mirror of
https://github.com/minetest/minetest.git
synced 2024-08-18 20:44:16 +02:00
Fix pathfinder bugs: returning nil frequently, broken A*, jump through solid nodes (#9339)
* Fix pathfinder fail when startpos is over air * Note down pathfinder restrictions * Implement real A* search * Pathfinder: Implement buildPath non-recursively * Update find_path documentation * Pathfinder: Check if jump path is unobstructed * Pathfinder: Fix drop check first checking upwards * Pathfinder: Return nil if source or dest are solid * Pathfinder: Use priority queue for open list
This commit is contained in:
parent
6d8e2d2483
commit
580e7e8eb9
@ -15,6 +15,7 @@ core.features = {
|
||||
httpfetch_binary_data = true,
|
||||
formspec_version_element = true,
|
||||
area_store_persistent_ids = true,
|
||||
pathfinder_works = true,
|
||||
}
|
||||
|
||||
function core.has_feature(arg)
|
||||
|
@ -4045,6 +4045,8 @@ Utilities
|
||||
formspec_version_element = true,
|
||||
-- Whether AreaStore's IDs are kept on save/load (5.1.0)
|
||||
area_store_persistent_ids = true,
|
||||
-- Whether minetest.find_path is functional (5.2.0)
|
||||
pathfinder_works = true,
|
||||
}
|
||||
|
||||
* `minetest.has_feature(arg)`: returns `boolean, missing_features`
|
||||
@ -4709,16 +4711,25 @@ Environment access
|
||||
* `objects`: if false, only nodes will be returned. Default is `true`.
|
||||
* `liquids`: if false, liquid nodes won't be returned. Default is `false`.
|
||||
* `minetest.find_path(pos1,pos2,searchdistance,max_jump,max_drop,algorithm)`
|
||||
* returns table containing path
|
||||
* returns table containing path that can be walked on
|
||||
* returns a table of 3D points representing a path from `pos1` to `pos2` or
|
||||
`nil`.
|
||||
`nil` on failure.
|
||||
* Reasons for failure:
|
||||
* No path exists at all
|
||||
* No path exists within `searchdistance` (see below)
|
||||
* Start or end pos is buried in land
|
||||
* `pos1`: start position
|
||||
* `pos2`: end position
|
||||
* `searchdistance`: number of blocks to search in each direction using a
|
||||
maximum metric.
|
||||
* `searchdistance`: maximum distance from the search positions to search in.
|
||||
In detail: Path must be completely inside a cuboid. The minimum
|
||||
`searchdistance` of 1 will confine search between `pos1` and `pos2`.
|
||||
Larger values will increase the size of this cuboid in all directions
|
||||
* `max_jump`: maximum height difference to consider walkable
|
||||
* `max_drop`: maximum height difference to consider droppable
|
||||
* `algorithm`: One of `"A*_noprefetch"` (default), `"A*"`, `"Dijkstra"`
|
||||
* `algorithm`: One of `"A*_noprefetch"` (default), `"A*"`, `"Dijkstra"`.
|
||||
Difference between `"A*"` and `"A*_noprefetch"` is that
|
||||
`"A*"` will pre-calculate the cost-data, the other will calculate it
|
||||
on-the-fly
|
||||
* `minetest.spawn_tree (pos, {treedef})`
|
||||
* spawns L-system tree at given `pos` with definition in `treedef` table
|
||||
* `minetest.transforming_liquid_add(pos)`
|
||||
|
@ -58,6 +58,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
|
||||
#define ERROR_TARGET warningstream << "Pathfinder: "
|
||||
#endif
|
||||
|
||||
#define PATHFINDER_MAX_WAYPOINTS 700
|
||||
|
||||
/******************************************************************************/
|
||||
/* Class definitions */
|
||||
/******************************************************************************/
|
||||
@ -78,7 +80,7 @@ public:
|
||||
|
||||
bool valid = false; /**< movement is possible */
|
||||
int value = 0; /**< cost of movement */
|
||||
int direction = 0; /**< y-direction of movement */
|
||||
int y_change = 0; /**< change of y position of movement */
|
||||
bool updated = false; /**< this cost has ben calculated */
|
||||
|
||||
};
|
||||
@ -117,16 +119,26 @@ public:
|
||||
bool target = false; /**< node is target position */
|
||||
bool source = false; /**< node is stating position */
|
||||
int totalcost = -1; /**< cost to move here from starting point */
|
||||
int estimated_cost = -1; /**< totalcost + heuristic cost to end */
|
||||
v3s16 sourcedir; /**< origin of movement for current cost */
|
||||
v3s16 pos; /**< real position of node */
|
||||
PathCost directions[4]; /**< cost in different directions */
|
||||
bool is_closed = false; /**< for A* search: if true, is in closed list */
|
||||
bool is_open = false; /**< for A* search: if true, is in open list */
|
||||
|
||||
/* debug values */
|
||||
bool is_element = false; /**< node is element of path detected */
|
||||
char type = 'u'; /**< type of node */
|
||||
char type = 'u'; /**< Type of pathfinding node.
