Implements the uniform shadow mapping algorithm in focused mode. More...

#include <OgreShadowCameraSetupFocused.h>

Inheritance diagram for Ogre::FocusedShadowCameraSetup:

Classes
class	PointListBody
	Internal class holding a point list representation of a convex body. More...
Public Member Functions
	FocusedShadowCameraSetup (void)
	Default constructor.
virtual	~FocusedShadowCameraSetup (void)
	Default destructor.
virtual void	getShadowCamera (const SceneManager sm, const Camera cam, const Viewport vp, const Light light, Camera *texCam, size_t iteration) const
	Returns a uniform shadow camera with a focused view.
bool	getUseAggressiveFocusRegion () const
void	operator delete (void *ptr)
void	operator delete (void ptr, void )
void	operator delete (void ptr, const char , int, const char *)
void	operator delete[] (void *ptr)
void	operator delete[] (void ptr, const char , int, const char *)
void *	operator new (size_t sz, const char file, int line, const char func)
	operator new, with debug line info
void *	operator new (size_t sz)
void *	operator new (size_t sz, void *ptr)
	placement operator new
void *	operator new[] (size_t sz, const char file, int line, const char func)
	array operator new, with debug line info
void *	operator new[] (size_t sz)
void	setUseAggressiveFocusRegion (bool aggressive)
	Sets whether or not to use the more aggressive approach to deciding on the focus region or not.
Protected Member Functions
Matrix4	buildViewMatrix (const Vector3 &pos, const Vector3 &dir, const Vector3 &up) const
	Builds a view matrix.
void	calculateB (const SceneManager &sm, const Camera &cam, const Light &light, const AxisAlignedBox &sceneBB, const AxisAlignedBox &receiverBB, PointListBody *out_bodyB) const
	Calculates the intersection bodyB.
void	calculateLVS (const SceneManager &sm, const Camera &cam, const Light &light, const AxisAlignedBox &sceneBB, PointListBody *out_LVS) const
	Calculates the bodyLVS.
void	calculateShadowMappingMatrix (const SceneManager &sm, const Camera &cam, const Light &light, Matrix4 out_view, Matrix4 out_proj, Camera *out_cam) const
	Calculates the standard shadow mapping matrix.
Vector3	getLSProjViewDir (const Matrix4 &lightSpace, const Camera &cam, const PointListBody &bodyLVS) const
	Returns the projection view direction.
Vector3	getNearCameraPoint_ws (const Matrix4 &viewMatrix, const PointListBody &bodyLVS) const
	Returns a valid near-point seen by the camera.
Matrix4	transformToUnitCube (const Matrix4 &m, const PointListBody &body) const
	Transforms a given body to the unit cube (-1,-1,-1) / (+1,+1,+1) with a specific shadow matrix enabled.
Protected Attributes
ConvexBody	mBodyB
Camera *	mLightFrustumCamera
	Temporary preallocated camera to set up a light frustum for clipping in FocusedShadowCameraSetup::calculateB.
bool	mLightFrustumCameraCalculated
PointListBody	mPointListBodyB
PointListBody	mPointListBodyLVS
Frustum *	mTempFrustum
	Temporary preallocated frustum to set up a projection matrix in calculateShadowMappingMatrix().
bool	mUseAggressiveRegion
	Use tighter focus region?
Static Protected Attributes
static const Matrix4	msLightSpaceToNormal
static const Matrix4	msNormalToLightSpace
	Transform to or from light space as defined by Wimmer et al.

Detailed Description

Implements the uniform shadow mapping algorithm in focused mode.

Remarks:: Differs from the default shadow mapping projection in that it focuses the shadow map on the visible areas of the scene. This results in better shadow map texel usage, at the expense of some 'swimming' of the shadow texture on receivers as the basis is constantly being reevaluated.

Note:: Original implementation by Matthias Fink <matthias.fink@web.de>, 2006.

Definition at line 58 of file OgreShadowCameraSetupFocused.h.

Constructor & Destructor Documentation

Ogre::FocusedShadowCameraSetup::FocusedShadowCameraSetup ( void )

Default constructor.

Remarks:: Temporary frustum and camera set up here.

virtual Ogre::FocusedShadowCameraSetup::~FocusedShadowCameraSetup ( void ) [virtual]

Default destructor.

Remarks:: Temporary frustum and camera destroyed here.

Member Function Documentation

Matrix4 Ogre::FocusedShadowCameraSetup::buildViewMatrix	(	const Vector3 &	pos,
		const Vector3 &	dir,
		const Vector3 &	up
	)		const `[protected]`

Builds a view matrix.

Remarks:: Builds a standard view matrix out of a given position, direction and up vector.

void Ogre::FocusedShadowCameraSetup::calculateB	(	const SceneManager &	sm,
		const Camera &	cam,
		const Light &	light,
		const AxisAlignedBox &	sceneBB,
		const AxisAlignedBox &	receiverBB,
		PointListBody *	out_bodyB
	)		const `[protected]`

Calculates the intersection bodyB.

