106 lines
1.9 KiB
C
106 lines
1.9 KiB
C
/* $Id$ */
|
|
|
|
#ifndef DIRECTION_H
|
|
#define DIRECTION_H
|
|
|
|
/* Direction as commonly used in v->direction, 8 way. */
|
|
typedef enum Direction {
|
|
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,
|
|
} Direction;
|
|
|
|
static inline Direction ReverseDir(Direction d)
|
|
{
|
|
return (Direction)(4 ^ d);
|
|
}
|
|
|
|
|
|
typedef enum DirDiff {
|
|
DIRDIFF_SAME = 0,
|
|
DIRDIFF_45RIGHT = 1,
|
|
DIRDIFF_90RIGHT = 2,
|
|
DIRDIFF_REVERSE = 4,
|
|
DIRDIFF_90LEFT = 6,
|
|
DIRDIFF_45LEFT = 7
|
|
} DirDiff;
|
|
|
|
static inline DirDiff DirDifference(Direction d0, Direction d1)
|
|
{
|
|
return (DirDiff)((d0 + 8 - d1) % 8);
|
|
}
|
|
|
|
static inline DirDiff ChangeDirDiff(DirDiff d, DirDiff delta)
|
|
{
|
|
return (DirDiff)((d + delta) % 8);
|
|
}
|
|
|
|
|
|
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 */
|
|
typedef enum DiagDirection {
|
|
DIAGDIR_NE = 0, /* Northeast, upper right on your monitor */
|
|
DIAGDIR_SE = 1,
|
|
DIAGDIR_SW = 2,
|
|
DIAGDIR_NW = 3,
|
|
DIAGDIR_END,
|
|
INVALID_DIAGDIR = 0xFF,
|
|
} DiagDirection;
|
|
|
|
static inline DiagDirection ReverseDiagDir(DiagDirection d)
|
|
{
|
|
return (DiagDirection)(2 ^ d);
|
|
}
|
|
|
|
|
|
typedef enum DiagDirDiff {
|
|
DIAGDIRDIFF_SAME = 0,
|
|
DIAGDIRDIFF_90RIGHT = 1,
|
|
DIAGDIRDIFF_REVERSE = 2,
|
|
DIAGDIRDIFF_90LEFT = 3
|
|
} DiagDirDiff;
|
|
|
|
static inline DiagDirection ChangeDiagDir(DiagDirection d, DiagDirDiff delta)
|
|
{
|
|
return (DiagDirection)((d + delta) % 4);
|
|
}
|
|
|
|
|
|
static inline DiagDirection DirToDiagDir(Direction dir)
|
|
{
|
|
return (DiagDirection)(dir >> 1);
|
|
}
|
|
|
|
|
|
static inline Direction DiagDirToDir(DiagDirection dir)
|
|
{
|
|
return (Direction)(dir * 2 + 1);
|
|
}
|
|
|
|
|
|
/* the 2 axis */
|
|
typedef enum Axis {
|
|
AXIS_X = 0,
|
|
AXIS_Y = 1
|
|
} Axis;
|
|
|
|
|
|
static inline Axis DiagDirToAxis(DiagDirection d)
|
|
{
|
|
return (Axis)(d & 1);
|
|
}
|
|
|
|
#endif
|