|
||||
* u = unknown
|
||||
* i = invalid
|
||||
* s = surface (walkable node)
|
||||
* - = non-walkable node (e.g. air) above surface
|
||||
* g = other non-walkable node
|
||||
*/
|
||||
};
|
||||
|
||||
class Pathfinder;
|
||||
class PathfinderCompareHeuristic;
|
||||
|
||||
/** Abstract class to manage the map data */
|
||||
class GridNodeContainer {
|
||||
@ -224,8 +236,8 @@ private:
|
||||
PathGridnode &getIdxElem(s16 x, s16 y, s16 z);
|
||||
|
||||
/**
|
||||
* invert a 3d position
|
||||
* @param pos 3d position
|
||||
* invert a 3D position (change sign of coordinates)
|
||||
* @param pos 3D position
|
||||
* @return pos *-1
|
||||
*/
|
||||
v3s16 invert(v3s16 pos);
|
||||
@ -237,37 +249,16 @@ private:
|
||||
*/
|
||||
bool isValidIndex(v3s16 index);
|
||||
|
||||
/**
|
||||
* translate position to float position
|
||||
* @param pos integer position
|
||||
* @return float position
|
||||
*/
|
||||
v3f tov3f(v3s16 pos);
|
||||
|
||||
|
||||
/* algorithm functions */
|
||||
|
||||
/**
|
||||
* calculate 2d manahttan distance to target on the xz plane
|
||||
* calculate 2D Manhattan distance to target
|
||||
* @param pos position to calc distance
|
||||
* @return integer distance
|
||||
*/
|
||||
int getXZManhattanDist(v3s16 pos);
|
||||
|
||||
/**
|
||||
* get best direction based uppon heuristics
|
||||
* @param directions list of unchecked directions
|
||||
* @param g_pos mapnode to start from
|
||||
* @return direction to check
|
||||
*/
|
||||
v3s16 getDirHeuristic(std::vector<v3s16> &directions, PathGridnode &g_pos);
|
||||
|
||||
/**
|
||||
* build internal data representation of search area
|
||||
* @return true/false if costmap creation was successfull
|
||||
*/
|
||||
bool buildCostmap();
|
||||
|
||||
/**
|
||||
* calculate cost of movement
|
||||
* @param pos real world position to start movement
|
||||
@ -287,22 +278,32 @@ private:
|
||||
bool updateAllCosts(v3s16 ipos, v3s16 srcdir, int current_cost, int level);
|
||||
|
||||
/**
|
||||
* recursive try to find a patrh to destionation
|
||||
* @param ipos position to check next
|
||||
* @param srcdir positionc checked last time
|
||||
* @param total_cost cost of moving to ipos
|
||||
* @param level current recursion depth
|
||||
* try to find a path to destination using a heuristic function
|
||||
* to estimate distance to target (A* search algorithm)
|
||||
* @param isource start position (index pos)
|
||||
* @param idestination end position (index pos)
|
||||
* @return true/false path to destination has been found
|
||||
*/
|
||||
bool updateCostHeuristic(v3s16 ipos, v3s16 srcdir, int current_cost, int level);
|
||||
bool updateCostHeuristic(v3s16 isource, v3s16 idestination);
|
||||
|
||||
/**
|
||||
* recursive build a vector containing all nodes from source to destination
|
||||
* build a vector containing all nodes from destination to source;
|
||||
* to be called after the node costs have been processed
|
||||
* @param path vector to add nodes to
|
||||
* @param pos pos to check next
|
||||
* @param level recursion depth
|
||||
* @param ipos initial pos to check (index pos)
|
||||
* @return true/false path has been fully built
|
||||
*/
|
||||
void buildPath(std::vector<v3s16> &path, v3s16 pos, int level);
|
||||
bool buildPath(std::vector<v3s16> &path, v3s16 ipos);
|
||||
|
||||
/**
|
||||
* go downwards from a position until some barrier
|
||||
* is hit.
|
||||
* @param pos position from which to go downwards
|
||||
* @param max_down maximum distance to go downwards
|
||||
* @return new position after movement; if too far down,
|
||||
* pos is returned
|
||||
*/
|
||||
v3s16 walkDownwards(v3s16 pos, unsigned int max_down);
|
||||
|
||||
/* variables */
|
||||
int m_max_index_x = 0; /**< max index of search area in x direction */
|
||||
@ -329,6 +330,8 @@ private:
|
||||
|
||||
ServerEnvironment *m_env = 0; /**< minetest environment pointer */
|
||||
|
||||
friend class PathfinderCompareHeuristic;
|
||||
|
||||
#ifdef PATHFINDER_DEBUG
|
||||
|
||||
/**
|
||||
@ -378,6 +381,31 @@ private:
|
||||
#endif
|
||||
};
|
||||
|
||||
/** Helper class for the open list priority queue in the A* pathfinder
|
||||
* to sort the pathfinder nodes by cost.
