Merge pull request #37039 from Chaosus/astar2d_cost

Implements estimate/compute_cost for AStar2D
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Rémi Verschelde 2020-03-19 08:19:59 +01:00 committed by GitHub
commit 256ac9a51d
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GPG key ID: 4AEE18F83AFDEB23
3 changed files with 219 additions and 16 deletions

View file

@ -399,7 +399,7 @@ bool AStar::_solve(Point *begin_point, Point *end_point) {
return found_route;
}
float AStar::_estimate_cost(int p_from_id, int p_to_id) {
real_t AStar::_estimate_cost(int p_from_id, int p_to_id) {
if (get_script_instance() && get_script_instance()->has_method(SceneStringNames::get_singleton()->_estimate_cost))
return get_script_instance()->call(SceneStringNames::get_singleton()->_estimate_cost, p_from_id, p_to_id);
@ -415,7 +415,7 @@ float AStar::_estimate_cost(int p_from_id, int p_to_id) {
return from_point->pos.distance_to(to_point->pos);
}
float AStar::_compute_cost(int p_from_id, int p_to_id) {
real_t AStar::_compute_cost(int p_from_id, int p_to_id) {
if (get_script_instance() && get_script_instance()->has_method(SceneStringNames::get_singleton()->_compute_cost))
return get_script_instance()->call(SceneStringNames::get_singleton()->_compute_cost, p_from_id, p_to_id);
@ -677,25 +677,195 @@ Vector2 AStar2D::get_closest_position_in_segment(const Vector2 &p_point) const {
return Vector2(p.x, p.y);
}
real_t AStar2D::_estimate_cost(int p_from_id, int p_to_id) {
if (get_script_instance() && get_script_instance()->has_method(SceneStringNames::get_singleton()->_estimate_cost))
return get_script_instance()->call(SceneStringNames::get_singleton()->_estimate_cost, p_from_id, p_to_id);
AStar::Point *from_point;
bool from_exists = astar.points.lookup(p_from_id, from_point);
ERR_FAIL_COND_V(!from_exists, 0);
AStar::Point *to_point;
bool to_exists = astar.points.lookup(p_to_id, to_point);
ERR_FAIL_COND_V(!to_exists, 0);
return from_point->pos.distance_to(to_point->pos);
}
real_t AStar2D::_compute_cost(int p_from_id, int p_to_id) {
if (get_script_instance() && get_script_instance()->has_method(SceneStringNames::get_singleton()->_compute_cost))
return get_script_instance()->call(SceneStringNames::get_singleton()->_compute_cost, p_from_id, p_to_id);
AStar::Point *from_point;
bool from_exists = astar.points.lookup(p_from_id, from_point);
ERR_FAIL_COND_V(!from_exists, 0);
AStar::Point *to_point;
bool to_exists = astar.points.lookup(p_to_id, to_point);
ERR_FAIL_COND_V(!to_exists, 0);
return from_point->pos.distance_to(to_point->pos);
}
Vector<Vector2> AStar2D::get_point_path(int p_from_id, int p_to_id) {
PackedVector3Array pv = astar.get_point_path(p_from_id, p_to_id);
int size = pv.size();
PackedVector2Array path;
path.resize(size);
AStar::Point *a;
bool from_exists = astar.points.lookup(p_from_id, a);
ERR_FAIL_COND_V(!from_exists, Vector<Vector2>());
AStar::Point *b;
bool to_exists = astar.points.lookup(p_to_id, b);
ERR_FAIL_COND_V(!to_exists, Vector<Vector2>());
if (a == b) {
Vector<Vector2> ret;
ret.push_back(Vector2(a->pos.x, a->pos.y));
return ret;
}
AStar::Point *begin_point = a;
AStar::Point *end_point = b;
bool found_route = _solve(begin_point, end_point);
if (!found_route) return Vector<Vector2>();
AStar::Point *p = end_point;
int pc = 1; // Begin point
while (p != begin_point) {
pc++;
p = p->prev_point;
}
Vector<Vector2> path;
path.resize(pc);
{
const Vector3 *r = pv.ptr();
Vector2 *w = path.ptrw();
for (int i = 0; i < size; i++) {
Vector3 p = r[i];
w[i] = Vector2(p.x, p.y);
AStar::Point *p2 = end_point;
int idx = pc - 1;
while (p2 != begin_point) {
w[idx--] = Vector2(p2->pos.x, p2->pos.y);
p2 = p2->prev_point;
}
w[0] = Vector2(p2->pos.x, p2->pos.y); // Assign first
}
return path;
}
Vector<int> AStar2D::get_id_path(int p_from_id, int p_to_id) {
return astar.get_id_path(p_from_id, p_to_id);
AStar::Point *a;
bool from_exists = astar.points.lookup(p_from_id, a);
ERR_FAIL_COND_V(!from_exists, Vector<int>());
AStar::Point *b;
bool to_exists = astar.points.lookup(p_to_id, b);
ERR_FAIL_COND_V(!to_exists, Vector<int>());
if (a == b) {
Vector<int> ret;
ret.push_back(a->id);
return ret;
}
AStar::Point *begin_point = a;
AStar::Point *end_point = b;
bool found_route = _solve(begin_point, end_point);
if (!found_route) return Vector<int>();
AStar::Point *p = end_point;
int pc = 1; // Begin point
while (p != begin_point) {
pc++;
p = p->prev_point;
}
Vector<int> path;
path.resize(pc);
{
int *w = path.ptrw();
p = end_point;
int idx = pc - 1;
while (p != begin_point) {
w[idx--] = p->id;
p = p->prev_point;
}
w[0] = p->id; // Assign first
}
return path;
}
bool AStar2D::_solve(AStar::Point *begin_point, AStar::Point *end_point) {
astar.pass++;
if (!end_point->enabled) return false;
bool found_route = false;
Vector<AStar::Point *> open_list;
SortArray<AStar::Point *, AStar::SortPoints> sorter;
begin_point->g_score = 0;
begin_point->f_score = _estimate_cost(begin_point->id, end_point->id);
open_list.push_back(begin_point);
while (!open_list.empty()) {
AStar::Point *p = open_list[0]; // The currently processed point
if (p == end_point) {
found_route = true;
break;
}
sorter.pop_heap(0, open_list.size(), open_list.ptrw()); // Remove the current point from the open list
open_list.remove(open_list.size() - 1);
p->closed_pass = astar.pass; // Mark the point as closed
for (OAHashMap<int, AStar::Point *>::Iterator it = p->neighbours.iter(); it.valid; it = p->neighbours.next_iter(it)) {
AStar::Point *e = *(it.value); // The neighbour point
if (!e->enabled || e->closed_pass == astar.pass) {
continue;
}
real_t tentative_g_score = p->g_score + _compute_cost(p->id, e->id) * e->weight_scale;
bool new_point = false;
if (e->open_pass != astar.pass) { // The point wasn't inside the open list.
e->open_pass = astar.pass;
open_list.push_back(e);
new_point = true;
} else if (tentative_g_score >= e->g_score) { // The new path is worse than the previous.
continue;
}
e->prev_point = p;
e->g_score = tentative_g_score;
e->f_score = e->g_score + _estimate_cost(e->id, end_point->id);
if (new_point) { // The position of the new points is already known.
sorter.push_heap(0, open_list.size() - 1, 0, e, open_list.ptrw());
} else {
sorter.push_heap(0, open_list.find(e), 0, e, open_list.ptrw());
}
}
}
return found_route;
}
void AStar2D::_bind_methods() {
@ -728,6 +898,9 @@ void AStar2D::_bind_methods() {
ClassDB::bind_method(D_METHOD("get_point_path", "from_id", "to_id"), &AStar2D::get_point_path);
ClassDB::bind_method(D_METHOD("get_id_path", "from_id", "to_id"), &AStar2D::get_id_path);
BIND_VMETHOD(MethodInfo(Variant::FLOAT, "_estimate_cost", PropertyInfo(Variant::INT, "from_id"), PropertyInfo(Variant::INT, "to_id")));
BIND_VMETHOD(MethodInfo(Variant::FLOAT, "_compute_cost", PropertyInfo(Variant::INT, "from_id"), PropertyInfo(Variant::INT, "to_id")));
}
AStar2D::AStar2D() {

