ABM without_neighbors (#14116)

src/script/cpp_api/s_env.cpp

@@ -34,10 +34,11 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 
 class LuaABM : public ActiveBlockModifier {
 private:
-	int m_id;
+	const int m_id;
 
 	std::vector<std::string> m_trigger_contents;
 	std::vector<std::string> m_required_neighbors;
+	std::vector<std::string> m_without_neighbors;
 	float m_trigger_interval;
 	u32 m_trigger_chance;
 	bool m_simple_catch_up;
@@ -47,11 +48,13 @@ public:
 	LuaABM(int id,
 			const std::vector<std::string> &trigger_contents,
 			const std::vector<std::string> &required_neighbors,
+			const std::vector<std::string> &without_neighbors,
 			float trigger_interval, u32 trigger_chance, bool simple_catch_up,
 			s16 min_y, s16 max_y):
 		m_id(id),
 		m_trigger_contents(trigger_contents),
 		m_required_neighbors(required_neighbors),
+		m_without_neighbors(without_neighbors),
 		m_trigger_interval(trigger_interval),
 		m_trigger_chance(trigger_chance),
 		m_simple_catch_up(simple_catch_up),
@@ -67,6 +70,10 @@ public:
 	{
 		return m_required_neighbors;
 	}
+	virtual const std::vector<std::string> &getWithoutNeighbors() const
+	{
+		return m_without_neighbors;
+	}
 	virtual float getTriggerInterval()
 	{
 		return m_trigger_interval;
@@ -230,6 +237,11 @@ void ScriptApiEnv::readABMs()
 		read_nodenames(L, -1, required_neighbors);
 		lua_pop(L, 1);
 
+		std::vector<std::string> without_neighbors;
+		lua_getfield(L, current_abm, "without_neighbors");
+		read_nodenames(L, -1, without_neighbors);
+		lua_pop(L, 1);
+
 		float trigger_interval = 10.0;
 		getfloatfield(L, current_abm, "interval", trigger_interval);
 
@@ -250,7 +262,8 @@ void ScriptApiEnv::readABMs()
 		lua_pop(L, 1);
 
 		LuaABM *abm = new LuaABM(id, trigger_contents, required_neighbors,
-			trigger_interval, trigger_chance, simple_catch_up, min_y, max_y);
+			without_neighbors, trigger_interval, trigger_chance,
+			simple_catch_up, min_y, max_y);
 
 		env->addActiveBlockModifier(abm);
 

src/serverenvironment.cpp

@@ -827,6 +827,7 @@ struct ActiveABM
 {
 	ActiveBlockModifier *abm;
 	std::vector<content_t> required_neighbors;
+	std::vector<content_t> without_neighbors;
 	int chance;
 	s16 min_y, max_y;
 };
@@ -885,6 +886,10 @@ public:
 				ndef->getIds(s, aabm.required_neighbors);
 			SORT_AND_UNIQUE(aabm.required_neighbors);
 
+			for (const auto &s : abm->getWithoutNeighbors())
+				ndef->getIds(s, aabm.without_neighbors);
+			SORT_AND_UNIQUE(aabm.without_neighbors);
+
 			// Trigger contents
 			std::vector<content_t> ids;
 			for (const auto &s : abm->getTriggerContents())
@@ -996,8 +1001,11 @@ public:
 					continue;
 
 				// Check neighbors
-				if (!aabm.required_neighbors.empty()) {
+				const bool check_required_neighbors = !aabm.required_neighbors.empty();
+				const bool check_without_neighbors = !aabm.without_neighbors.empty();
+				if (check_required_neighbors || check_without_neighbors) {
 					v3s16 p1;
+					bool have_required = false;
 					for(p1.X = p0.X-1; p1.X <= p0.X+1; p1.X++)
 					for(p1.Y = p0.Y-1; p1.Y <= p0.Y+1; p1.Y++)
 					for(p1.Z = p0.Z-1; p1.Z <= p0.Z+1; p1.Z++)
@@ -1015,12 +1023,25 @@ public:
 							MapNode n = map->getNode(p1 + block->getPosRelative());
 							c = n.getContent();
 						}
-						if (CONTAINS(aabm.required_neighbors, c))
-							goto neighbor_found;
+						if (check_required_neighbors && !have_required) {
+							if (CONTAINS(aabm.required_neighbors, c)) {
+								if (!check_without_neighbors)
+									goto neighbor_found;
+								have_required = true;
+							}
+						}
+						if (check_without_neighbors) {
+							if (CONTAINS(aabm.without_neighbors, c))
+								goto neighbor_invalid;
+						}
 					}
+					if (have_required || !check_required_neighbors)
+						goto neighbor_found;
 					// No required neighbor found
+					neighbor_invalid:
 					continue;
 				}
+
 				neighbor_found:
 
 				abms_run++;

src/serverenvironment.h

@@ -63,6 +63,9 @@ public:
 	// Set of required neighbors (trigger doesn't happen if none are found)
 	// Empty = do not check neighbors
 	virtual const std::vector<std::string> &getRequiredNeighbors() const = 0;
+	// Set of without neighbors (trigger doesn't happen if any are found)
+	// Empty = do not check neighbors
+	virtual const std::vector<std::string> &getWithoutNeighbors() const = 0;
 	// Trigger interval in seconds
 	virtual float getTriggerInterval() = 0;
 	// Random chance of (1 / return value), 0 is disallowed

src/unittest/test_servermodmanager.cpp

@@ -122,7 +122,7 @@ void TestServerModManager::testGetMods()
 	ServerModManager sm(m_worlddir);
 	const auto &mods = sm.getMods();
 	// `ls ./games/devtest/mods | wc -l` + 1 (test mod)
-	UASSERTEQ(std::size_t, mods.size(), 32 + 1);
+	UASSERTEQ(std::size_t, mods.size(), 33 + 1);
 
 	// Ensure we found basenodes mod (part of devtest)
 	// and test_mod (for testing MINETEST_MOD_PATH).