|
||||
*/
|
||||
class PathfinderCompareHeuristic
|
||||
{
|
||||
private:
|
||||
Pathfinder *myPathfinder;
|
||||
public:
|
||||
PathfinderCompareHeuristic(Pathfinder *pf)
|
||||
{
|
||||
myPathfinder = pf;
|
||||
}
|
||||
bool operator() (v3s16 pos1, v3s16 pos2) {
|
||||
v3s16 ipos1 = myPathfinder->getIndexPos(pos1);
|
||||
v3s16 ipos2 = myPathfinder->getIndexPos(pos2);
|
||||
PathGridnode &g_pos1 = myPathfinder->getIndexElement(ipos1);
|
||||
PathGridnode &g_pos2 = myPathfinder->getIndexElement(ipos2);
|
||||
if (!g_pos1.valid)
|
||||
return false;
|
||||
if (!g_pos2.valid)
|
||||
return false;
|
||||
return g_pos1.estimated_cost > g_pos2.estimated_cost;
|
||||
}
|
||||
};
|
||||
|
||||
/******************************************************************************/
|
||||
/* implementation */
|
||||
/******************************************************************************/
|
||||
@ -401,7 +429,7 @@ std::vector<v3s16> get_path(ServerEnvironment* env,
|
||||
PathCost::PathCost(const PathCost &b)
|
||||
{
|
||||
valid = b.valid;
|
||||
direction = b.direction;
|
||||
y_change = b.y_change;
|
||||
value = b.value;
|
||||
updated = b.updated;
|
||||
}
|
||||
@ -410,7 +438,7 @@ PathCost::PathCost(const PathCost &b)
|
||||
PathCost &PathCost::operator= (const PathCost &b)
|
||||
{
|
||||
valid = b.valid;
|
||||
direction = b.direction;
|
||||
y_change = b.y_change;
|
||||
value = b.value;
|
||||
updated = b.updated;
|
||||
|
||||
@ -598,10 +626,11 @@ std::vector<v3s16> Pathfinder::getPath(ServerEnvironment *env,
|
||||
|
||||
//check parameters
|
||||
if (env == 0) {
|
||||
ERROR_TARGET << "missing environment pointer" << std::endl;
|
||||
ERROR_TARGET << "Missing environment pointer" << std::endl;
|
||||
return retval;
|
||||
}
|
||||
|
||||
//initialization
|
||||
m_searchdistance = searchdistance;
|
||||
m_env = env;
|
||||
m_maxjump = max_jump;
|
||||
@ -615,6 +644,7 @@ std::vector<v3s16> Pathfinder::getPath(ServerEnvironment *env,
|
||||
m_prefetch = false;
|
||||
}
|
||||
|
||||
//calculate boundaries within we're allowed to search
|
||||
int min_x = MYMIN(source.X, destination.X);
|
||||
int max_x = MYMAX(source.X, destination.X);
|
||||
|
||||
@ -650,7 +680,37 @@ std::vector<v3s16> Pathfinder::getPath(ServerEnvironment *env,
|
||||
printYdir();
|
||||
#endif
|
||||
|
||||
//fail if source or destination is walkable
|
||||
const NodeDefManager *ndef = m_env->getGameDef()->ndef();
|
||||
MapNode node_at_pos = m_env->getMap().getNode(destination);
|
||||
if (ndef->get(node_at_pos).walkable) {
|
||||
VERBOSE_TARGET << "Destination is walkable. " <<
|
||||
"Pos: " << PP(destination) << std::endl;
|
||||
return retval;
|
||||
}
|
||||
node_at_pos = m_env->getMap().getNode(source);
|
||||
if (ndef->get(node_at_pos).walkable) {
|
||||
VERBOSE_TARGET << "Source is walkable. " <<
|
||||
"Pos: " << PP(source) << std::endl;
|
||||
return retval;
|
||||
}
|
||||
|
||||
//If source pos is hovering above air, drop
|
||||
//to the first walkable node (up to m_maxdrop).
|
||||
//All algorithms expect the source pos to be *directly* above
|
||||
//a walkable node.
|
||||
v3s16 true_source = v3s16(source);
|
||||
source = walkDownwards(source, m_maxdrop);
|
||||
|
||||
//If destination pos is hovering above air, go downwards
|
||||
//to the first walkable node (up to m_maxjump).
|
||||
//This means a hovering destination pos could be reached
|
||||
//by a final upwards jump.
|
||||
v3s16 true_destination = v3s16(destination);
|
||||
destination = walkDownwards(destination, m_maxjump);
|
||||
|
||||
//validate and mark start and end pos
|
||||
|
||||
v3s16 StartIndex = getIndexPos(source);
|
||||
v3s16 EndIndex = getIndexPos(destination);
|
||||
|
||||
@ -658,13 +718,13 @@ std::vector<v3s16> Pathfinder::getPath(ServerEnvironment *env,
|
||||
PathGridnode &endpos = getIndexElement(EndIndex);
|
||||
|
||||
if (!startpos.valid) {
|
||||
VERBOSE_TARGET << "invalid startpos" <<
|
||||
VERBOSE_TARGET << "Invalid startpos " <<
|
||||
"Index: " << PP(StartIndex) <<
|
||||
"Realpos: " << PP(getRealPos(StartIndex)) << std::endl;
|
||||
return retval;
|
||||
}
|
||||
if (!endpos.valid) {
|
||||
VERBOSE_TARGET << "invalid stoppos" <<
|
||||
VERBOSE_TARGET << "Invalid stoppos " <<
|
||||
"Index: " << PP(EndIndex) <<
|
||||
"Realpos: " << PP(getRealPos(EndIndex)) << std::endl;
|
||||
return retval;
|
||||
@ -676,16 +736,17 @@ std::vector<v3s16> Pathfinder::getPath(ServerEnvironment *env,
|
||||
|
||||
bool update_cost_retval = false;
|
||||
|
||||
//calculate node costs
|
||||
switch (algo) {
|
||||
case PA_DIJKSTRA:
|
||||
update_cost_retval = updateAllCosts(StartIndex, v3s16(0, 0, 0), 0, 0);
|
||||
break;
|
||||
case PA_PLAIN_NP:
|
||||
case PA_PLAIN:
|
||||
update_cost_retval = updateCostHeuristic(StartIndex, v3s16(0, 0, 0), 0, 0);
|
||||
update_cost_retval = updateCostHeuristic(StartIndex, EndIndex);
|
||||
break;
|
||||
default:
|
||||
ERROR_TARGET << "missing PathAlgorithm"<< std::endl;
|
||||
ERROR_TARGET << "Missing PathAlgorithm" << std::endl;
|
||||
break;
|
||||
}
|
||||
|
||||
@ -697,23 +758,50 @@ std::vector<v3s16> Pathfinder::getPath(ServerEnvironment *env,
|
||||
#endif
|
||||
|
||||
//find path
|
||||
std::vector<v3s16> path;
|
||||
buildPath(path, EndIndex, 0);
|
||||
std::vector<v3s16> index_path;
|
||||
buildPath(index_path, EndIndex);
|
||||
//Now we have a path of index positions,
|
||||
//and it's in reverse.
