Abstract scene hierarchy node class. More...

#include <SceneHierarchyNode.h>

Inheritance diagram for PLScene::SceneHierarchyNode:

Public Member Functions
PLS_API SceneContext *	GetSceneContext () const
	Returns the scene context the scene hierarchy node is in.
PLS_API SceneHierarchy *	GetHierarchy () const
	Returns the owner scene hierarchy.
PLS_API SceneHierarchyNode *	GetParentNode () const
	Returns the parent scene hierarchy node.
PLS_API PLCore::uint32	GetID () const
	Returns the unique ID of the scene hierarchy node.
PLS_API PLCore::uint8	GetLevel () const
	Returns the level/tree depth of the scene hierarchy node.
PLS_API const PLMath::AABoundingBox &	GetAABoundingBox () const
	Returns the axis aligned bounding box of the scene hierarchy node.
PLS_API bool	CheckLine (const PLMath::Line &cLine) const
	Checks whether the scene hierarchy node volume is intersecting the given line.
PLS_API bool	CheckPlaneSet (const PLMath::PlaneSet &cPlaneSet, PLCore::uint32 *pnOutClipMask=nullptr) const
	Checks whether the scene hierarchy node volume is within the given plane set.
PLS_API char	GetPlaneSide (const PLMath::Plane &cPlane) const
	Returns the side of the plane the scene hierarchy node volume is on.
PLS_API float	GetShortestDistance (const PLMath::Vector3 &vPoint) const
	Returns the shortest distance from a given point to the scene hierarchy node volume.
PLS_API PLCore::uint32	GetNumOfItems () const
	Returns the number of scene hierarchy node items.
PLS_API SceneHierarchyNodeItem *	GetFirstItem () const
	Returns the first scene hierarchy node item.
virtual void	Touch (bool bRecursive=false)=0
	Touches the scene hierarchy scene node.
virtual PLCore::uint32	GetNumOfNodes () const =0
	Returns the number of child scene hierarchy nodes.
virtual SceneHierarchyNode *	GetNode (PLCore::uint32 nIndex) const =0
	Returns a child scene hierarchy node.
Protected Member Functions
PLS_API	SceneHierarchyNode (SceneHierarchy &cHierarchy)
	Constructor.
virtual PLS_API	~SceneHierarchyNode ()
	Destructor.
PLS_API SceneHierarchyNode &	GetFreeNode ()
	Returns a free scene hierarchy node.
PLS_API void	FreeNode (SceneHierarchyNode &cNode)
	Marks a scene hierarchy node as free.
virtual PLS_API void	Init ()
	Initializes the scene hierarchy node variables.
Protected Attributes
SceneHierarchy *	m_pHierarchy
SceneHierarchyNode *	m_pParentNode
PLCore::uint32	m_nID
PLCore::uint8	m_nLevel
PLMath::AABoundingBox	m_cAABoundingBox
PLCore::uint32	m_nNumOfItems
SceneHierarchyNodeItem *	m_pFirstItem

Detailed Description

Abstract scene hierarchy node class.

Remarks:: A scene hierarchy node can contain multiple scene hierarchy node items.

Constructor & Destructor Documentation

PLS_API PLScene::SceneHierarchyNode::SceneHierarchyNode ( SceneHierarchy & cHierarchy ) [protected]

Constructor.

Parameters:

[in] cHierarchy The owner hierarchy

virtual PLS_API PLScene::SceneHierarchyNode::~SceneHierarchyNode ( ) [protected, virtual]

Destructor.

Member Function Documentation

PLS_API SceneContext* PLScene::SceneHierarchyNode::GetSceneContext ( ) const

Returns the scene context the scene hierarchy node is in.

Returns:: The scene context the scene hierarchy node is in, can but shouldn't be a null pointer

PLS_API SceneHierarchy* PLScene::SceneHierarchyNode::GetHierarchy ( ) const

Returns the owner scene hierarchy.

Returns:: The owner scene hierarchy (NEVER a null pointer!)

PLS_API SceneHierarchyNode* PLScene::SceneHierarchyNode::GetParentNode ( ) const

Returns the parent scene hierarchy node.

Returns:: The parent scene hierarchy node, if a null pointer, this is the root

PLS_API PLCore::uint32 PLScene::SceneHierarchyNode::GetID ( ) const

Returns the unique ID of the scene hierarchy node.

Returns:: The unique ID of the scene hierarchy node

Remarks:: Some scene queries may need to hold some extra information per scene hierarchy node. In such cases, an unique node ID is quite useful to manage this information within for instance an array. SQCull for example may cache scene hierarchy node visibility information from the previous frame for the coherent hierarchical occlusion culling algorithm. In order to keep this unique node ID system working, ONLY SceneHierarchy::GetFreeNode() and SceneHierarchy::FreeNode() are used during runtime instead of new/delete. Have a look at the SceneHierarchy::GetFreeNode() documentation for more information about this.

PLS_API PLCore::uint8 PLScene::SceneHierarchyNode::GetLevel ( ) const

Returns the level/tree depth of the scene hierarchy node.

