Ogre::SceneQuery Class Reference

A class for performing queries on a scene. More...

#include <OgreSceneQuery.h>

Inheritance diagram for Ogre::SceneQuery:

Classes
struct	WorldFragment
	Represents part of the world geometry that is a result of a SceneQuery. More...

Public Types
enum	WorldFragmentType {   WFT_NONE , WFT_PLANE_BOUNDED_REGION , WFT_SINGLE_INTERSECTION , WFT_CUSTOM_GEOMETRY ,   WFT_RENDER_OPERATION }
	This type can be used by collaborating applications & SceneManagers to agree on the type of world geometry to be returned from queries. More...

Public Member Functions
	SceneQuery (SceneManager *mgr)
	Standard constructor, should be called by SceneManager. More...
virtual	~SceneQuery ()
virtual uint32	getQueryMask () const
	Returns the current mask for this query. More...
virtual const set< WorldFragmentType >::type *	getSupportedWorldFragmentTypes () const
	Returns the types of world fragments this query supports. More...
virtual WorldFragmentType	getWorldFragmentType () const
	Gets the current world fragment types to be returned from the query. More...
virtual void	setQueryMask (uint32 mask)
	Sets the mask for results of this query. More...
virtual void	setWorldFragmentType (enum WorldFragmentType wft)
	Tells the query what kind of world geometry to return from queries; often the full renderable geometry is not what is needed. More...

Public Attributes
uint8	mFirstRq
uint8	mLastRq

Detailed Description

A class for performing queries on a scene.

Remarks

This is an abstract class for performing a query on a scene, i.e. to retrieve a list of objects and/or world geometry sections which are potentially intersecting a given region. Note the use of the word 'potentially': the results of a scene query are generated based on bounding volumes, and as such are not correct at a triangle level; the user of the SceneQuery is expected to filter the results further if greater accuracy is required.

Different SceneManagers will implement these queries in different ways to exploit their particular scene organisation, and thus will provide their own concrete subclasses. In fact, these subclasses will be derived from subclasses of this class rather than directly because there will be region-type classes in between.

These queries could have just been implemented as methods on the SceneManager, however, they are wrapped up as objects to allow 'compilation' of queries if deemed appropriate by the implementation; i.e. each concrete subclass may precalculate information (such as fixed scene partitions involved in the query) to speed up the repeated use of the query.

You should never try to create a SceneQuery object yourself, they should be created using the SceneManager interfaces for the type of query required, e.g. SceneManager::createSphereSceneQuery.

Member Enumeration Documentation

WorldFragmentType

enum Ogre::SceneQuery::WorldFragmentType

This type can be used by collaborating applications & SceneManagers to agree on the type of world geometry to be returned from queries.

Not all these types will be supported by all SceneManagers; once the application has decided which SceneManager specialisation to use, it is expected that it will know which type of world geometry abstraction is available to it.

Enumerator
WFT_NONE	Return no world geometry hits at all.
WFT_PLANE_BOUNDED_REGION	Return pointers to convex plane-bounded regions.
WFT_SINGLE_INTERSECTION	Return a single intersection point (typically RaySceneQuery only)
WFT_CUSTOM_GEOMETRY	Custom geometry as defined by the SceneManager.
WFT_RENDER_OPERATION	General RenderOperation structure.

Constructor & Destructor Documentation

SceneQuery()

Ogre::SceneQuery::SceneQuery

(

SceneManager *

mgr

)

Standard constructor, should be called by SceneManager.

~SceneQuery()

virtual Ogre::SceneQuery::~SceneQuery ( )

virtual

Member Function Documentation

getQueryMask()

virtual uint32 Ogre::SceneQuery::getQueryMask ( ) const

virtual

Returns the current mask for this query.

getSupportedWorldFragmentTypes()

virtual const set<WorldFragmentType>::type* Ogre::SceneQuery::getSupportedWorldFragmentTypes ( ) const

inlinevirtual

Returns the types of world fragments this query supports.

getWorldFragmentType()

virtual WorldFragmentType Ogre::SceneQuery::getWorldFragmentType ( ) const

virtual

Gets the current world fragment types to be returned from the query.

setQueryMask()

virtual void Ogre::SceneQuery::setQueryMask ( uint32  mask )

virtual

Sets the mask for results of this query.

Remarks

This method allows you to set a 'mask' to limit the results of this query to certain types of result. The actual meaning of this value is up to the application; basically MovableObject instances will only be returned from this query if a bitwise AND operation between this mask value and the MovableObject::getQueryFlags value is non-zero. The application will have to decide what each of the bits means. The default initial query mask of a SceneQuery is SceneManager::QUERY_ENTITY_DEFAULT_MASK

Note

By default, Ogre uses SceneManager::QUERY_ENTITY_DEFAULT_MASK and Co. to set each type of MovableObject's default query mask. This behavior can be overriden though, just set the masks you don't need to 0 before creating those objects.

setWorldFragmentType()

virtual void Ogre::SceneQuery::setWorldFragmentType ( enum WorldFragmentType  wft )

virtual

Tells the query what kind of world geometry to return from queries; often the full renderable geometry is not what is needed.

Remarks

The application receiving the world geometry is expected to know what to do with it; inevitably this means that the application must have knowledge of at least some of the structures used by the custom SceneManager.

The default setting is WFT_NONE.

Member Data Documentation

mFirstRq

uint8 Ogre::SceneQuery::mFirstRq

mLastRq

uint8 Ogre::SceneQuery::mLastRq

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The documentation for this class was generated from the following file:

• OgreSceneQuery.h