Patch: [ #2439 ] Makes objects react properly to deformations after a mesh replacement call.

from brian hayward (bthayward)

Detailed description:
 Currently, when an armature deformed object's mesh is replaced by the ReplaceMesh actuator, the new mesh fails to deform to the armature's movement.

 My patch fixes this by properly replacing the deform controller along with the mesh (when appropriete).

 For instance, if one had an animated character using any of the standard deformation techniques (armature, ipo, RVK, or AVK), that character's mesh would currently be prevented from changing mid-game. It could be replaced, but the new mesh would lack the controller which tells it how to deform. If one wanted to dynamiclly add a hat on top of the character's head, it would require storing a secondary prebuilt character (mesh, armature, logic, ect...) on another layer FOR EACH HAT the character could possibly wear, then swapping out the whole character when the hat change was desired. So if you had 4 possible hat/character combos, you would have 4 character meshes, 4 armatures, 4 sets of logic, and so on. I find this lack of flexibility to be unresonable.

 With my patch, one could accomplish the same thing mearly by making one version of the character in the main layer, and adding an invisible object atop the character's head (which is parented to the head bone). Then whenever it becomes desirable, one can replace the invisible object's mesh with the desirable hat's mesh, then make it visible. With my patch, the hat object would then continue to deform to the character's head regardless of which hat was currently being worn.

 *note 1*
 for armature/mesh deformations, the new mesh must have properly assigned vertex groups which match one or more of the bones of the target armature before the replaceMesh call is made. Otherwise the vertices won't react to the armature because they won't know how. (not sure if vertices can be scripted to change groups after the game has started)

 *note 2*
 The added processing time involved with replacing the object's deform controller is negligible.

source/gameengine/Converter/BL_BlenderDataConversion.cpp

@@ -1170,6 +1170,11 @@ void BL_ConvertBlenderObjects(struct Main* maggie,
 			
 			// needed for python scripting
 			logicmgr->RegisterGameObjectName(gameobj->GetName(),gameobj);
+
+			// needed for dynamic object morphing
+			logicmgr->RegisterGameObj(gameobj, blenderobject);
+			for (int i = 0; i < gameobj->GetMeshCount(); i++)
+				logicmgr->RegisterGameMeshName(gameobj->GetMesh(i)->GetName(), blenderobject);
 	
 			converter->RegisterGameObject(gameobj, blenderobject);	
 			

source/gameengine/Converter/BL_DeformableGameObject.h

@@ -56,8 +56,9 @@ public:
 	BL_DeformableGameObject(void* sgReplicationInfo, SG_Callbacks callbacks) :
 		KX_GameObject(sgReplicationInfo,callbacks),
 		m_pDeformer(NULL)
-{
-	  };
+	{
+		m_isDeformable = true;
+	};
 	virtual ~BL_DeformableGameObject();
 
 };

source/gameengine/Converter/BL_SkinDeformer.h

@@ -79,7 +79,21 @@ public:
 		for (bDeformGroup *dg=(bDeformGroup*)m_defbase->first; dg; dg=(bDeformGroup*)dg->next)
 			dg->data = (void*)get_named_bone(barm, dg->name);
 */
-	};	
+	};
+
+	/* this second constructor is needed for making a mesh deformable on the fly. */
+
+	BL_SkinDeformer(	struct Object *bmeshobj_old,
+						struct Object *bmeshobj_new,
+						class BL_SkinMeshObject *mesh)
+						:BL_MeshDeformer(bmeshobj_old, mesh),
+						m_armobj(NULL),
+						m_lastUpdate(-1),
+						m_defbase(&bmeshobj_old->defbase)
+	{
+		GB_build_mats(bmeshobj_new->parent->obmat, bmeshobj_new->obmat, m_premat, m_postmat);
+		GB_validate_defgroups((Mesh*)bmeshobj_old->data, m_defbase);
+	};
 
 	virtual void ProcessReplica();
 	virtual RAS_Deformer *GetReplica();

source/gameengine/GameLogic/SCA_LogicManager.cpp

@@ -116,6 +116,21 @@ void SCA_LogicManager::RegisterGameObjectName(const STR_String& gameobjname,
 
 
 
+void SCA_LogicManager::RegisterGameMeshName(const STR_String& gamemeshname, void* blendobj)
+{
+	STR_HashedString mn = gamemeshname;
+	m_map_gamemeshname_to_blendobj.insert(mn, blendobj);
+}
+
+
+
+void SCA_LogicManager::RegisterGameObj(CValue* gameobj, void* blendobj) 
+{
+	m_map_gameobj_to_blendobj.insert(CHashedPtr(gameobj), blendobj);
+}
+
+
+
 CValue* SCA_LogicManager::GetGameObjectByName(const STR_String& gameobjname)
 {
 	STR_HashedString mn = "OB"+gameobjname;
@@ -128,6 +143,22 @@ CValue* SCA_LogicManager::GetGameObjectByName(const STR_String& gameobjname)
 }
 
