From 9250b5205a6c627dfa18b7870b454d74f8d9dae6 Mon Sep 17 00:00:00 2001
From: Elias Fleckenstein
 <54945686+EliasFleckenstein03@users.noreply.github.com>
Date: Tue, 29 Dec 2020 16:50:09 +0100
Subject: [PATCH] Add minetest.get_objects_in_area (#10668)

---
 doc/lua_api.txt                |  3 +++
 src/script/lua_api/l_env.cpp   | 26 ++++++++++++++++++++++++++
 src/script/lua_api/l_env.h     |  3 +++
 src/server/activeobjectmgr.cpp | 15 +++++++++++++++
 src/server/activeobjectmgr.h   |  3 +++
 src/serverenvironment.h        |  7 +++++++
 6 files changed, 57 insertions(+)

diff --git a/doc/lua_api.txt b/doc/lua_api.txt
index 708d6b0bc..800fc0c24 100644
--- a/doc/lua_api.txt
+++ b/doc/lua_api.txt
@@ -4891,6 +4891,9 @@ Environment access
 * `minetest.get_objects_inside_radius(pos, radius)`: returns a list of
   ObjectRefs.
     * `radius`: using an euclidean metric
+* `minetest.get_objects_in_area(pos1, pos2)`: returns a list of
+  ObjectRefs.
+     * `pos1` and `pos2` are the min and max positions of the area to search.
 * `minetest.set_timeofday(val)`
     * `val` is between `0` and `1`; `0` for midnight, `0.5` for midday
 * `minetest.get_timeofday()`
diff --git a/src/script/lua_api/l_env.cpp b/src/script/lua_api/l_env.cpp
index 021ef2ea7..c75fc8dc7 100644
--- a/src/script/lua_api/l_env.cpp
+++ b/src/script/lua_api/l_env.cpp
@@ -743,6 +743,31 @@ int ModApiEnvMod::l_get_objects_inside_radius(lua_State *L)
 	return 1;
 }
 
+// get_objects_in_area(pos, minp, maxp)
+int ModApiEnvMod::l_get_objects_in_area(lua_State *L)
+{
+	GET_ENV_PTR;
+	ScriptApiBase *script = getScriptApiBase(L);
+	
+	v3f minp = read_v3f(L, 1) * BS;
+	v3f maxp = read_v3f(L, 2) * BS;
+	aabb3f box(minp, maxp);
+	box.repair();
+	std::vector<ServerActiveObject *> objs;
+
+	auto include_obj_cb = [](ServerActiveObject *obj){ return !obj->isGone(); };
+	env->getObjectsInArea(objs, box, include_obj_cb);
+
+	int i = 0;
+	lua_createtable(L, objs.size(), 0);
+	for (const auto obj : objs) {
+		// Insert object reference into table
+		script->objectrefGetOrCreate(L, obj);
+		lua_rawseti(L, -2, ++i);
+	}
+	return 1;
+}
+
 // set_timeofday(val)
 // val = 0...1
 int ModApiEnvMod::l_set_timeofday(lua_State *L)
@@ -1413,6 +1438,7 @@ void ModApiEnvMod::Initialize(lua_State *L, int top)
 	API_FCT(get_node_timer);
 	API_FCT(get_connected_players);
 	API_FCT(get_player_by_name);
+	API_FCT(get_objects_in_area);
 	API_FCT(get_objects_inside_radius);
 	API_FCT(set_timeofday);
 	API_FCT(get_timeofday);
diff --git a/src/script/lua_api/l_env.h b/src/script/lua_api/l_env.h
index 7f212b5fc..42c2d64f8 100644
--- a/src/script/lua_api/l_env.h
+++ b/src/script/lua_api/l_env.h
@@ -114,6 +114,9 @@ private:
 
 	// get_objects_inside_radius(pos, radius)
 	static int l_get_objects_inside_radius(lua_State *L);
+	
+	// get_objects_in_area(pos, minp, maxp)
+	static int l_get_objects_in_area(lua_State *L);
 
 	// set_timeofday(val)
 	// val = 0...1
diff --git a/src/server/activeobjectmgr.cpp b/src/server/activeobjectmgr.cpp
index 1b8e31409..acd6611f4 100644
--- a/src/server/activeobjectmgr.cpp
+++ b/src/server/activeobjectmgr.cpp
@@ -127,6 +127,21 @@ void ActiveObjectMgr::getObjectsInsideRadius(const v3f &pos, float radius,
 	}
 }
 
+void ActiveObjectMgr::getObjectsInArea(const aabb3f &box,
+		std::vector<ServerActiveObject *> &result,
+		std::function<bool(ServerActiveObject *obj)> include_obj_cb)
+{
+	for (auto &activeObject : m_active_objects) {
+		ServerActiveObject *obj = activeObject.second;
+		const v3f &objectpos = obj->getBasePosition();
+		if (!box.isPointInside(objectpos))
+			continue;
+
+		if (!include_obj_cb || include_obj_cb(obj))
+			result.push_back(obj);
+	}
+}
+
 void ActiveObjectMgr::getAddedActiveObjectsAroundPos(const v3f &player_pos, f32 radius,
 		f32 player_radius, std::set<u16> &current_objects,
 		std::queue<u16> &added_objects)
diff --git a/src/server/activeobjectmgr.h b/src/server/activeobjectmgr.h
index bc2085499..d43f5643c 100644
--- a/src/server/activeobjectmgr.h
+++ b/src/server/activeobjectmgr.h
@@ -38,6 +38,9 @@ public:
 	void getObjectsInsideRadius(const v3f &pos, float radius,
 			std::vector<ServerActiveObject *> &result,
 			std::function<bool(ServerActiveObject *obj)> include_obj_cb);
+	void getObjectsInArea(const aabb3f &box,
+			std::vector<ServerActiveObject *> &result,
+			std::function<bool(ServerActiveObject *obj)> include_obj_cb);
 
 	void getAddedActiveObjectsAroundPos(const v3f &player_pos, f32 radius,
 			f32 player_radius, std::set<u16> &current_objects,
diff --git a/src/serverenvironment.h b/src/serverenvironment.h
index cfd5b8f3e..c76d34a37 100644
--- a/src/serverenvironment.h
+++ b/src/serverenvironment.h
@@ -331,6 +331,13 @@ public:
 	{
 		return m_ao_manager.getObjectsInsideRadius(pos, radius, objects, include_obj_cb);
 	}
+	
+	// Find all active objects inside a box
+	void getObjectsInArea(std::vector<ServerActiveObject *> &objects, const aabb3f &box,
+			std::function<bool(ServerActiveObject *obj)> include_obj_cb)
+	{
+		return m_ao_manager.getObjectsInArea(box, objects, include_obj_cb);
+	}
 
 	// Clear objects, loading and going through every MapBlock
 	void clearObjects(ClearObjectsMode mode);