BGE: Add physics constraints replication

This patch will add a physics constraints replication for group instances
(dupli group).
It also fix crashing when when a group instance is made from a linked
group instance and both are on the active layer.

Initial patch T31443 from moerdn (Martin Sell).

Reviewers: lordloki, sergof, moguri, sybren

Reviewed By: moguri, sybren

Differential Revision: https://developer.blender.org/D658

3 files changed, 31 insertions, 0 deletions

diff --git a/source/gameengine/Ketsji/KX_GameObject.cpp b/source/gameengine/Ketsji/KX_GameObject.cpp
index 71af263bf46..c8fc64f4679 100644
--- a/source/gameengine/Ketsji/KX_GameObject.cpp
+++ b/source/gameengine/Ketsji/KX_GameObject.cpp
@@ -292,6 +292,21 @@ void KX_GameObject::SetDupliGroupObject(KX_GameObject* obj)
 	m_pDupliGroupObject = obj;
 }
 
+void KX_GameObject::AddConstraint(bRigidBodyJointConstraint *cons)
+{
+	m_constraints.push_back(cons);
+}
+
+std::vector<bRigidBodyJointConstraint*> KX_GameObject::GetConstraints()
+{
+	return m_constraints;
+}
+
+void KX_GameObject::ClearConstraints()
+{
+	m_constraints.clear();
+}
+
 KX_GameObject* KX_GameObject::GetParent()
 {
 	KX_GameObject* result = NULL;
diff --git a/source/gameengine/Ketsji/KX_GameObject.h b/source/gameengine/Ketsji/KX_GameObject.h
index 7d1a934bcec..132e72c45e2 100644
--- a/source/gameengine/Ketsji/KX_GameObject.h
+++ b/source/gameengine/Ketsji/KX_GameObject.h
@@ -49,6 +49,7 @@
 #include "CTR_HashedPtr.h"
 #include "KX_Scene.h"
 #include "KX_KetsjiEngine.h" /* for m_anim_framerate */
+#include "DNA_constraint_types.h" /* for constraint replication */
 #include "DNA_object_types.h"
 #include "SCA_LogicManager.h" /* for ConvertPythonToGameObject to search object names */
 
@@ -117,6 +118,7 @@ protected:
 	SG_Node*							m_pSGNode;
 
 	MT_CmMatrix4x4						m_OpenGL_4x4Matrix;
+	std::vector<bRigidBodyJointConstraint*>	m_constraints;
 
 	KX_ObstacleSimulation*				m_pObstacleSimulation;
 
@@ -193,6 +195,14 @@ public:
 		void
 	UpdateBlenderObjectMatrix(Object* blendobj=NULL);
 
+	/**
+	 * Used for constraint replication for group instances.
+	 * The list of constraints is filled during data conversion.
+	 */
+	void AddConstraint(bRigidBodyJointConstraint *cons);
+	std::vector<bRigidBodyJointConstraint*> GetConstraints();
+	void ClearConstraints();
+
 	/** 
 	 * Get a pointer to the game object that is the parent of 
 	 * this object. Or NULL if there is no parent. The returned
diff --git a/source/gameengine/Ketsji/KX_Scene.cpp b/source/gameengine/Ketsji/KX_Scene.cpp
index d1b10098237..47510baa436 100644
--- a/source/gameengine/Ketsji/KX_Scene.cpp
+++ b/source/gameengine/Ketsji/KX_Scene.cpp
@@ -848,6 +848,12 @@ void KX_Scene::DupliGroupRecurse(CValue* obj, int level)
 	// now look if object in the hierarchy have dupli group and recurse
 	for (git = m_logicHierarchicalGameObjects.begin();!(git==m_logicHierarchicalGameObjects.end());++git)
 	{
+		/* Replicate all constraints. */
+		if ((*git)->GetPhysicsController()) {
+			(*git)->GetPhysicsController()->ReplicateConstraints((*git), m_logicHierarchicalGameObjects);
+			(*git)->ClearConstraints();
+		}
+
 		if ((*git) != groupobj && (*git)->IsDupliGroup())
 			// can't instantiate group immediately as it destroys m_logicHierarchicalGameObjects
 			duplilist.push_back((*git));