Remarks:: The intersection bodyB consists of the concatenation the cam frustum clipped by the scene bounding box followed by a convex hullification with the light's position and the clipping with the scene bounding box and the light frustum: ((V S) + l) S L (: convex intersection, +: convex hull operation). For directional lights the bodyB is assembled out of the camera frustum clipped by the scene bounding box followed by the extrusion of all available bodyB points towards the negative light direction. The rays are intersected by a maximum bounding box and added to the bodyB points to form the final intersection bodyB point list.

Parameters:

sm	Scene manager.
cam	Currently active camera.
light	Currently active light.
sceneBB	Scene bounding box for clipping operations.
receiverBB	Bounding information for just the receivers.
out_bodyB	Final intersection bodyB point list.

void Ogre::FocusedShadowCameraSetup::calculateLVS	(	const SceneManager &	sm,
		const Camera &	cam,
		const Light &	light,
		const AxisAlignedBox &	sceneBB,
		PointListBody *	out_LVS
	)		const `[protected]`

Calculates the bodyLVS.

Remarks:: Calculates the bodyLVS which consists of the convex intersection operation affecting the light frustum, the view frustum, and the current scene bounding box is used to find suitable positions in the viewer's frustum to build the rotation matrix L_r. This matrix is applied after the projection matrix L_p to avoid an accidental flip of the frustum orientation for views tilted with respect to the shadow map.

Parameters:

cam	Current viewer camera.
light	Current light.
sceneBB	Holds all potential occluders / receivers as one single bounding box of the currently active scene node.
out_LVS	Intersection body LVS (world coordinates).

void Ogre::FocusedShadowCameraSetup::calculateShadowMappingMatrix	(	const SceneManager &	sm,
		const Camera &	cam,
		const Light &	light,
		Matrix4 *	out_view,
		Matrix4 *	out_proj,
		Camera *	out_cam
	)		const `[protected]`

Calculates the standard shadow mapping matrix.

Remarks:: Provides the view and projection matrix for standard shadow mapping.

Note:: You can choose which things you want to have: view matrix and/or projection matrix and/or shadow camera. Passing a NULL value as parameter ignores the generation of this specific value.

Parameters:

sm	Scene manager.
cam	Currently active camera.
light	Currently active light.
out_view	Calculated uniform view shadow mapping matrix (may be `NULL`).
out_proj	Calculated uniform projection shadow mapping matrix (may be `NULL`).
out_cam	Calculated uniform shadow camera (may be `NULL`).

Vector3 Ogre::FocusedShadowCameraSetup::getLSProjViewDir	(	const Matrix4 &	lightSpace,
		const Camera &	cam,
		const PointListBody &	bodyLVS
	)		const `[protected]`

Returns the projection view direction.

Remarks:: After the matrix L_p is applied the orientation of the light space may tilt for non-identity projections. To prevent a false shadow cast the real view direction is evaluated and applied to the light matrix L.

Parameters:

lightSpace	Matrix of the light space transformation.
cam	Current viewer camera.
bodyLVS	Intersection body LVS (relevant space in front of the camera).

Vector3 Ogre::FocusedShadowCameraSetup::getNearCameraPoint_ws	(	const Matrix4 &	viewMatrix,
		const PointListBody &	bodyLVS
	)		const `[protected]`

Returns a valid near-point seen by the camera.

Remarks:: Returns a point that is situated near the camera by analyzing the bodyLVS that contains all the relevant scene space in front of the light and the camera in a point list array. The view matrix is relevant because the nearest point in front of the camera should be determined.

Parameters:

viewMatrix	View matrix of the current camera.
bodyLVS	Intersection body LVS (relevant space in front of the camera).

virtual void Ogre::FocusedShadowCameraSetup::getShadowCamera	(	const SceneManager *	sm,
		const Camera *	cam,
		const Viewport *	vp,
		const Light *	light,
		Camera *	texCam,
		size_t	iteration
	)		const `[virtual]`

Returns a uniform shadow camera with a focused view.

Implements Ogre::ShadowCameraSetup.