|
||||
//The "true" start or end position might be missing
|
||||
//since those have been given special treatment.
|
||||
|
||||
#ifdef PATHFINDER_DEBUG
|
||||
std::cout << "Full index path:" << std::endl;
|
||||
printPath(path);
|
||||
std::cout << "Index path:" << std::endl;
|
||||
printPath(index_path);
|
||||
#endif
|
||||
|
||||
//finalize path
|
||||
//from here we'll make the final changes to the path
|
||||
std::vector<v3s16> full_path;
|
||||
full_path.reserve(path.size());
|
||||
for (const v3s16 &i : path) {
|
||||
full_path.push_back(getIndexElement(i).pos);
|
||||
|
||||
//calculate required size
|
||||
int full_path_size = index_path.size();
|
||||
if (source != true_source) {
|
||||
full_path_size++;
|
||||
}
|
||||
if (destination != true_destination) {
|
||||
full_path_size++;
|
||||
}
|
||||
full_path.reserve(full_path_size);
|
||||
|
||||
//manually add true_source to start of path, if needed
|
||||
if (source != true_source) {
|
||||
full_path.push_back(true_source);
|
||||
}
|
||||
//convert all index positions to "normal" positions and insert
|
||||
//them into full_path in reverse
|
||||
std::vector<v3s16>::reverse_iterator rit = index_path.rbegin();
|
||||
for (; rit != index_path.rend(); ++rit) {
|
||||
full_path.push_back(getIndexElement(*rit).pos);
|
||||
}
|
||||
//manually add true_destination to end of path, if needed
|
||||
if (destination != true_destination) {
|
||||
full_path.push_back(true_destination);
|
||||
}
|
||||
|
||||
//Done! We now have a complete path of normal positions.
|
||||
|
||||
|
||||
#ifdef PATHFINDER_DEBUG
|
||||
std::cout << "full path:" << std::endl;
|
||||
std::cout << "Full path:" << std::endl;
|
||||
printPath(full_path);
|
||||
#endif
|
||||
#ifdef PATHFINDER_CALC_TIME
|
||||
@ -734,7 +822,7 @@ std::vector<v3s16> Pathfinder::getPath(ServerEnvironment *env,
|
||||
#ifdef PATHFINDER_DEBUG
|
||||
printPathLen();
|
||||
#endif
|
||||
ERROR_TARGET << "failed to update cost map"<< std::endl;
|
||||
INFO_TARGET << "No path found" << std::endl;
|
||||
}
|
||||
|
||||
|
||||
@ -789,15 +877,18 @@ PathCost Pathfinder::calcCost(v3s16 pos, v3s16 dir)
|
||||
return retval;
|
||||
}
|
||||
|
||||
//test if the same-height neighbor is suitable
|
||||
if (ndef->get(node_below_pos2).walkable) {
|
||||
//SUCCESS!
|
||||
retval.valid = true;
|
||||
retval.value = 1;
|
||||
retval.direction = 0;
|
||||
retval.y_change = 0;
|
||||
DEBUG_OUT("Pathfinder: "<< PP(pos)
|
||||
<< " cost same height found" << std::endl);
|
||||
}
|
||||
else {
|
||||
v3s16 testpos = pos2 - v3s16(0, -1, 0);
|
||||
//test if we can fall a couple of nodes (m_maxdrop)
|
||||
v3s16 testpos = pos2 + v3s16(0, -1, 0);
|
||||
MapNode node_at_pos = m_env->getMap().getNode(testpos);
|
||||
|
||||
while ((node_at_pos.param0 != CONTENT_IGNORE) &&
|
||||
@ -812,15 +903,16 @@ PathCost Pathfinder::calcCost(v3s16 pos, v3s16 dir)
|
||||
(node_at_pos.param0 != CONTENT_IGNORE) &&
|
||||
(ndef->get(node_at_pos).walkable)) {
|
||||
if ((pos2.Y - testpos.Y - 1) <= m_maxdrop) {
|
||||
//SUCCESS!
|
||||
retval.valid = true;
|
||||
retval.value = 2;
|
||||
//difference of y-pos +1 (target node is ABOVE solid node)
|
||||
retval.direction = ((testpos.Y - pos2.Y) +1);
|
||||
retval.y_change = ((testpos.Y - pos2.Y) +1);
|
||||
DEBUG_OUT("Pathfinder cost below height found" << std::endl);
|
||||
}
|
||||
else {
|
||||
INFO_TARGET << "Pathfinder:"
|
||||
" distance to surface below to big: "
|
||||
" distance to surface below too big: "
|
||||
<< (testpos.Y - pos2.Y) << " max: " << m_maxdrop
|
||||
<< std::endl;
|
||||
}
|
||||
@ -831,29 +923,49 @@ PathCost Pathfinder::calcCost(v3s16 pos, v3s16 dir)
|
||||
}
|
||||
}
|
||||
else {
|
||||
v3s16 testpos = pos2;
|
||||
MapNode node_at_pos = m_env->getMap().getNode(testpos);
|
||||
//test if we can jump upwards (m_maxjump)
|
||||
|
||||
while ((node_at_pos.param0 != CONTENT_IGNORE) &&
|
||||
(ndef->get(node_at_pos).walkable) &&
|
||||
(testpos.Y < m_limits.MaxEdge.Y)) {
|
||||
testpos += v3s16(0, 1, 0);
|
||||
node_at_pos = m_env->getMap().getNode(testpos);
|
||||
v3s16 targetpos = pos2; // position for jump target
|
||||
v3s16 jumppos = pos; // position for checking if jumping space is free
|
||||
MapNode node_target = m_env->getMap().getNode(targetpos);
|
||||
MapNode node_jump = m_env->getMap().getNode(jumppos);
|
||||
bool headbanger = false; // true if anything blocks jumppath
|
||||
|
||||
while ((node_target.param0 != CONTENT_IGNORE) &&
|
||||
(ndef->get(node_target).walkable) &&
|
||||
(targetpos.Y < m_limits.MaxEdge.Y)) {
|
||||
//if the jump would hit any solid node, discard
|
||||
if ((node_jump.param0 == CONTENT_IGNORE) ||
|
||||
(ndef->get(node_jump).walkable)) {
|
||||
headbanger = true;
|
||||
break;
|
||||
}
|
||||
targetpos += v3s16(0, 1, 0);
|
||||
jumppos += v3s16(0, 1, 0);
|
||||
node_target = m_env->getMap().getNode(targetpos);
|
||||
node_jump = m_env->getMap().getNode(jumppos);
|
||||
|
||||
}
|
||||
//check headbanger one last time
|
||||
if ((node_jump.param0 == CONTENT_IGNORE) ||
|
||||
(ndef->get(node_jump).walkable)) {
|
||||
headbanger = true;
|
||||
}
|
||||
|
||||
//did we find surface?
|
||||
if ((testpos.Y <= m_limits.MaxEdge.Y) &&
|
||||
(!ndef->get(node_at_pos).walkable)) {
|
||||
//did we find surface without banging our head?
|
||||
if ((!headbanger) && (targetpos.Y <= m_limits.MaxEdge.Y) &&
|
||||
(!ndef->get(node_target).walkable)) {
|
||||
|
||||
if (testpos.Y - pos2.Y <= m_maxjump) {
|
||||
if (targetpos.Y - pos2.Y <= m_maxjump) {
|
||||
//SUCCESS!
|
||||
retval.valid = true;
|
||||
retval.value = 2;
|
||||
retval.direction = (testpos.Y - pos2.Y);
|
||||
retval.y_change = (targetpos.Y - pos2.Y);
|
||||
DEBUG_OUT("Pathfinder cost above found" << std::endl);
|
||||
}
|
||||
else {
|
||||
DEBUG_OUT("Pathfinder: distance to surface above to big: "
|
||||
<< (testpos.Y - pos2.Y) << " max: " << m_maxjump
|
||||
DEBUG_OUT("Pathfinder: distance to surface above too big: "
|
||||
<< (targetpos.Y - pos2.Y) << " max: " << m_maxjump
|
||||
<< std::endl);
|
||||
}
|
||||
}
|
||||
@ -929,19 +1041,20 @@ bool Pathfinder::updateAllCosts(v3s16 ipos,
|
||||
|
||||
bool retval = false;
|
||||
|
||||
std::vector<v3s16> directions;
|
||||
// the 4 cardinal directions
|
||||
const static v3s16 directions[4] = {
|
||||
v3s16(1,0, 0),
|
||||
v3s16(-1,0, 0),
|
||||
v3s16(0,0, 1),
|
||||
v3s16(0,0,-1)
|
||||
};
|
||||
|
||||
directions.emplace_back(1,0, 0);
|
||||
directions.emplace_back(-1,0, 0);
|
||||
directions.emplace_back(0,0, 1);
|
||||
directions.emplace_back(0,0,-1);
|
||||
|
||||
for (v3s16 &direction : directions) {
|
||||
for (v3s16 direction : directions) {
|
||||
if (direction != srcdir) {
|
||||
PathCost cost = g_pos.getCost(direction);
|
||||
|
||||
if (cost.valid) {
|
||||
direction.Y = cost.direction;
|
||||
direction.Y = cost.y_change;
|
||||
|
||||
v3s16 ipos2 = ipos + direction;
|
||||
|
||||
@ -1006,194 +1119,172 @@ int Pathfinder::getXZManhattanDist(v3s16 pos)
|
||||
return (max_x - min_x) + (max_z - min_z);
|
||||
}
|
||||
|
||||
|
||||
|
||||
/******************************************************************************/
|
||||
v3s16 Pathfinder::getDirHeuristic(std::vector<v3s16> &directions, PathGridnode &g_pos)
|
||||
bool Pathfinder::updateCostHeuristic(v3s16 isource, v3s16 idestination)
|
||||
{
|
||||
int minscore = -1;
|
||||
v3s16 retdir = v3s16(0, 0, 0);
|
||||
v3s16 srcpos = g_pos.pos;
|
||||
DEBUG_OUT("Pathfinder: remaining dirs at beginning:"
|
||||
<< directions.size() << std::endl);
|
||||
// A* search algorithm.
|
||||
|
||||
for (v3s16 &direction : directions) {
|
||||
// The open list contains the pathfinder nodes that still need to be
|
||||
// checked. The priority queue sorts the pathfinder nodes by
|
||||
// estimated cost, with lowest cost on the top.
|
||||
std::priority_queue<v3s16, std::vector<v3s16>, PathfinderCompareHeuristic>
|
||||
openList(PathfinderCompareHeuristic(this));
|
||||
|
||||
v3s16 pos1 = v3s16(srcpos.X + direction.X, 0, srcpos.Z+ direction.Z);
|
||||
v3s16 source = getRealPos(isource);
|
||||
v3s16 destination = getRealPos(idestination);
|
||||
|
||||
int cur_manhattan = getXZManhattanDist(pos1);
|
||||
PathCost cost = g_pos.getCost(direction);
|
||||
// initial position
|
||||
openList.push(source);
|
||||
|
||||
if (!cost.updated) {
|
||||
cost = calcCost(g_pos.pos, direction);
|
||||
g_pos.setCost(direction, cost);
|
||||
// the 4 cardinal directions
|
||||
const static v3s16 directions[4] = {
|
||||
v3s16(1,0, 0),
|
||||
v3s16(-1,0, 0),
|
||||
v3s16(0,0, 1),
|
||||
v3s16(0,0,-1)
|
||||
};
|
||||
|
||||
v3s16 current_pos;
|
||||
PathGridnode& s_pos = getIndexElement(isource);
|
||||
s_pos.source = true;
|
||||
s_pos.totalcost = 0;
|
||||
|
||||
// estimated cost from start to finish
|
||||
int cur_manhattan = getXZManhattanDist(destination);
|
||||
s_pos.estimated_cost = cur_manhattan;
|
||||
|
||||
while (!openList.empty()) {
|
||||
// Pick node with lowest total cost estimate.
|
||||
// The "cheapest" node is always on top.
|
||||
current_pos = openList.top();
|
||||
openList.pop();
|
||||
v3s16 ipos = getIndexPos(current_pos);
|
||||
|
||||
// check if node is inside searchdistance and valid
|
||||
if (!isValidIndex(ipos)) {
|
||||
DEBUG_OUT(LVL " Pathfinder: " << PP(current_pos) <<
|
||||
" out of search distance, max=" << PP(m_limits.MaxEdge) << std::endl);
|
||||
continue;
|
||||
}
|
||||
|
||||
if (cost.valid) {
|
||||
int score = cost.value + cur_manhattan;
|
||||
PathGridnode& g_pos = getIndexElement(ipos);
|
||||
g_pos.is_closed = true;
|
||||
g_pos.is_open = false;
|
||||
if (!g_pos.valid) {
|
||||
continue;
|
||||
}
|
||||
|
||||
if ((minscore < 0)|| (score < minscore)) {
|
||||
minscore = score;
|
||||
retdir = direction;
|
||||
if (current_pos == destination) {
|
||||
// destination found, terminate
|
||||
g_pos.target = true;
|
||||
return true;
|
||||
}
|
||||
|
||||
// for this node, check the 4 cardinal directions
|
||||
for (v3s16 direction_flat : directions) {
|
||||
int current_totalcost = g_pos.totalcost;
|
||||
|
||||
// get cost from current node to currently checked direction
|
||||
PathCost cost = g_pos.getCost(direction_flat);
|
||||
if (!cost.updated) {
|
||||
cost = calcCost(current_pos, direction_flat);
|
||||
g_pos.setCost(direction_flat, cost);
|
||||
}
|
||||
// update Y component of direction if neighbor requires jump or fall
|
||||
v3s16 direction_3d = v3s16(direction_flat);
|
||||
direction_3d.Y = cost.y_change;
|
||||
|
||||
// get position of true neighbor
|
||||
v3s16 neighbor = current_pos + direction_3d;
|
||||
v3s16 ineighbor = getIndexPos(neighbor);
|
||||
PathGridnode &n_pos = getIndexElement(ineighbor);
|
||||
|
||||
if (cost.valid && !n_pos.is_closed && !n_pos.is_open) {
|
||||
// heuristic function; estimate cost from neighbor to destination
|
||||
cur_manhattan = getXZManhattanDist(neighbor);
|
||||
|
||||
// add neighbor to open list
|
||||
n_pos.sourcedir = invert(direction_3d);
|
||||
n_pos.totalcost = current_totalcost + cost.value;
|
||||
n_pos.estimated_cost = current_totalcost + cost.value + cur_manhattan;
|
||||
n_pos.is_open = true;
|
||||
openList.push(neighbor);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (retdir != v3s16(0, 0, 0)) {
|
||||
for (std::vector<v3s16>::iterator iter = directions.begin();
|
||||
iter != directions.end();
|
||||
++iter) {
|
||||
if(*iter == retdir) {
|
||||
DEBUG_OUT("Pathfinder: removing return direction" << std::endl);
|
||||
directions.erase(iter);
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
else {
|
||||
DEBUG_OUT("Pathfinder: didn't find any valid direction clearing"
|
||||
<< std::endl);
|
||||
directions.clear();
|
||||
}
|
||||
DEBUG_OUT("Pathfinder: remaining dirs at end:" << directions.size()
|
||||
<< std::endl);
|
||||
return retdir;
|
||||
// no path found; all possible nodes within searchdistance have been exhausted
|
||||
return false;
|
||||
}
|
||||
|
||||
/******************************************************************************/
|
||||
bool Pathfinder::updateCostHeuristic( v3s16 ipos,
|
||||
v3s16 srcdir,
|
||||
int current_cost,
|
||||
int level)
|
||||
bool Pathfinder::buildPath(std::vector<v3s16> &path, v3s16 ipos)
|
||||
{
|
||||
// The cost calculation should have set a source direction for all relevant nodes.