View file

@ -43,6 +43,7 @@
class AStar : public Reference {
GDCLASS(AStar, Reference);
friend class AStar2D;
struct Point {
@ -124,8 +125,8 @@ class AStar : public Reference {
protected:
static void _bind_methods();
virtual float _estimate_cost(int p_from_id, int p_to_id);
virtual float _compute_cost(int p_from_id, int p_to_id);
virtual real_t _estimate_cost(int p_from_id, int p_to_id);
virtual real_t _compute_cost(int p_from_id, int p_to_id);
public:
int get_available_point_id() const;
@ -166,9 +167,14 @@ class AStar2D : public Reference {
GDCLASS(AStar2D, Reference);
AStar astar;
bool _solve(AStar::Point *begin_point, AStar::Point *end_point);
protected:
static void _bind_methods();
virtual real_t _estimate_cost(int p_from_id, int p_to_id);
virtual real_t _compute_cost(int p_from_id, int p_to_id);
public:
int get_available_point_id() const;

View file

@ -9,6 +9,30 @@
<tutorials>
</tutorials>
<methods>
<method name="_compute_cost" qualifiers="virtual">
<return type="float">
</return>
<argument index="0" name="from_id" type="int">
</argument>
<argument index="1" name="to_id" type="int">
</argument>
<description>
Called when computing the cost between two connected points.
Note that this function is hidden in the default [code]AStar2D[/code] class.
</description>
</method>
<method name="_estimate_cost" qualifiers="virtual">
<return type="float">
</return>
<argument index="0" name="from_id" type="int">
</argument>
<argument index="1" name="to_id" type="int">
</argument>
<description>
Called when estimating the cost between a point and the path's ending point.
Note that this function is hidden in the default [code]AStar2D[/code] class.
</description>
</method>
<method name="add_point">
<return type="void">
</return>