Reimplemented in Ogre::LiSPSMShadowCameraSetup, and Ogre::PSSMShadowCameraSetup.

bool Ogre::FocusedShadowCameraSetup::getUseAggressiveFocusRegion ( ) const

Definition at line 305 of file OgreShadowCameraSetupFocused.h.

template<class Alloc >

void Ogre::AllocatedObject< Alloc >::operator delete ( void * ptr ) [inherited]

Definition at line 96 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void Ogre::AllocatedObject< Alloc >::operator delete	(	void *	ptr,
		void *
	)		`[inherited]`

Definition at line 102 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void Ogre::AllocatedObject< Alloc >::operator delete	(	void *	ptr,
		const char *	,
		int	,
		const char *
	)		`[inherited]`

Definition at line 108 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void Ogre::AllocatedObject< Alloc >::operator delete[] ( void * ptr ) [inherited]

Definition at line 113 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void Ogre::AllocatedObject< Alloc >::operator delete[]	(	void *	ptr,
		const char *	,
		int	,
		const char *
	)		`[inherited]`

Definition at line 119 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void* Ogre::AllocatedObject< Alloc >::operator new	(	size_t	sz,
		const char *	file,
		int	line,
		const char *	func
	)		`[inherited]`

operator new, with debug line info

Definition at line 68 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void* Ogre::AllocatedObject< Alloc >::operator new ( size_t sz ) [inherited]

Definition at line 73 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void* Ogre::AllocatedObject< Alloc >::operator new	(	size_t	sz,
		void *	ptr
	)		`[inherited]`

placement operator new

Definition at line 79 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void* Ogre::AllocatedObject< Alloc >::operator new[]	(	size_t	sz,
		const char *	file,
		int	line,
		const char *	func
	)		`[inherited]`

array operator new, with debug line info

Definition at line 86 of file OgreMemoryAllocatedObject.h.

template<class Alloc >

void* Ogre::AllocatedObject< Alloc >::operator new[] ( size_t sz ) [inherited]

Definition at line 91 of file OgreMemoryAllocatedObject.h.

void Ogre::FocusedShadowCameraSetup::setUseAggressiveFocusRegion ( bool aggressive )

Sets whether or not to use the more aggressive approach to deciding on the focus region or not.

Note:: There are 2 approaches that can be used to define the focus region, the more aggressive way introduced by Wimmer et al, or the original way as described in Stamminger et al. Wimmer et al's way tends to come up with a tighter focus region but in rare cases (mostly highly glancing angles) can cause some shadow casters to be clipped incorrectly. By default the more aggressive approach is used since it leads to significantly better results in most cases, but if you experience clipping issues, you can use the less aggressive version.

Parameters:

aggressive True to use the more aggressive approach, false otherwise.

Definition at line 303 of file OgreShadowCameraSetupFocused.h.

Matrix4 Ogre::FocusedShadowCameraSetup::transformToUnitCube	(	const Matrix4 &	m,
		const PointListBody &	body
	)		const `[protected]`

Transforms a given body to the unit cube (-1,-1,-1) / (+1,+1,+1) with a specific shadow matrix enabled.

Remarks:: Transforms a given point list body object with the matrix m and then maps its extends to a (-1,-1,-1) / (+1,+1,+1) unit cube.

Parameters:

m	Transformation matrix applied on the point list body.
body	Contains the points of the extends of all valid scene elements which are mapped to the unit cube.

Member Data Documentation

ConvexBody Ogre::FocusedShadowCameraSetup::mBodyB [mutable, protected]

Definition at line 145 of file OgreShadowCameraSetupFocused.h.

Camera* Ogre::FocusedShadowCameraSetup::mLightFrustumCamera [protected]

Temporary preallocated camera to set up a light frustum for clipping in FocusedShadowCameraSetup::calculateB.

Definition at line 78 of file OgreShadowCameraSetupFocused.h.

bool Ogre::FocusedShadowCameraSetup::mLightFrustumCameraCalculated [mutable, protected]

Definition at line 79 of file OgreShadowCameraSetupFocused.h.

PointListBody Ogre::FocusedShadowCameraSetup::mPointListBodyB [mutable, protected]

Definition at line 146 of file OgreShadowCameraSetupFocused.h.

PointListBody Ogre::FocusedShadowCameraSetup::mPointListBodyLVS [mutable, protected]

Definition at line 147 of file OgreShadowCameraSetupFocused.h.

const Matrix4 Ogre::FocusedShadowCameraSetup::msLightSpaceToNormal [static, protected]

Definition at line 69 of file OgreShadowCameraSetupFocused.h.

const Matrix4 Ogre::FocusedShadowCameraSetup::msNormalToLightSpace [static, protected]

Transform to or from light space as defined by Wimmer et al.

Remarks:: Point and spot lights need to be converted to directional lights to enable a 1:1 light mapping. Otherwise a directional light may become a point light or a point sink (opposite of a light source) or point/spot lights may become directional lights or light sinks. The light direction is always -y.

Definition at line 68 of file OgreShadowCameraSetupFocused.h.

Frustum* Ogre::FocusedShadowCameraSetup::mTempFrustum [protected]

Temporary preallocated frustum to set up a projection matrix in calculateShadowMappingMatrix().

Definition at line 74 of file OgreShadowCameraSetupFocused.h.

bool Ogre::FocusedShadowCameraSetup::mUseAggressiveRegion [protected]

Use tighter focus region?

Definition at line 82 of file OgreShadowCameraSetupFocused.h.

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