|
||||
// To build the path, we go backwards from the destination until we reach the start.
|
||||
for(u32 waypoints = 1; waypoints++; ) {
|
||||
if (waypoints > PATHFINDER_MAX_WAYPOINTS) {
|
||||
ERROR_TARGET << "Pathfinder: buildPath: path is too long (too many waypoints), aborting" << std::endl;
|
||||
return false;
|
||||
}
|
||||
// Insert node into path
|
||||
PathGridnode &g_pos = getIndexElement(ipos);
|
||||
if (!g_pos.valid) {
|
||||
ERROR_TARGET << "Pathfinder: buildPath: invalid next pos detected, aborting" << std::endl;
|
||||
return false;
|
||||
}
|
||||
|
||||
PathGridnode &g_pos = getIndexElement(ipos);
|
||||
g_pos.totalcost = current_cost;
|
||||
g_pos.sourcedir = srcdir;
|
||||
g_pos.is_element = true;
|
||||
path.push_back(ipos);
|
||||
if (g_pos.source)
|
||||
// start node found, terminate
|
||||
return true;
|
||||
|
||||
level ++;
|
||||
|
||||
//check if target has been found
|
||||
if (g_pos.target) {
|
||||
m_min_target_distance = current_cost;
|
||||
DEBUG_OUT(LVL " Pathfinder: target found!" << std::endl);
|
||||
return true;
|
||||
// go to the node from which the pathfinder came
|
||||
ipos += g_pos.sourcedir;
|
||||
}
|
||||
|
||||
bool retval = false;
|
||||
ERROR_TARGET << "Pathfinder: buildPath: no source node found" << std::endl;
|
||||
return false;
|
||||
}
|
||||
|
||||
std::vector<v3s16> directions;
|
||||
|
||||
directions.emplace_back(1, 0, 0);
|
||||
directions.emplace_back(-1, 0, 0);
|
||||
directions.emplace_back(0, 0, 1);
|
||||
directions.emplace_back(0, 0, -1);
|
||||
|
||||
v3s16 direction = getDirHeuristic(directions, g_pos);
|
||||
|
||||
while (direction != v3s16(0, 0, 0) && (!retval)) {
|
||||
|
||||
if (direction != srcdir) {
|
||||
PathCost cost = g_pos.getCost(direction);
|
||||
|
||||
if (cost.valid) {
|
||||
direction.Y = cost.direction;
|
||||
|
||||
v3s16 ipos2 = ipos + direction;
|
||||
|
||||
if (!isValidIndex(ipos2)) {
|
||||
DEBUG_OUT(LVL " Pathfinder: " << PP(ipos2) <<
|
||||
" out of range, max=" << PP(m_limits.MaxEdge) << std::endl);
|
||||
direction = getDirHeuristic(directions, g_pos);
|
||||
continue;
|
||||
}
|
||||
|
||||
PathGridnode &g_pos2 = getIndexElement(ipos2);
|
||||
|
||||
if (!g_pos2.valid) {
|
||||
VERBOSE_TARGET << LVL "Pathfinder: no data for new position: "
|
||||
<< PP(ipos2) << std::endl;
|
||||
direction = getDirHeuristic(directions, g_pos);
|
||||
continue;
|
||||
}
|
||||
|
||||
assert(cost.value > 0);
|
||||
|
||||
int new_cost = current_cost + cost.value;
|
||||
|
||||
// check if there already is a smaller path
|
||||
if ((m_min_target_distance > 0) &&
|
||||
(m_min_target_distance < new_cost)) {
|
||||
DEBUG_OUT(LVL "Pathfinder:"
|
||||
" already longer than best already found path "
|
||||
<< PP(ipos2) << std::endl);
|
||||
return false;
|
||||
}
|
||||
|
||||
if ((g_pos2.totalcost < 0) ||
|
||||
(g_pos2.totalcost > new_cost)) {
|
||||
DEBUG_OUT(LVL "Pathfinder: updating path at: "<<
|
||||
PP(ipos2) << " from: " << g_pos2.totalcost << " to "<<
|
||||
new_cost << " srcdir=" <<
|
||||
PP(invert(direction))<< std::endl);
|
||||
if (updateCostHeuristic(ipos2, invert(direction),
|
||||
new_cost, level)) {
|
||||
retval = true;
|
||||
}
|
||||
}
|
||||
else {
|
||||
DEBUG_OUT(LVL "Pathfinder:"
|
||||
" already found shorter path to: "
|
||||
<< PP(ipos2) << std::endl);
|
||||
}
|
||||
}
|
||||
else {
|
||||
DEBUG_OUT(LVL "Pathfinder:"
|
||||
" not moving to invalid direction: "
|
||||
<< PP(direction) << std::endl);
|
||||
}
|
||||
/******************************************************************************/
|
||||
v3s16 Pathfinder::walkDownwards(v3s16 pos, unsigned int max_down) {
|
||||
if (max_down == 0)
|
||||
return pos;
|
||||
v3s16 testpos = v3s16(pos);
|
||||
MapNode node_at_pos = m_env->getMap().getNode(testpos);
|
||||
const NodeDefManager *ndef = m_env->getGameDef()->ndef();
|
||||
unsigned int down = 0;
|
||||
while ((node_at_pos.param0 != CONTENT_IGNORE) &&
|
||||
(!ndef->get(node_at_pos).walkable) &&
|
||||
(testpos.Y > m_limits.MinEdge.Y) &&
|
||||
(down <= max_down)) {
|
||||
testpos += v3s16(0, -1, 0);
|
||||
down++;
|
||||
node_at_pos = m_env->getMap().getNode(testpos);
|
||||
}
|
||||
//did we find surface?
