Merge pull request #21492 from Maykeye/astar

Changed A* exit condition, added 2 tests for it

4 files changed, 169 insertions, 17 deletions

diff --git a/core/math/a_star.cpp b/core/math/a_star.cpp
index e4f93289e9..451c45cade 100644
--- a/core/math/a_star.cpp
+++ b/core/math/a_star.cpp
@@ -250,14 +250,9 @@ bool AStar::_solve(Point *begin_point, Point *end_point) {
 		n->distance = _compute_cost(begin_point->id, n->id) * n->weight_scale;
 		n->last_pass = pass;
 		open_list.add(&n->list);
-
-		if (end_point == n) {
-			found_route = true;
-			break;
-		}
 	}
 
-	while (!found_route) {
+	while (true) {
 
 		if (open_list.first() == NULL) {
 			// No path found
@@ -277,13 +272,16 @@ bool AStar::_solve(Point *begin_point, Point *end_point) {
 			cost += _estimate_cost(p->id, end_point->id);
 
 			if (cost < least_cost) {
-
 				least_cost_point = E;
 				least_cost = cost;
 			}
 		}
 
 		Point *p = least_cost_point->self();
+		if (p == end_point) {
+			found_route = true;
+			break;
+		}
 
 		for (Set<Point *>::Element *E = p->neighbours.front(); E; E = E->next()) {
 
@@ -295,7 +293,6 @@ bool AStar::_solve(Point *begin_point, Point *end_point) {
 				// Already visited, is this cheaper?
 
 				if (e->distance > distance) {
-
 					e->prev_point = p;
 					e->distance = distance;
 				}
@@ -306,18 +303,9 @@ bool AStar::_solve(Point *begin_point, Point *end_point) {
 				e->distance = distance;
 				e->last_pass = pass; // Mark as used
 				open_list.add(&e->list);
-
-				if (e == end_point) {
-					// End reached; stop algorithm
-					found_route = true;
-					break;
-				}
 			}
 		}
 
-		if (found_route)
-			break;
-
 		open_list.remove(least_cost_point);
 	}
 
diff --git a/main/tests/test_astar.cpp b/main/tests/test_astar.cpp
new file mode 100644
index 0000000000..0f034c78f7
--- /dev/null
+++ b/main/tests/test_astar.cpp
@@ -0,0 +1,116 @@
+/*************************************************************************/
+/*  test_astar.cpp                                                       */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "a_star.h"
+#include "os/os.h"
+#include <stdio.h>
+
+#include "test_astar.h"
+
+namespace TestAStar {
+
+class ABCX : public AStar {
+public:
+	enum { A,
+		B,
+		C,
+		X };
+
+	ABCX() {
+		add_point(A, Vector3(0, 0, 0));
+		add_point(B, Vector3(1, 0, 0));
+		add_point(C, Vector3(0, 1, 0));
+		add_point(X, Vector3(0, 0, 1));
+		connect_points(A, B);
+		connect_points(A, C);
+		connect_points(B, C);
+		connect_points(X, A);
+	}
+
+	// Disable heuristic completely
+	float _compute_cost(int p_from, int p_to) {
+		if (p_from == A && p_to == C) {
+			return 1000;
+		}
+		return 100;
+	}
+};
+
+bool test_abc() {
+	ABCX abcx;
+	PoolVector<int> path = abcx.get_id_path(ABCX::A, ABCX::C);
+	bool ok = path.size() == 3;
+	int i = 0;
+	ok = ok && path[i++] == ABCX::A;
+	ok = ok && path[i++] == ABCX::B;
+	ok = ok && path[i++] == ABCX::C;
+	return ok;
+}
+
+bool test_abcx() {
+	ABCX abcx;
+	PoolVector<int> path = abcx.get_id_path(ABCX::X, ABCX::C);
+	bool ok = path.size() == 4;
+	int i = 0;
+	ok = ok && path[i++] == ABCX::X;
+	ok = ok && path[i++] == ABCX::A;
+	ok = ok && path[i++] == ABCX::B;
+	ok = ok && path[i++] == ABCX::C;
+	return ok;
+}
+
+typedef bool (*TestFunc)(void);
+
+TestFunc test_funcs[] = {
+	test_abc,
+	test_abcx,
+	NULL
+};
+
+MainLoop *test() {
+	int count = 0;
+	int passed = 0;
+
+	while (true) {
+		if (!test_funcs[count])
+			break;
+		bool pass = test_funcs[count]();
+		if (pass)
+			passed++;
+		OS::get_singleton()->print("\t%s\n", pass ? "PASS" : "FAILED");
+
+		count++;
+	}
+	OS::get_singleton()->print("\n");
+	OS::get_singleton()->print("Passed %i of %i tests\n", passed, count);
+	return NULL;
+}
+
+} // namespace TestAStar
diff --git a/main/tests/test_astar.h b/main/tests/test_astar.h
new file mode 100644
index 0000000000..6029742017
--- /dev/null
+++ b/main/tests/test_astar.h
@@ -0,0 +1,41 @@
+/*************************************************************************/
+/*  test_astar.h                                                         */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef TEST_ASTAR_H
+#define TEST_ASTAR_H
+
+#include "os/main_loop.h"
+
+namespace TestAStar {
+
+MainLoop *test();
+}
+
+#endif
diff --git a/main/tests/test_main.cpp b/main/tests/test_main.cpp
index cd70b95a28..714a254371 100644
--- a/main/tests/test_main.cpp
+++ b/main/tests/test_main.cpp
@@ -33,6 +33,7 @@
 
 #ifdef DEBUG_ENABLED
 
+#include "test_astar.h"
 #include "test_gdscript.h"
 #include "test_gui.h"
 #include "test_image.h"
@@ -64,6 +65,7 @@ const char **tests_get_names() {
 		"gd_bytecode",
 		"image",
 		"ordered_hash_map",
+		"astar",
 		NULL
 	};
 
@@ -149,6 +151,11 @@ MainLoop *test_main(String p_test, const List<String> &p_args) {
 		return TestOrderedHashMap::test();
 	}
 
+	if (p_test == "astar") {
+
+		return TestAStar::test();
+	}
+
 	return NULL;
 }