blender/source/gameengine/Ketsji/KX_SG_NodeRelationships.h
Benoit Bolsee 51b4145841 BGE Scenegraph and View frustrum culling improvement.
This commit contains a number of performance improvements for the
BGE in the Scenegraph (parent relation between objects in the
scene) and view frustrum culling.

The scenegraph improvement consists in avoiding position update
if the object has not moved since last update and the removal
of redundant updates and synchronization with the physics engine.

The view frustrum culling improvement consists in using the DBVT
broadphase facility of Bullet to build a tree of graphical objects
in the scene. The elements of the tree are Aabb boxes (Aligned 
Axis Bounding Boxes) enclosing the objects. This provides good
precision in closed and opened scenes. This new culling system
is enabled by default but just in case, it can be disabled with
a button in the World settings. There is no do_version in this
commit but it will be added before the 2.49 release. For now you
must manually enable the DBVT culling option in World settings
when you open an old file.

The above improvements speed up scenegraph and culling up to 5x.
However, this performance improvement is only visible when
you have hundreds or thousands of objects.

The main interest of the DBVT tree is to allow easy occlusion
culling and automatic LOD system. This will be the object of further
improvements.
2009-04-07 22:14:06 +00:00

225 lines
3.8 KiB
C++

/**
* @mainpage KX_SG_NodeRelationships
* @section
*
* This file provides common concrete implementations of
* SG_ParentRelation used by the game engine. These are
* KX_SlowParentRelation a slow parent relationship.
* KX_NormalParentRelation a normal parent relationship where
* orientation and position are inherited from the parent by
* the child.
* KX_VertexParentRelation only location information is
* inherited by the child.
*
* interface
*
* $Id$
*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
* All rights reserved.
*
* The Original Code is: all of this file.
*
* Contributor(s): none yet.
*
* ***** END GPL LICENSE BLOCK *****
*
*/
#ifndef __KX_SG_NODERELATIONS_H__
#define __KX_SG_NODERELATIONS_H__
#include "SG_Spatial.h"
#include "SG_ParentRelation.h"
class KX_NormalParentRelation : public SG_ParentRelation
{
public :
/**
* Allocate and construct a new KX_NormalParentRelation
* on the heap.
*/
static
KX_NormalParentRelation *
New(
);
/**
* Method inherited from KX_ParentRelation
*/
bool
UpdateChildCoordinates(
SG_Spatial * child,
const SG_Spatial * parent,
bool& parentUpdated
);
/**
* Method inherited from KX_ParentRelation
*/
SG_ParentRelation *
NewCopy(
);
~KX_NormalParentRelation(
);
private :
KX_NormalParentRelation(
);
};
class KX_VertexParentRelation : public SG_ParentRelation
{
public :
/**
* Allocate and construct a new KX_VertexParentRelation
* on the heap.
*/
static
KX_VertexParentRelation *
New(
);
/**
* Method inherited from KX_ParentRelation
*/
bool
UpdateChildCoordinates(
SG_Spatial * child,
const SG_Spatial * parent,
bool& parentUpdated
);
/**
* Method inherited from KX_ParentRelation
*/
SG_ParentRelation *
NewCopy(
);
~KX_VertexParentRelation(
);
bool
IsVertexRelation(
) {
return true;
}
private :
KX_VertexParentRelation(
);
};
class KX_SlowParentRelation : public SG_ParentRelation
{
public :
/**
* Allocate and construct a new KX_VertexParentRelation
* on the heap.
*/
static
KX_SlowParentRelation *
New(
MT_Scalar relaxation
);
/**
* Method inherited from KX_ParentRelation
*/
bool
UpdateChildCoordinates(
SG_Spatial * child,
const SG_Spatial * parent,
bool& parentUpdated
);
/**
* Method inherited from KX_ParentRelation
*/
SG_ParentRelation *
NewCopy(
);
MT_Scalar
GetTimeOffset(
) { return m_relax; }
void
SetTimeOffset(
MT_Scalar relaxation
) { m_relax = relaxation; }
~KX_SlowParentRelation(
);
bool
IsSlowRelation(
) {
return true;
}
private :
KX_SlowParentRelation(
MT_Scalar relaxation
);
// the relaxation coefficient.
MT_Scalar m_relax;
/**
* Looks like a hack flag to me.
* We need to compute valid world coordinates the first
* time we update spatial data of the child. This is done
* by just doing a normal parent relation the first time
* UpdateChildCoordinates is called and then doing the
* slow parent relation
*/
bool m_initialized;
};
#endif