|
||||
if ((testpos.Y >= m_limits.MinEdge.Y) &&
|
||||
(node_at_pos.param0 != CONTENT_IGNORE) &&
|
||||
(ndef->get(node_at_pos).walkable)) {
|
||||
if (down == 0) {
|
||||
pos = testpos;
|
||||
} else if ((down - 1) <= max_down) {
|
||||
//difference of y-pos +1 (target node is ABOVE solid node)
|
||||
testpos += v3s16(0, 1, 0);
|
||||
pos = testpos;
|
||||
}
|
||||
else {
|
||||
DEBUG_OUT(LVL "Pathfinder:"
|
||||
" skipping srcdir: "
|
||||
<< PP(direction) << std::endl);
|
||||
VERBOSE_TARGET << "Pos too far above ground: " <<
|
||||
"Index: " << PP(getIndexPos(pos)) <<
|
||||
"Realpos: " << PP(getRealPos(getIndexPos(pos))) << std::endl;
|
||||
}
|
||||
direction = getDirHeuristic(directions, g_pos);
|
||||
} else {
|
||||
DEBUG_OUT("Pathfinder: no surface found below pos" << std::endl);
|
||||
}
|
||||
return retval;
|
||||
}
|
||||
|
||||
/******************************************************************************/
|
||||
void Pathfinder::buildPath(std::vector<v3s16> &path, v3s16 pos, int level)
|
||||
{
|
||||
level ++;
|
||||
if (level > 700) {
|
||||
ERROR_TARGET
|
||||
<< LVL "Pathfinder: path is too long aborting" << std::endl;
|
||||
return;
|
||||
}
|
||||
|
||||
PathGridnode &g_pos = getIndexElement(pos);
|
||||
if (!g_pos.valid) {
|
||||
ERROR_TARGET
|
||||
<< LVL "Pathfinder: invalid next pos detected aborting" << std::endl;
|
||||
return;
|
||||
}
|
||||
|
||||
g_pos.is_element = true;
|
||||
|
||||
//check if source reached
|
||||
if (g_pos.source) {
|
||||
path.push_back(pos);
|
||||
return;
|
||||
}
|
||||
|
||||
buildPath(path, pos + g_pos.sourcedir, level);
|
||||
path.push_back(pos);
|
||||
}
|
||||
|
||||
/******************************************************************************/
|
||||
v3f Pathfinder::tov3f(v3s16 pos)
|
||||
{
|
||||
return v3f(BS * pos.X, BS * pos.Y, BS * pos.Z);
|
||||
return pos;
|
||||
}
|
||||
|
||||
#ifdef PATHFINDER_DEBUG
|
||||
@ -1268,7 +1359,7 @@ void Pathfinder::printYdir(PathDirections dir)
|
||||
for (int x = 0; x < m_max_index_x; x++) {
|
||||
if (getIdxElem(x, y, z).directions[dir].valid)
|
||||
std::cout << std::setw(4)
|
||||
<< getIdxElem(x, y, z).directions[dir].direction;
|
||||
<< getIdxElem(x, y, z).directions[dir].y_change;
|
||||
else
|
||||
std::cout << std::setw(4) << "-";
|
||||
}
|
||||
|
@ -1194,7 +1194,7 @@ int ModApiEnvMod::l_find_path(lua_State *L)
|
||||
unsigned int max_jump = luaL_checkint(L, 4);
|
||||
unsigned int max_drop = luaL_checkint(L, 5);
|
||||
PathAlgorithm algo = PA_PLAIN_NP;
|
||||
if (!lua_isnil(L, 6)) {
|
||||
if (!lua_isnoneornil(L, 6)) {
|
||||
std::string algorithm = luaL_checkstring(L,6);
|
||||
|
||||
if (algorithm == "A*")
|
||||
|
Loading…
Reference in New Issue
Block a user