 
+void* SCA_LogicManager::FindBlendObjByGameObj(CValue* gameobject) 
+{
+	void **obp= m_map_gameobj_to_blendobj[CHashedPtr(gameobject)];
+	return obp?*obp:NULL;
+}
+
+
+
+void* SCA_LogicManager::FindBlendObjByGameMeshName(const STR_String& gamemeshname) 
+{
+	STR_HashedString mn = gamemeshname;
+	void **obp= m_map_gamemeshname_to_blendobj[mn];
+	return obp?*obp:NULL;
+}
+
+
 
 void SCA_LogicManager::RemoveSensor(SCA_ISensor* sensor)
 {

source/gameengine/GameLogic/SCA_LogicManager.h

@@ -47,6 +47,8 @@
 #include "STR_HashedString.h"
 #include "Value.h"
 
+#include "KX_HashedPtr.h"
+
 using namespace std;
 typedef list<class SCA_IController*> controllerlist;
 
@@ -111,6 +113,9 @@ class SCA_LogicManager
 	GEN_Map<STR_HashedString,void*>		m_mapStringToMeshes;
 	GEN_Map<STR_HashedString,void*>		m_mapStringToActions;
 
+	GEN_Map<STR_HashedString,void*>		m_map_gamemeshname_to_blendobj;
+	GEN_Map<CHashedPtr,void*>			m_map_gameobj_to_blendobj;
+
 	vector<SmartActuatorPtr>			m_removedActuators;
 
 public:
@@ -149,6 +154,12 @@ public:
 
 	void	RegisterGameObjectName(const STR_String& gameobjname,CValue* gameobj);
 	class CValue*	GetGameObjectByName(const STR_String& gameobjname);
+
+	void	RegisterGameMeshName(const STR_String& gamemeshname, void* blendobj);
+	void*	FindBlendObjByGameMeshName(const STR_String& gamemeshname);
+
+	void	RegisterGameObj(CValue* gameobj, void* blendobj);
+	void*	FindBlendObjByGameObj(CValue* gameobj);
 };
 
 #endif //__KX_LOGICMANAGER

source/gameengine/Ketsji/KX_GameObject.cpp

@@ -72,7 +72,8 @@ KX_GameObject::KX_GameObject(
 	m_bSuspendDynamics(false),
 	m_bUseObjectColor(false),
 	m_bVisible(true),
-	m_pPhysicsController1(NULL)
+	m_pPhysicsController1(NULL),
+	m_isDeformable(false)
 {
 	m_ignore_activity_culling = false;
 	m_pClient_info = new KX_ClientObjectInfo(this, KX_ClientObjectInfo::ACTOR);

source/gameengine/Ketsji/KX_GameObject.h

@@ -87,6 +87,8 @@ protected:
 	MT_CmMatrix4x4						m_OpenGL_4x4Matrix;
 	
 public:
+	bool								m_isDeformable;
+
 	virtual void	/* This function should be virtual - derived classed override it */
 	Relink(
 		GEN_Map<GEN_HashedPtr, void*> *map

source/gameengine/Ketsji/KX_Scene.cpp

@@ -73,6 +73,9 @@
 #include "PHY_IPhysicsEnvironment.h"
 #include "KX_IPhysicsController.h"
 
+#include "BL_SkinDeformer.h"
+#include "BL_DeformableGameObject.h"
+
 
 void* KX_SceneReplicationFunc(SG_IObject* node,void* gameobj,void* scene)
 {
@@ -719,8 +722,33 @@ void KX_Scene::NewRemoveObject(class CValue* gameobj)
 void KX_Scene::ReplaceMesh(class CValue* gameobj,void* meshobj)
 {
 	KX_GameObject* newobj = (KX_GameObject*) gameobj;
+	RAS_MeshObject* mesh = (RAS_MeshObject*) meshobj;
+
 	newobj->RemoveMeshes();
-	newobj->AddMesh((RAS_MeshObject*)meshobj);
+	newobj->AddMesh(mesh);
+
+	if (newobj->m_isDeformable && mesh->m_class == 1) {
+		Object* blendobj = (struct Object*)m_logicmgr->FindBlendObjByGameObj(newobj);
+		Object* oldblendobj = (struct Object*)m_logicmgr->FindBlendObjByGameMeshName(mesh->GetName());
+		if (blendobj->parent && blendobj->parent->type == OB_ARMATURE && blendobj->partype==PARSKEL && ((Mesh*)blendobj->data)->dvert) {
+			BL_SkinDeformer* skindeformer = new BL_SkinDeformer(oldblendobj, blendobj, (BL_SkinMeshObject*)mesh);
+			skindeformer->SetArmature((BL_ArmatureObject*) newobj->GetParent());
+			
+			// FIXME: should the old m_pDeformer be deleted?
+			// delete ((BL_DeformableGameObject*)newobj)->m_pDeformer
+			
+			((BL_DeformableGameObject*)newobj)->m_pDeformer = skindeformer;
+		}
+		else if (((Mesh*)blendobj->data)->dvert) {
+			BL_MeshDeformer* meshdeformer = new BL_MeshDeformer(oldblendobj, (BL_SkinMeshObject*)mesh);
+			
+			// FIXME: should the old m_pDeformer be deleted?
+			// delete ((BL_DeformableGameObject*)newobj)->m_pDeformer
+			
+			((BL_DeformableGameObject*)newobj)->m_pDeformer = meshdeformer;
+		}
+	}
+
 	newobj->Bucketize();
 }