Returns:: The level/tree depth of the scene hierarchy node

PLS_API const PLMath::AABoundingBox& PLScene::SceneHierarchyNode::GetAABoundingBox ( ) const

Returns the axis aligned bounding box of the scene hierarchy node.

Returns:: The axis aligned bounding box of the scene hierarchy node

PLS_API bool PLScene::SceneHierarchyNode::CheckLine ( const PLMath::Line & cLine ) const

Checks whether the scene hierarchy node volume is intersecting the given line.

Parameters:

[in] cLine Line to check against

Returns:: 'false' if the scene hierarchy node volume is not intersecting the given line, else 'true'

PLS_API bool PLScene::SceneHierarchyNode::CheckPlaneSet	(	const PLMath::PlaneSet &	cPlaneSet,
		PLCore::uint32 *	pnOutClipMask = `nullptr`
	)		const

Checks whether the scene hierarchy node volume is within the given plane set.

Parameters:

[in]	cPlaneSet	Plane set to check against
[out]	pnOutClipMask	If not a null pointer, this clip mask will receive the intersection state of a maximum number of 32 planes if the box intersects the plane set.

Returns:: 'false' if the scene hierarchy node volume is not within the given plane set, else 'true'

PLS_API char PLScene::SceneHierarchyNode::GetPlaneSide ( const PLMath::Plane & cPlane ) const

Returns the side of the plane the scene hierarchy node volume is on.

Parameters:

[in] cPlane Plane to check against

Returns:: '-1' if of scene hierarchy node volume is behind the plane, '0' if it is intersecting the plane, '1' if the volume is in front of the plane

PLS_API float PLScene::SceneHierarchyNode::GetShortestDistance ( const PLMath::Vector3 & vPoint ) const

Returns the shortest distance from a given point to the scene hierarchy node volume.

Parameters:

[in] vPoint Point to get the shortest distance from

Returns:: Shortest distance (squared) from the given point to the scene hierarchy node volume

PLS_API PLCore::uint32 PLScene::SceneHierarchyNode::GetNumOfItems ( ) const

Returns the number of scene hierarchy node items.

Returns:: The number of scene hierarchy node items

PLS_API SceneHierarchyNodeItem* PLScene::SceneHierarchyNode::GetFirstItem ( ) const

Returns the first scene hierarchy node item.

Returns:: The first scene hierarchy node item, a null pointer if there are no items

Note:

Use SceneHierarchyNodeItem::GetPreviousItem()/SceneHierarchyNodeItem::GetNextItem() get the previous/next scene hierarchy node item

virtual void PLScene::SceneHierarchyNode::Touch ( bool bRecursive = false ) [pure virtual]

Touches the scene hierarchy scene node.

Parameters:

[in] bRecursive Touch recursive?

Remarks:: Scene node distribution (splitt/merge) within the scene hierarchy is only performed if this function is called. If during for instance a visibility determination a scene hierarchy node is used the first time during this process, one should call this 'touch' function to inform the scene hierarchy that this scene hierarchy node is going to be used. This function will split a scene hierarchy node if certain conditions like a maximum number of items per scene hierarchy node are given. If other conditions are given a merge operation is performed which 'combines' scene hierarchy nodes instead of splitting them. As result of this function, normally only the scene hierarchy parts which are currently used will be updated. ("lazy evaluation" :) If 'bRecursive' is set to true, all child nodes are touched to - but this may only be useful for instance when initializing the scene hierarchy.

Implemented in PLScene::SHKdTreeNode, and PLScene::SHListNode.

virtual PLCore::uint32 PLScene::SceneHierarchyNode::GetNumOfNodes ( ) const [pure virtual]

Returns the number of child scene hierarchy nodes.

Returns:: The number of child scene hierarchy nodes

Implemented in PLScene::SHKdTreeNode, and PLScene::SHListNode.

virtual SceneHierarchyNode* PLScene::SceneHierarchyNode::GetNode ( PLCore::uint32 nIndex ) const [pure virtual]

Returns a child scene hierarchy node.

Parameters:

[in] nIndex Index of the requested child scene hierarchy node

Returns:: The requested child scene hierarchy node, a null pointer on error

Implemented in PLScene::SHKdTreeNode, and PLScene::SHListNode.

PLS_API SceneHierarchyNode& PLScene::SceneHierarchyNode::GetFreeNode ( ) [protected]

Returns a free scene hierarchy node.

Returns:: Free scene hierarchy node

Remarks:: This function will return a free scene hierarchy node. If there are no free nodes available, a new one is created. After a node is no longer required it is put into the list of free nodes by using FreeNode() instead of destroying it. This way, frequently creation and destruction of nodes is avoided and the management of the unique node ID's becomes quite simple. See SceneHierarchyNode::GetID() for more information about the unique node ID's.

PLS_API void PLScene::SceneHierarchyNode::FreeNode ( SceneHierarchyNode & cNode ) [protected]

Marks a scene hierarchy node as free.

Parameters:

[in] cNode Scene hierarchy node to mark as free

See also: