Prevent objects from colliding with own child attachments (#7610)

Also, use a better distance calculation for 'collide with objects'. Fixes the issue of a vehicle occasionally colliding with its own driver, causing one of the velocity components to be set to zero.
minetest · Aug 5, 2018 · ee63b94f2c9e176f549c4446391e4c59f5a5be53 · ee63b94
1 parent 88efebd
commit ee63b94f2c9e176f549c4446391e4c59f5a5be53
Unified Split

Showing with 28 additions and 14 deletions.

+1 −0 src/clientobject.h

+16 −6 src/collision.cpp

+2 −2 src/content_cao.h

+4 −5 src/content_sao.cpp

+4 −1 src/content_sao.h

+1 −0 src/serverobject.h
diff --git a/src/clientobject.h b/src/clientobject.h
@@ -51,6 +51,7 @@ class ClientActiveObject : public ActiveObject
 	virtual scene::ISceneNode *getSceneNode() { return NULL; }
 	virtual scene::IAnimatedMeshSceneNode *getAnimatedMeshSceneNode() { return NULL; }
 	virtual bool isLocalPlayer() const {return false;}
+  
+	virtual ClientActiveObject *getParent() const { return nullptr; };
 	virtual void setAttachments() {}
 	virtual bool doShowSelectionBox(){return true;}

diff --git a/src/collision.cpp b/src/collision.cpp
@@ -360,11 +360,16 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
 #ifndef SERVER
 		ClientEnvironment *c_env = dynamic_cast<ClientEnvironment*>(env);
 		if (c_env != 0) {
-  
-			f32 distance = speed_f->getLength();
+  
+			// Calculate distance by speed, add own extent and 1.5m of tolerance
+  
+			f32 distance = speed_f->getLength() * dtime +
+  
+				box_0.getExtent().getLength() + 1.5f * BS;
 			std::vector<DistanceSortedActiveObject> clientobjects;
-  
-			c_env->getActiveObjects(*pos_f, distance * 1.5f, clientobjects);
+  
+			c_env->getActiveObjects(*pos_f, distance, clientobjects);
+  
+
 			for (auto &clientobject : clientobjects) {
-  
-				if (!self || (self != clientobject.obj)) {
+  
+				// Do collide with everything but itself and the parent CAO
+  
+				if (!self || (self != clientobject.obj &&
+  
+						self != clientobject.obj->getParent())) {
 					objects.push_back((ActiveObject*) clientobject.obj);
 				}
 			}
@@ -374,12 +379,17 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
 		{
 			ServerEnvironment *s_env = dynamic_cast<ServerEnvironment*>(env);
 			if (s_env != NULL) {
-  
-				f32 distance = speed_f->getLength();
+  
+				// Calculate distance by speed, add own extent and 1.5m of tolerance
+  
+				f32 distance = speed_f->getLength() * dtime +
+  
+					box_0.getExtent().getLength() + 1.5f * BS;
 				std::vector<u16> s_objects;
-  
-				s_env->getObjectsInsideRadius(s_objects, *pos_f, distance * 1.5f);
+  
+				s_env->getObjectsInsideRadius(s_objects, *pos_f, distance);
+  
+
 				for (u16 obj_id : s_objects) {
 					ServerActiveObject *current = s_env->getActiveObject(obj_id);
-  
-					if (!self || (self != current)) {
+  
+
+  
+					if (!self || (self != current &&
+  
+							self != current->getParent())) {
 						objects.push_back((ActiveObject*)current);
 					}
 				}

diff --git a/src/content_cao.h b/src/content_cao.h
@@ -139,8 +139,6 @@ class GenericCAO : public ClientActiveObject
 	void processInitData(const std::string &data);
-  
-	ClientActiveObject *getParent() const;
-  
-
 	bool getCollisionBox(aabb3f *toset) const;
 	bool collideWithObjects() const;
@@ -181,6 +179,8 @@ class GenericCAO : public ClientActiveObject
 	void setChildrenVisible(bool toset);
+  
+	ClientActiveObject *getParent() const;
+  
+
 	void setAttachments();
 	void removeFromScene(bool permanent);

diff --git a/src/content_sao.cpp b/src/content_sao.cpp
@@ -118,15 +118,14 @@ UnitSAO::UnitSAO(ServerEnvironment *env, v3f pos):
 	m_armor_groups["fleshy"] = 100;
 }
-  
-bool UnitSAO::isAttached() const
+  
+ServerActiveObject *UnitSAO::getParent() const
 {
 	if (!m_attachment_parent_id)
-  
-		return false;
+  
+		return nullptr;
 	// Check if the parent still exists
 	ServerActiveObject *obj = m_env->getActiveObject(m_attachment_parent_id);
-  
-	if (obj)
-  
-		return true;
-  
-	return false;
+  
+
+  
+	return obj;
 }
 void UnitSAO::setArmorGroups(const ItemGroupList &armor_groups)

diff --git a/src/content_sao.h b/src/content_sao.h
@@ -42,7 +42,9 @@ class UnitSAO: public ServerActiveObject
 	// Use a function, if isDead can be defined by other conditions
 	bool isDead() const { return m_hp == 0; }
-  
-	bool isAttached() const;
+  
+	inline bool isAttached() const
+  
+	{ return getParent(); }
+  
+
 	void setArmorGroups(const ItemGroupList &armor_groups);
 	const ItemGroupList &getArmorGroups();
 	void setAnimation(v2f frame_range, float frame_speed, float frame_blend, bool frame_loop);
@@ -57,6 +59,7 @@ class UnitSAO: public ServerActiveObject
 	void addAttachmentChild(int child_id);
 	void removeAttachmentChild(int child_id);
 	const std::unordered_set<int> &getAttachmentChildIds();
+  
+	ServerActiveObject *getParent() const;
 	ObjectProperties* accessObjectProperties();
 	void notifyObjectPropertiesModified();
 protected:

diff --git a/src/serverobject.h b/src/serverobject.h
@@ -173,6 +173,7 @@ class ServerActiveObject : public ActiveObject
 	{}
 	virtual const std::unordered_set<int> &getAttachmentChildIds()
 	{ static const std::unordered_set<int> rv; return rv; }
+  
+	virtual ServerActiveObject *getParent() const { return nullptr; }
 	virtual ObjectProperties* accessObjectProperties()
 	{ return NULL; }
 	virtual void notifyObjectPropertiesModified()