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authorrubidium <rubidium@openttd.org>2007-08-03 12:10:07 +0000
committerrubidium <rubidium@openttd.org>2007-08-03 12:10:07 +0000
commit0f1992b932afa499599d638ab4f13c837d16903d (patch)
tree555d9fd2857a09a7994086e0ea1ef94bc4a30e02
parent616eb4134eac435bea86d738475f718309f7c5ea (diff)
downloadopenttd-0f1992b932afa499599d638ab4f13c837d16903d.tar.xz
(svn r10763) -Documentation [FS#1098]: document direction.h. Patch by Progman.
-rw-r--r--src/direction.h236
1 files changed, 195 insertions, 41 deletions
diff --git a/src/direction.h b/src/direction.h
index 837fa149f..84d6b952e 100644
--- a/src/direction.h
+++ b/src/direction.h
@@ -7,66 +7,128 @@
#include "helpers.hpp"
-/* Direction as commonly used in v->direction, 8 way. */
+/**
+ * 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,
- DIR_N = 0,
- DIR_NE = 1, ///< Northeast, upper right on your monitor
- DIR_E = 2,
- DIR_SE = 3,
- DIR_S = 4,
- DIR_SW = 5,
- DIR_W = 6,
- DIR_NW = 7,
- DIR_END,
- INVALID_DIR = 0xFF,
+ 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
+/**
+ * Return the reverse of a direction
+ *
+ * @param d The direction to get the reverse from
+ * @return The reverse Direction
+ */
static inline Direction ReverseDir(Direction d)
{
return (Direction)(4 ^ d);
}
+/**
+ * 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,
- DIRDIFF_45RIGHT = 1,
- DIRDIFF_90RIGHT = 2,
- DIRDIFF_REVERSE = 4,
- DIRDIFF_90LEFT = 6,
- DIRDIFF_45LEFT = 7
+ 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
};
+/**
+ * Calculate the difference between to directions
+ *
+ * @param d0 The first direction as the base
+ * @param d1 The second direction as the offset from the base
+ * @return The difference how the second directions drifts of the first one.
+ */
static inline DirDiff DirDifference(Direction d0, Direction d1)
{
return (DirDiff)((d0 + 8 - d1) % 8);
}
+/**
+ * Applies two differences together
+ *
+ * This function adds two differences together and return the resulting
+ * difference. So adding two DIRDIFF_REVERSE together results in the
+ * DIRDIFF_SAME difference.
+ *
+ * @param d The first difference
+ * @param delta The second difference to add on
+ * @return The resulting difference
+ */
static inline DirDiff ChangeDirDiff(DirDiff d, DirDiff delta)
{
return (DirDiff)((d + delta) % 8);
}
-
+/**
+ * Change a direction by a given difference
+ *
+ * This functions returns a new direction of the given direction
+ * which is rotated by the given difference.
+ *
+ * @param d The direction to get a new direction from
+ * @param delta The offset/drift applied to the direction
+ * @return The new direction
+ */
static inline Direction ChangeDir(Direction d, DirDiff delta)
{
return (Direction)((d + delta) % 8);
}
-/* Direction commonly used as the direction of entering and leaving tiles, 4-way */
+/**
+ * Enumeration for diagonal directions.
+ *
+ * This enumeration is used for the 4 direction of the tile-edges.
+ */
enum DiagDirection {
- DIAGDIR_BEGIN = 0,
- DIAGDIR_NE = 0, ///< Northeast, upper right on your monitor
- DIAGDIR_SE = 1,
- DIAGDIR_SW = 2,
- DIAGDIR_NW = 3,
- DIAGDIR_END,
- INVALID_DIAGDIR = 0xFF,
+ 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);
@@ -75,60 +137,135 @@ DECLARE_POSTFIX_INCREMENT(DiagDirection);
template <> struct EnumPropsT<DiagDirection> : MakeEnumPropsT<DiagDirection, byte, DIAGDIR_BEGIN, DIAGDIR_END, INVALID_DIAGDIR> {};
typedef TinyEnumT<DiagDirection> DiagDirectionByte; //typedefing-enumification of DiagDirection
+/**
+ * Returns the reverse direction of the given DiagDirection
+ *
+ * @param d The DiagDirection to get the reverse from
+ * @return The reverse direction
+ */
static inline DiagDirection ReverseDiagDir(DiagDirection d)
{
return (DiagDirection)(2 ^ d);
}
-
+/**
+ * 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,
- DIAGDIRDIFF_90RIGHT = 1,
- DIAGDIRDIFF_REVERSE = 2,
- DIAGDIRDIFF_90LEFT = 3
+ DIAGDIRDIFF_SAME = 0, ///< Same directions
+ DIAGDIRDIFF_90RIGHT = 1, ///< 90 degrees right
+ DIAGDIRDIFF_REVERSE = 2, ///< Reverse directions
+ DIAGDIRDIFF_90LEFT = 3 ///< 90 degrees left
};
+/**
+ * Applies a difference on a DiagDirection
+ *
+ * This function applies a difference on a DiagDirection and returns
+ * the new DiagDirection.
