction is the opposit of the other one
+	DIRDIFF_90LEFT  = 6,    ///< Angle of 90 degrees left
+	DIRDIFF_45LEFT  = 7     ///< Angle of 45 degrees left
+};
+
+
+/**
+ * Enumeration for diagonal directions.
+ *
+ * This enumeration is used for the 4 direction of the tile-edges.
+ */
+enum DiagDirection {
+	DIAGDIR_BEGIN = 0,      ///< Used for iterations
+	DIAGDIR_NE  = 0,        ///< Northeast, upper right on your monitor
+	DIAGDIR_SE  = 1,        ///< Southeast
+	DIAGDIR_SW  = 2,        ///< Southwest
+	DIAGDIR_NW  = 3,        ///< Northwest
+	DIAGDIR_END,            ///< Used for iterations
+	INVALID_DIAGDIR = 0xFF, ///< Flag for an invalid DiagDirection
+};
+
+DECLARE_POSTFIX_INCREMENT(DiagDirection);
+
+/** Define basic enum properties */
+template <> struct EnumPropsT<DiagDirection> : MakeEnumPropsT<DiagDirection, byte, DIAGDIR_BEGIN, DIAGDIR_END, INVALID_DIAGDIR> {};
+typedef TinyEnumT<DiagDirection> DiagDirectionByte; //typedefing-enumification of DiagDirection
+
+
+/**
+ * Enumeration for the difference between to DiagDirection.
+ *
+ * As the DiagDirection only contains 4 possible directions the
+ * difference between two of these directions can only be in 4 ways.
+ * As the DirDiff enumeration the values can be added together and
+ * you will get the resulting difference (use modulo DIAGDIR_END).
+ *
+ * @see DirDiff
+ */
+enum DiagDirDiff {
+	DIAGDIRDIFF_SAME    = 0,        ///< Same directions
+	DIAGDIRDIFF_90RIGHT = 1,        ///< 90 degrees right
+	DIAGDIRDIFF_REVERSE = 2,        ///< Reverse directions
+	DIAGDIRDIFF_90LEFT  = 3         ///< 90 degrees left
+};
+
+/** Allow incrementing of DiagDirDiff variables */
+DECLARE_POSTFIX_INCREMENT(DiagDirDiff);
+
+
+/**
+ * Enumeration for the two axis X and Y
+ *
+ * This enumeration represente the two axis X and Y in the game.
+ * The X axis is the one which goes align the north-west edge
+ * (and south-east edge). The Y axis must be so the one which goes
+ * align the north-east edge (and south-west) edge.
+ */
+enum Axis {
+	AXIS_X = 0,     ///< The X axis
+	AXIS_Y = 1,     ///< The y axis
+	AXIS_END        ///< Used for iterations
+};
+
+#endif /* DIRECTION_TYPE_H */