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Merge pull request #2446 from cuberite/asyncpathfinder

Fixed a position bug in the pathfinder
This commit is contained in:
Tiger Wang 2015-08-26 23:13:13 +01:00
commit 3b8dc45dc3
4 changed files with 25 additions and 101 deletions

View File

@ -76,8 +76,8 @@ cMonster::cMonster(const AString & a_ConfigName, eMonsterType a_MobType, const A
, m_Target(nullptr)
, m_Path(nullptr)
, m_IsFollowingPath(false)
, m_PathfinderActivated(false)
, m_GiveUpCounter(0)
, m_TicksSinceLastPathReset(1000)
, m_LastGroundHeight(POSY_TOINT)
, m_JumpCoolDown(0)
, m_IdleInterval(0)
@ -124,15 +124,10 @@ void cMonster::SpawnOn(cClientHandle & a_Client)
bool cMonster::TickPathFinding(cChunk & a_Chunk)
{
if (!m_IsFollowingPath)
if (!m_PathfinderActivated)
{
return false;
}
if (m_TicksSinceLastPathReset < 1000)
{
// No need to count beyond 1000. 1000 is arbitary here.
++m_TicksSinceLastPathReset;
}
if (ReachedFinalDestination())
{
@ -140,26 +135,6 @@ bool cMonster::TickPathFinding(cChunk & a_Chunk)
return false;
}
if ((m_FinalDestination - m_PathFinderDestination).Length() > 0.25) // if the distance between where we're going and where we should go is too big.
{
/* If we reached the last path waypoint,
Or if we haven't re-calculated for too long.
Interval is proportional to distance squared, and its minimum is 10.
(Recalculate lots when close, calculate rarely when far) */
if (
((GetPosition() - m_PathFinderDestination).Length() < 0.25) ||
((m_TicksSinceLastPathReset > 10) && (m_TicksSinceLastPathReset > (0.4 * (m_FinalDestination - GetPosition()).SqrLength())))
)
{
/* Re-calculating is expensive when there's no path to target, and it results in mobs freezing very often as a result of always recalculating.
This is a workaround till we get better path recalculation. */
if (!m_NoPathToTarget)
{
ResetPathFinding();
}
}
}
if (m_Path == nullptr)
{
if (!EnsureProperDestination(a_Chunk))
@ -167,21 +142,17 @@ bool cMonster::TickPathFinding(cChunk & a_Chunk)
StopMovingToPosition(); // Invalid chunks, probably world is loading or something, cancel movement.
return false;
}
m_NoPathToTarget = false;
m_NoMoreWayPoints = false;
m_PathFinderDestination = m_FinalDestination;
m_Path = new cPath(a_Chunk, GetPosition(), m_PathFinderDestination, 20, GetWidth(), GetHeight());
m_GiveUpCounter = 40;
m_Path = new cPath(a_Chunk, GetPosition(), m_FinalDestination, 20, GetWidth(), GetHeight());
}
switch (m_Path->Step(a_Chunk))
{
case ePathFinderStatus::NEARBY_FOUND:
{
m_NoPathToTarget = true;
m_PathFinderDestination = m_Path->AcceptNearbyPath();
m_FinalDestination = m_Path->AcceptNearbyPath();
break;
}
case ePathFinderStatus::PATH_NOT_FOUND:
{
StopMovingToPosition(); // Try to calculate a path again.
@ -195,9 +166,10 @@ bool cMonster::TickPathFinding(cChunk & a_Chunk)
}
case ePathFinderStatus::PATH_FOUND:
{
if (m_NoMoreWayPoints || (--m_GiveUpCounter == 0))
if ((--m_GiveUpCounter) == 0)
{
if (m_EMState == ATTACKING)
// Failed to reach a waypoint - that's a failure condition whichever point we're at
if (m_EMState == CHASING)
{
ResetPathFinding(); // Try to calculate a path again.
// This results in mobs hanging around an unreachable target (player).
@ -216,10 +188,8 @@ bool cMonster::TickPathFinding(cChunk & a_Chunk)
m_GiveUpCounter = 40; // Give up after 40 ticks (2 seconds) if failed to reach m_NextWayPointPosition.
}
}
else
{
m_NoMoreWayPoints = true;
}
m_IsFollowingPath = true;
return true;
}
}
@ -389,8 +359,8 @@ bool cMonster::EnsureProperDestination(cChunk & a_Chunk)
void cMonster::MoveToPosition(const Vector3d & a_Position)
{
m_FinalDestination = a_Position;
m_IsFollowingPath = true;
m_FinalDestination = a_Position;
m_PathfinderActivated = true;
}
@ -399,7 +369,7 @@ void cMonster::MoveToPosition(const Vector3d & a_Position)
void cMonster::StopMovingToPosition()
{
m_IsFollowingPath = false;
m_PathfinderActivated = false;
ResetPathFinding();
}
@ -409,7 +379,7 @@ void cMonster::StopMovingToPosition()
void cMonster::ResetPathFinding(void)
{
m_TicksSinceLastPathReset = 0;
m_IsFollowingPath = false;
if (m_Path != nullptr)
{
delete m_Path;

