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);
}
bool Pathfinder::updateAllCosts(v3s16 ipos,
v3s16 srcdir,
int current_cost,
int level)
{
PathGridnode &g_pos = getIndexElement(ipos);
g_pos.totalcost = current_cost;
g_pos.sourcedir = srcdir;
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;
}
bool retval = false;
std::vector<v3s16> directions;
directions.push_back(v3s16( 1,0, 0));
directions.push_back(v3s16(-1,0, 0));
directions.push_back(v3s16( 0,0, 1));
directions.push_back(v3s16( 0,0,-1));
for (unsigned int i=0; i < directions.size(); i++) {
if (directions[i] != srcdir) {
PathCost cost = g_pos.getCost(directions[i]);
if (cost.valid) {
directions[i].Y = cost.direction;
v3s16 ipos2 = ipos + directions[i];
if (!isValidIndex(ipos2)) {
DEBUG_OUT(LVL " Pathfinder: " << PP(ipos2) <<
" out of range, max=" << PP(m_limits.MaxEdge) << std::endl);
continue;
}
PathGridnode &g_pos2 = getIndexElement(ipos2);
if (!g_pos2.valid) {
VERBOSE_TARGET << LVL "Pathfinder: no data for new position: "
<< PP(ipos2) << std::endl;
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)) {
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 << std::endl);
if (updateAllCosts(ipos2, invert(directions[i]),
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(directions[i]) << std::endl);
}
}
}
return retval;
}
std::vector<v3s16> Pathfinder::getPath(ServerEnvironment *env,
v3s16 source,
v3s16 destination,
unsigned int searchdistance,
unsigned int max_jump,
unsigned int max_drop,
PathAlgorithm algo)
{
#ifdef PATHFINDER_CALC_TIME
timespec ts;
clock_gettime(CLOCK_REALTIME, &ts);
#endif
std::vector<v3s16> retval;
//check parameters
if (env == 0) {
ERROR_TARGET << "missing environment pointer" << std::endl;
return retval;
}
m_searchdistance = searchdistance;
m_env = env;
m_maxjump = max_jump;
m_maxdrop = max_drop;
m_start = source;
m_destination = destination;
m_min_target_distance = -1;
m_prefetch = true;
if (algo == PA_PLAIN_NP) {
m_prefetch = false;
}
int min_x = MYMIN(source.X, destination.X);
int max_x = MYMAX(source.X, destination.X);
int min_y = MYMIN(source.Y, destination.Y);
int max_y = MYMAX(source.Y, destination.Y);
int min_z = MYMIN(source.Z, destination.Z);
int max_z = MYMAX(source.Z, destination.Z);
m_limits.MinEdge.X = min_x - searchdistance;
m_limits.MinEdge.Y = min_y - searchdistance;
m_limits.MinEdge.Z = min_z - searchdistance;
m_limits.MaxEdge.X = max_x + searchdistance;
m_limits.MaxEdge.Y = max_y + searchdistance;
m_limits.MaxEdge.Z = max_z + searchdistance;
v3s16 diff = m_limits.MaxEdge - m_limits.MinEdge;
m_max_index_x = diff.X;
m_max_index_y = diff.Y;
m_max_index_z = diff.Z;
delete m_nodes_container;
if (diff.getLength() > 5) {
m_nodes_container = new MapGridNodeContainer(this);
} else {
m_nodes_container = new ArrayGridNodeContainer(this, diff);
}
#ifdef PATHFINDER_DEBUG
printType();
printCost();
printYdir();
#endif
//validate and mark start and end pos
v3s16 StartIndex = getIndexPos(source);
v3s16 EndIndex = getIndexPos(destination);
PathGridnode &startpos = getIndexElement(StartIndex);
PathGridnode &endpos = getIndexElement(EndIndex);
if (!startpos.valid) {
VERBOSE_TARGET << "invalid startpos" <<
"Index: " << PP(StartIndex) <<
"Realpos: " << PP(getRealPos(StartIndex)) << std::endl;
return retval;
}
if (!endpos.valid) {
VERBOSE_TARGET << "invalid stoppos" <<
"Index: " << PP(EndIndex) <<