+ *
+ * @param d The DiagDirection
+ * @param delta The difference to applie on
+ * @return The new direction which was calculated
+ */
static inline DiagDirection ChangeDiagDir(DiagDirection d, DiagDirDiff delta)
{
return (DiagDirection)((d + delta) % 4);
}
-
+/**
+ * Convert a Direction to a DiagDirection.
+ *
+ * This function can be used to convert the 8-way Direction to
+ * the 4-way DiagDirection. If the direction cannot be mapped its
+ * "rounded clockwise". So DIR_N becomes DIAGDIR_NE.
+ *
+ * @param dir The direction to convert
+ * @return The resulting DiagDirection, maybe "rounded clockwise".
+ */
static inline DiagDirection DirToDiagDir(Direction dir)
{
return (DiagDirection)(dir >> 1);
}
-
+/**
+ * Convert a DiagDirection to a Direction.
+ *
+ * This function can be used to convert the 4-way DiagDirection
+ * to the 8-way Direction. As 4-way are less than 8-way not all
+ * possible directions can be calculated.
+ *
+ * @param dir The direction to convert
+ * @return The resulting Direction
+ */
static inline Direction DiagDirToDir(DiagDirection dir)
{
return (Direction)(dir * 2 + 1);
}
-/* the 2 axis */
+/**
+ * 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,
- AXIS_Y = 1,
- AXIS_END
+ AXIS_X = 0, ///< The X axis
+ AXIS_Y = 1, ///< The y axis
+ AXIS_END ///< Used for iterations
};
+/**
+ * Select the other axis as provided.
+ *
+ * This is basically the not-operator for the axis.
+ *
+ * @param a The given axis
+ * @return The other axis
+ */
static inline Axis OtherAxis(Axis a)
{
return (Axis)(a ^ 1);
}
+/**
+ * Convert a DiagDirection to the axis.
+ *
+ * This function returns the axis which belongs to the given
+ * DiagDirection. The axis X belongs to the DiagDirection
+ * north-east and south-west.
+ *
+ * @param d The DiagDirection
+ * @return The axis which belongs to the direction
+ */
static inline Axis DiagDirToAxis(DiagDirection d)
{
return (Axis)(d & 1);
}
-/*
+/**
* Converts an Axis to a DiagDirection
- * Points always in the positive direction, i.e. S[EW]
+ *
+ * This function returns the DiagDirection which
+ * belongs to the axis. As 2 directions are mapped to an axis
+ * this function returns the one which points to south,
+ * either south-west (on X axis) or south-east (on Y axis)
+ *
+ * @param a The axis
+ * @return The direction pointed to south
*/
static inline DiagDirection AxisToDiagDir(Axis a)
{
@@ -146,17 +283,34 @@ static inline DiagDirection XYNSToDiagDir(Axis xy, uint ns)
return (DiagDirection)(xy * 3 ^ ns * 2);
}
-
+/**
+ * Checks if an interger value is a valid DiagDirection
+ *
+ * @param d The value to check
+ * @return True if the value belongs to a DiagDirection, else false
+ */
static inline bool IsValidDiagDirection(DiagDirection d)
{
return d < DIAGDIR_END;
}
+/**
+ * Checks if an integer value is a valid Direction
+ *
+ * @param d The value to check
+ * @return True if the value belongs to a Direction, else false
+ */
static inline bool IsValidDirection(Direction d)
{
return d < DIR_END;
}
+/**
+ * Checks if an integer value is a valid Axis
+ *
+ * @param d The value to check
+ * @return True if the value belongs to an Axis, else false
+ */
static inline bool IsValidAxis(Axis d)
{
return d < AXIS_END;