Ogre::ShadowCaster Class Reference

This class defines the interface that must be implemented by shadow casters. More...

#include <OgreShadowCaster.h>

Inheritance diagram for Ogre::ShadowCaster:

Public Types
typedef std::vector< ShadowRenderable * >	ShadowRenderableList
typedef VectorIterator< ShadowRenderableList >	ShadowRenderableListIterator

Public Member Functions
virtual	~ShadowCaster ()
virtual bool	getCastShadows (void) const =0
	Returns whether or not this object currently casts a shadow. More...
virtual const AxisAlignedBox &	getDarkCapBounds (const Light &light, Real dirLightExtrusionDist) const =0
	Gets the world space bounding box of the dark cap, as extruded using the light provided. More...
virtual EdgeData *	getEdgeList (void)=0
	Returns details of the edges which might be used to determine a silhouette. More...
virtual const AxisAlignedBox &	getLightCapBounds (void) const =0
	Gets the world space bounding box of the light cap. More...
virtual Real	getPointExtrusionDistance (const Light *l) const =0
	Get the distance to extrude for a point/spot light. More...
virtual ShadowRenderableListIterator	getShadowVolumeRenderableIterator (ShadowTechnique shadowTechnique, const Light *light, HardwareIndexBufferSharedPtr *indexBuffer, size_t *indexBufferUsedSize, bool extrudeVertices, Real extrusionDistance, unsigned long flags=0)=0
	Gets an iterator over the renderables required to render the shadow volume. More...
virtual const AxisAlignedBox &	getWorldBoundingBox (bool derive=false) const =0
	Get the world bounding box of the caster. More...
virtual bool	hasEdgeList (void)=0
	Returns whether the object has a valid edge list. More...

Static Public Member Functions
static void	clearShadowRenderableList (ShadowRenderableList &shadowRenderables)
	Common implementation of releasing shadow renderables. More...
static void	extrudeVertices (const HardwareVertexBufferSharedPtr &vertexBuffer, size_t originalVertexCount, const Vector4 &lightPos, Real extrudeDist)
	Utility method for extruding vertices based on a light. More...

Detailed Description

This class defines the interface that must be implemented by shadow casters.

Member Typedef Documentation

ShadowRenderableList

typedef std::vector<ShadowRenderable*> Ogre::ShadowCaster::ShadowRenderableList

ShadowRenderableListIterator

typedef VectorIterator<ShadowRenderableList> Ogre::ShadowCaster::ShadowRenderableListIterator

Constructor & Destructor Documentation

~ShadowCaster()

virtual Ogre::ShadowCaster::~ShadowCaster ( )

inlinevirtual

Member Function Documentation

getCastShadows()

virtual bool Ogre::ShadowCaster::getCastShadows ( void  ) const

pure virtual

Returns whether or not this object currently casts a shadow.

Implemented in Ogre::MovableObject.

getEdgeList()

virtual EdgeData* Ogre::ShadowCaster::getEdgeList ( void  )

pure virtual

Returns details of the edges which might be used to determine a silhouette.

Implemented in Ogre::Entity, Ogre::MovableObject, Ogre::StaticGeometry::Region, and Ogre::ManualObject.

hasEdgeList()

virtual bool Ogre::ShadowCaster::hasEdgeList ( void  )

pure virtual

Returns whether the object has a valid edge list.

Implemented in Ogre::Entity, Ogre::MovableObject, Ogre::StaticGeometry::Region, and Ogre::ManualObject.

getWorldBoundingBox()

virtual const AxisAlignedBox& Ogre::ShadowCaster::getWorldBoundingBox ( bool  derive = false ) const

pure virtual

Get the world bounding box of the caster.

Implemented in Ogre::Entity, Ogre::MovableObject, and Ogre::PortalBase.

getLightCapBounds()

virtual const AxisAlignedBox& Ogre::ShadowCaster::getLightCapBounds ( void  ) const

pure virtual

Gets the world space bounding box of the light cap.

Implemented in Ogre::MovableObject.

getDarkCapBounds()

virtual const AxisAlignedBox& Ogre::ShadowCaster::getDarkCapBounds ( const Light &  light, Real  dirLightExtrusionDist  ) const

pure virtual

Gets the world space bounding box of the dark cap, as extruded using the light provided.

Implemented in Ogre::MovableObject.

getShadowVolumeRenderableIterator()

virtual ShadowRenderableListIterator Ogre::ShadowCaster::getShadowVolumeRenderableIterator ( ShadowTechnique  shadowTechnique, const Light *  light, HardwareIndexBufferSharedPtr *  indexBuffer, size_t *  indexBufferUsedSize, bool  extrudeVertices, Real  extrusionDistance, unsigned long  flags = 0  )

pure virtual

Gets an iterator over the renderables required to render the shadow volume.

Remarks

Shadowable geometry should ideally be designed such that there is only one ShadowRenderable required to render the the shadow; however this is not a necessary limitation and it can be exceeded if required.

Parameters

shadowTechnique	The technique being used to generate the shadow.
light	The light to generate the shadow from.
indexBuffer	The index buffer to build the renderables into, the current contents are assumed to be disposable.
extrudeVertices	If true, this means this class should extrude the vertices of the back of the volume in software. If false, it will not be done (a vertex program is assumed).
extrusionDistance	The distance to extrude the shadow volume.
flags	Technique-specific flags, see ShadowRenderableFlags.

Implemented in Ogre::Entity, Ogre::MovableObject, Ogre::StaticGeometry::Region, and Ogre::ManualObject.

clearShadowRenderableList()

static void Ogre::ShadowCaster::clearShadowRenderableList ( ShadowRenderableList &  shadowRenderables )

static

Common implementation of releasing shadow renderables.

extrudeVertices()

static void Ogre::ShadowCaster::extrudeVertices ( const HardwareVertexBufferSharedPtr &  vertexBuffer, size_t  originalVertexCount, const Vector4 &  lightPos, Real  extrudeDist  )

static

Utility method for extruding vertices based on a light.

Remarks

Unfortunately, because D3D cannot handle homogeneous (4D) position coordinates in the fixed-function pipeline (GL can, but we have to be cross-API), when we extrude in software we cannot extrude to infinity the way we do in the vertex program (by setting w to 0.0f). Therefore we extrude by a fixed distance, which may cause some problems with larger scenes. Luckily better hardware (ie vertex programs) can fix this.

Parameters

vertexBuffer	The vertex buffer containing ONLY xyz position values, which must be originalVertexCount * 2 * 3 floats long.
originalVertexCount	The count of the original number of vertices, i.e. the number in the mesh, not counting the doubling which has already been done (by VertexData::prepareForShadowVolume) to provide the extruded area of the buffer.
lightPos	4D light position in object space, when w=0.0f this represents a directional light.
extrudeDist	The distance to extrude.

getPointExtrusionDistance()

virtual Real Ogre::ShadowCaster::getPointExtrusionDistance ( const Light *  l ) const

pure virtual

Get the distance to extrude for a point/spot light.

Implemented in Ogre::MovableObject.

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

• OgreShadowCaster.h