"Realpos: " << PP(getRealPos(EndIndex)) << std::endl;
return retval;
}
endpos.target = true;
startpos.source = true;
startpos.totalcost = 0;
bool update_cost_retval = false;
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);
break;
default:
ERROR_TARGET << "missing PathAlgorithm"<< std::endl;
break;
}
if (update_cost_retval) {
#ifdef PATHFINDER_DEBUG
std::cout << "Path to target found!" << std::endl;
printPathLen();
#endif
//find path
std::vector<v3s16> path;
buildPath(path, EndIndex, 0);
#ifdef PATHFINDER_DEBUG
std::cout << "Full index path:" << std::endl;
printPath(path);
#endif
//finalize path
std::vector<v3s16> full_path;
for (std::vector<v3s16>::iterator i = path.begin();
i != path.end(); ++i) {
full_path.push_back(getIndexElement(*i).pos);
}
#ifdef PATHFINDER_DEBUG
std::cout << "full path:" << std::endl;
printPath(full_path);
#endif
#ifdef PATHFINDER_CALC_TIME
timespec ts2;
clock_gettime(CLOCK_REALTIME, &ts2);
int ms = (ts2.tv_nsec - ts.tv_nsec)/(1000*1000);
int us = ((ts2.tv_nsec - ts.tv_nsec) - (ms*1000*1000))/1000;
int ns = ((ts2.tv_nsec - ts.tv_nsec) - ( (ms*1000*1000) + (us*1000)));
std::cout << "Calculating path took: " << (ts2.tv_sec - ts.tv_sec) <<
"s " << ms << "ms " << us << "us " << ns << "ns " << std::endl;
#endif
return full_path;
}
else {
#ifdef PATHFINDER_DEBUG
printPathLen();
#endif
ERROR_TARGET << "failed to update cost map"<< std::endl;
}
//return
return retval;
}
bool pathfinder::update_cost_heuristic( v3s16 ipos,
v3s16 srcdir,
int current_cost,
int level) {
path_gridnode& g_pos = getIndexElement(ipos);
g_pos.totalcost = current_cost;
g_pos.sourcedir = srcdir;
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;
}
bool retval = false;
std::vector<v3s16> directions;
directions.push_back(v3s16( 1,0, 0));
directions.push_back(v3s16(-1,0, 0));
directions.push_back(v3s16( 0,0, 1));
directions.push_back(v3s16( 0,0,-1));
v3s16 direction = get_dir_heuristic(directions,g_pos);
while (direction != v3s16(0,0,0) && (!retval)) {
if (direction != srcdir) {
path_cost cost = g_pos.get_cost(direction);
if (cost.valid) {
direction.Y = cost.direction;
v3s16 ipos2 = ipos + direction;
if (!valid_index(ipos2)) {
DEBUG_OUT(LVL " Pathfinder: " << PPOS(ipos2) <<
" out of range (" << m_limits.X.max << "," <<
m_limits.Y.max << "," << m_limits.Z.max
<<")" << std::endl);
direction = get_dir_heuristic(directions,g_pos);
continue;
}
path_gridnode& g_pos2 = getIndexElement(ipos2);
if (!g_pos2.valid) {
VERBOSE_TARGET << LVL "Pathfinder: no data for new position: "
<< PPOS(ipos2) << std::endl;
direction = get_dir_heuristic(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 "
<< PPOS(ipos2) << std::endl);
return false;
}
if ((g_pos2.totalcost < 0) ||
(g_pos2.totalcost > new_cost)) {
DEBUG_OUT(LVL "Pathfinder: updating path at: "<<
PPOS(ipos2) << " from: " << g_pos2.totalcost << " to "<<
new_cost << " srcdir=" <<
PPOS(invert(direction))<< std::endl);
if (update_cost_heuristic(ipos2,invert(direction),
new_cost,level)) {
retval = true;
}
}
else {
DEBUG_OUT(LVL "Pathfinder:"
" already found shorter path to: "
<< PPOS(ipos2) << std::endl);
}
}
else {
DEBUG_OUT(LVL "Pathfinder:"
" not moving to invalid direction: "
<< PPOS(direction) << std::endl);
}
}
else {
DEBUG_OUT(LVL "Pathfinder:"
" skipping srcdir: "
<< PPOS(direction) << std::endl);
}
direction = get_dir_heuristic(directions,g_pos);
}
return retval;
}
