File diff r22239:09a48e02b9bb → r22240:6d8570a35ab0
src/direction_func.h
Show inline comments
 
@@ -58,17 +58,17 @@ static inline Direction ReverseDir(Direc
 
	assert(IsValidDirection(d));
 
	return (Direction)(4 ^ d);
 
}
 

	
 

	
 
/**
 
 * Calculate the difference between to directions
 
 * Calculate the difference between two 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.
 
 * @return The difference how the second direction drifts of the first one.
 
 */
 
static inline DirDiff DirDifference(Direction d0, Direction d1)
 
{
 
	assert(IsValidDirection(d0));
 
	assert(IsValidDirection(d1));
 
	/* Cast to uint so compiler can use bitmask. If the difference is negative
 
@@ -76,13 +76,13 @@ static inline DirDiff DirDifference(Dire
 
	return (DirDiff)((uint)(d0 - d1) % 8);
 
}
 

	
 
/**
 
 * Applies two differences together
 
 *
 
 * This function adds two differences together and return the resulting
 
 * This function adds two differences together and returns 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
 
@@ -120,12 +120,26 @@ static inline Direction ChangeDir(Direct
 
static inline DiagDirection ReverseDiagDir(DiagDirection d)
 
{
 
	assert(IsValidDiagDirection(d));
 
	return (DiagDirection)(2 ^ d);
 
}
 

	
 
/**
 
 * Calculate the difference between two DiagDirection values
 
 *
 
 * @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 direction drifts of the first one.
 
 */
 
static inline DiagDirDiff DiagDirDifference(DiagDirection d0, DiagDirection d1)
 
{
 
	assert(IsValidDiagDirection(d0));
 
	assert(IsValidDiagDirection(d1));
 
	/* Cast to uint so compiler can use bitmask. Result can never be negative. */
 
	return (DiagDirDiff)((uint)(d0 - d1) % 4);
 
}
 

	
 
/**
 
 * Applies a difference on a DiagDirection
 
 *
 
 * This function applies a difference on a DiagDirection and returns
 
 * the new DiagDirection.