View File

@ -173,9 +173,11 @@ protected:
/** Stores if mobile is currently moving towards the ultimate, final destination */
bool m_IsFollowingPath;
/** Stores if pathfinder is being used - set when final destination is set, and unset when stopped moving to final destination */
bool m_PathfinderActivated;
/* If 0, will give up reaching the next m_NextWayPointPosition and will re-compute path. */
int m_GiveUpCounter;
int m_TicksSinceLastPathReset;
/** Coordinates of the next position that should be reached */
Vector3d m_NextWayPointPosition;
@ -183,16 +185,6 @@ protected:
/** Coordinates for the ultimate, final destination. */
Vector3d m_FinalDestination;
/** Coordinates for the ultimate, final destination last given to the pathfinder. */
Vector3d m_PathFinderDestination;
/** True if there's no path to target and we're walking to an approximated location. */
bool m_NoPathToTarget;
/** Whether The mob has finished their path, note that this does not imply reaching the destination,
the destination may sometimes differ from the current path. */
bool m_NoMoreWayPoints;
/** Finds the lowest non-air block position (not the highest, as cWorld::GetHeight does)
If current Y is nonsolid, goes down to try to find a solid block, then returns that + 1
If current Y is solid, goes up to find first nonsolid block, and returns that.

View File

@ -17,9 +17,6 @@
bool compareHeuristics::operator()(cPathCell * & a_Cell1, cPathCell * & a_Cell2)
{
return a_Cell1->m_F > a_Cell2->m_F;
@ -36,7 +33,7 @@ cPath::cPath(
double a_BoundingBoxWidth, double a_BoundingBoxHeight,
int a_MaxUp, int a_MaxDown
) :
m_StepsLeft(a_MaxSteps),
m_CurrentPoint(0), // GetNextPoint increments this to 1, but that's fine, since the first cell is always a_StartingPoint
m_Chunk(&a_Chunk),
m_BadChunkFound(false)
@ -67,22 +64,8 @@ cPath::cPath(
m_NearestPointToTarget = GetCell(m_Source);
m_Status = ePathFinderStatus::CALCULATING;
m_StepsLeft = a_MaxSteps;
ProcessCell(GetCell(a_StartingPoint), nullptr, 0);
m_Chunk = nullptr;
}
cPath::~cPath()
{
if (m_Status == ePathFinderStatus::CALCULATING)
{
FinishCalculation();
}
ProcessCell(GetCell(m_Source), nullptr, 0);
}
@ -113,7 +96,7 @@ ePathFinderStatus cPath::Step(cChunk & a_Chunk)
int i;
for (i = 0; i < CALCULATIONS_PER_STEP; ++i)
{
if (Step_Internal()) // Step_Internal returns true when no more calculation is needed.
if (StepOnce()) // StepOnce returns true when no more calculation is needed.
{
break; // if we're here, m_Status must have changed either to PATH_FOUND or PATH_NOT_FOUND.
}
@ -179,7 +162,7 @@ bool cPath::IsSolid(const Vector3i & a_Location)
bool cPath::Step_Internal()
bool cPath::StepOnce()
{
cPathCell * CurrentCell = OpenListPop();

View File

@ -72,10 +72,7 @@ public:
double a_BoundingBoxWidth, double a_BoundingBoxHeight,
int a_MaxUp = 1, int a_MaxDown = 1
);
/** Destroys the path and frees its memory. */
~cPath();
/** Performs part of the path calculation and returns the appropriate status.
If NEARBY_FOUND is returned, it means that the destination is not reachable, but a nearby destination
is reachable. If the user likes the alternative destination, they can call AcceptNearbyPath to treat the path as found,
@ -99,45 +96,27 @@ public:
/** Checks whether this is the last point or not. Never call getnextPoint when this is true. */
inline bool IsLastPoint()
inline bool IsLastPoint() const
{
ASSERT(m_Status == ePathFinderStatus::PATH_FOUND);
return (m_CurrentPoint == m_PathPoints.size() - 1);
}
inline bool IsFirstPoint()
inline bool IsFirstPoint() const
{
ASSERT(m_Status == ePathFinderStatus::PATH_FOUND);
return (m_CurrentPoint == 0);
}
/** Get the point at a_index. Remark: Internally, the indexes are reversed. */
inline Vector3d GetPoint(size_t a_index)
{
ASSERT(m_Status == ePathFinderStatus::PATH_FOUND);
ASSERT(a_index < m_PathPoints.size());
Vector3i Point = m_PathPoints[m_PathPoints.size() - 1 - a_index];
return Vector3d(Point.x + m_HalfWidth, Point.y, Point.z + m_HalfWidth);
}
/** Returns the total number of points this path has. */
inline size_t GetPointCount()
{
if (m_Status != ePathFinderStatus::PATH_FOUND)
{
return 0;
}
return m_PathPoints.size();
}
private:
/* General */
bool IsSolid(const Vector3i & a_Location); // Query our hosting world and ask it if there's a solid at a_location.
bool Step_Internal(); // The public version just calls this version * CALCULATIONS_PER_CALL times.
bool StepOnce(); // The public version just calls this version * CALCULATIONS_PER_CALL times.
void FinishCalculation(); // Clears the memory used for calculating the path.
void FinishCalculation(ePathFinderStatus a_NewStatus); // Clears the memory used for calculating the path and changes the status.
void AttemptToFindAlternative();