OpenTTD-patches/src/road_func.h

117 lines
2.6 KiB
C

/* $Id$ */
/** @file road_func.h Functions related to roads. */
#ifndef ROAD_FUNC_H
#define ROAD_FUNC_H
#include "core/bitmath_func.hpp"
#include "road_type.h"
#include "direction_func.h"
/**
* Whether the given roadtype is valid.
* @param rt the roadtype to check for validness
* @return true if and only if valid
*/
static inline bool IsValidRoadType(RoadType rt)
{
return rt == ROADTYPE_ROAD || rt == ROADTYPE_TRAM;
}
/**
* Are the given bits pointing to valid roadtypes?
* @param rts the roadtypes to check for validness
* @return true if and only if valid
*/
static inline bool AreValidRoadTypes(RoadTypes rts)
{
return HasBit(rts, ROADTYPE_ROAD) || HasBit(rts, ROADTYPE_TRAM);
}
/**
* Maps a RoadType to the corresponding RoadTypes value
*
* @param rt the roadtype to get the roadtypes from
* @return the roadtypes with the given roadtype
*/
static inline RoadTypes RoadTypeToRoadTypes(RoadType rt)
{
return (RoadTypes)(1 << rt);
}
/**
* Returns the RoadTypes which are not present in the given RoadTypes
*
* This function returns the complement of a given RoadTypes.
*
* @param r The given RoadTypes
* @return The complement of the given RoadTypes
* @note The unused value ROADTYPES_HWAY will be used, too.
*/
static inline RoadTypes ComplementRoadTypes(RoadTypes r)
{
return (RoadTypes)(ROADTYPES_ALL ^ r);
}
/**
* Calculate the complement of a RoadBits value
*
* Simply flips all bits in the RoadBits value to get the complement
* of the RoadBits.
*
* @param r The given RoadBits value
* @return the complement
*/
static inline RoadBits ComplementRoadBits(RoadBits r)
{
return (RoadBits)(ROAD_ALL ^ r);
}
/**
* Calculate the mirrored RoadBits
*
* Simply move the bits to their new position.
*
* @param r The given RoadBits value
* @return the mirrored
*/
static inline RoadBits MirrorRoadBits(RoadBits r)
{
return (RoadBits)(GB(r, 0, 2) << 2 | GB(r, 2, 2));
}
/**
* Calculate rotated RoadBits
*
* Move the Roadbits clockwise til they are in their final position.
*
* @param r The given RoadBits value
* @param rot The given Rotation angle
* @return the rotated
*/
static inline RoadBits RotateRoadBits(RoadBits r, DiagDirDiff rot)
{
for (; rot > (DiagDirDiff)0; rot--){
r = (RoadBits)(GB(r, 0, 1) << 3 | GB(r, 1, 3));
}
return r;
}
/**
* Create the road-part which belongs to the given DiagDirection
*
* This function returns a RoadBits value which belongs to
* the given DiagDirection.
*
* @param d The DiagDirection
* @return The result RoadBits which the selected road-part set
*/
static inline RoadBits DiagDirToRoadBits(DiagDirection d)
{
return (RoadBits)(ROAD_NW << (3 ^ d));
}
#endif /* ROAD_FUNC_H */