OpenGl_BVHTreeSelector Class Reference

BVHTreeSelector class provides a possibility to store parameters of view volume, such as its vertices and equations, and contains methods detecting if given AABB overlaps view volume. More...

#include <OpenGl_BVHTreeSelector.hxx>

Public Member Functions
	OpenGl_BVHTreeSelector ()
	Creates an empty selector object with parallel projection type by default. More...
void	SetViewVolume (const Handle< Graphic3d_Camera > &theCamera)
	Retrieves view volume's planes equations and its vertices from projection and modelview matrices. More...
Standard_Boolean	Intersect (const OpenGl_Vec4 &theMinPt, const OpenGl_Vec4 &theMaxPt) const
	Detects if AABB overlaps view volume using separating axis theorem (SAT). More...
void	CacheClipPtsProjections ()
	Caches view volume's vertices projections along its normals and AABBs dimensions. Must be called at the beginning of each BVH tree traverse loop. More...
const Standard_Size	ProjectionState ()
	Returnes the state of projection matrix previously saved in selector. More...
Standard_Size &	ChangeProjectionState ()
	Returnes the link for changing the state of projection matrix. More...
const Standard_Size	ModelViewState ()
	Returnes the state of model view matrix previously saved in selector. More...
Standard_Size &	ChangeModelViewState ()
	Returnes the link for changing the state of model view matrix. More...

Protected Types
enum	{   Plane_Top, Plane_Bottom, Plane_Left, Plane_Right,   Plane_Near, Plane_Far, PlanesNB }
	Enumerates planes of view volume. More...
enum	{   ClipVert_LeftTopNear, ClipVert_LeftBottomNear, ClipVert_RightTopNear, ClipVert_RightBottomNear,   ClipVert_LeftTopFar, ClipVert_LeftBottomFar, ClipVert_RightTopFar, ClipVert_RightBottomFar,   ClipVerticesNB }
	Enumerates vertices of view volume. More...

Protected Member Functions
Standard_ShortReal	SignedPlanePointDistance (const OpenGl_Vec4 &theNormal, const OpenGl_Vec4 &thePnt)
	Calculates signed distance from plane to point. More...

Protected Attributes
OpenGl_Vec4	myClipPlanes [PlanesNB]
	Plane equations. More...
OpenGl_Vec4	myClipVerts [ClipVerticesNB]
	Vertices. More...
Standard_ShortReal	myMaxClipProjectionPts [PlanesNB]
	Max view volume's vertices projections onto its normals. More...
Standard_ShortReal	myMinClipProjectionPts [PlanesNB]
	Min view volume's vertices projections onto its normals. More...
Standard_ShortReal	myMaxOrthoProjectionPts [3]
	Max view volume's vertices projections onto normalized dimensions of AABB. More...
Standard_ShortReal	myMinOrthoProjectionPts [3]
	Min view volume's vertices projections onto normalized dimensions of AABB. More...
Standard_Boolean	myIsProjectionParallel
Standard_Size	myProjectionState
Standard_Size	myModelViewState
	Caches the state of projection matrix to prevent unnecessary updates. More...

Detailed Description

BVHTreeSelector class provides a possibility to store parameters of view volume, such as its vertices and equations, and contains methods detecting if given AABB overlaps view volume.

Member Enumeration Documentation

anonymous enum

protected

Enumerates planes of view volume.

Enumerator
Plane_Top
Plane_Bottom
Plane_Left
Plane_Right
Plane_Near
Plane_Far
PlanesNB

anonymous enum

protected

Enumerates vertices of view volume.

Enumerator
ClipVert_LeftTopNear
ClipVert_LeftBottomNear
ClipVert_RightTopNear
ClipVert_RightBottomNear
ClipVert_LeftTopFar
ClipVert_LeftBottomFar
ClipVert_RightTopFar
ClipVert_RightBottomFar
ClipVerticesNB

Constructor & Destructor Documentation

OpenGl_BVHTreeSelector::OpenGl_BVHTreeSelector

(

)

Creates an empty selector object with parallel projection type by default.

Member Function Documentation

void OpenGl_BVHTreeSelector::CacheClipPtsProjections

(

)

Caches view volume's vertices projections along its normals and AABBs dimensions. Must be called at the beginning of each BVH tree traverse loop.

Standard_Size& OpenGl_BVHTreeSelector::ChangeModelViewState ( )

inline

Returnes the link for changing the state of model view matrix.

Standard_Size& OpenGl_BVHTreeSelector::ChangeProjectionState ( )

inline

Returnes the link for changing the state of projection matrix.

Standard_Boolean OpenGl_BVHTreeSelector::Intersect	(	const OpenGl_Vec4 &	theMinPt,
		const OpenGl_Vec4 &	theMaxPt
	)		const

Detects if AABB overlaps view volume using separating axis theorem (SAT).

Parameters

theMinPt	[in] maximum point of AABB.
theMaxPt	[in] minimum point of AABB.

Returns

Standard_True, if AABB is in viewing area, Standard_False otherwise.

const Standard_Size OpenGl_BVHTreeSelector::ModelViewState ( )

inline

Returnes the state of model view matrix previously saved in selector.

const Standard_Size OpenGl_BVHTreeSelector::ProjectionState ( )

inline

Returnes the state of projection matrix previously saved in selector.

void OpenGl_BVHTreeSelector::SetViewVolume

(

const Handle< Graphic3d_Camera > &

theCamera

)

Retrieves view volume's planes equations and its vertices from projection and modelview matrices.

Standard_ShortReal OpenGl_BVHTreeSelector::SignedPlanePointDistance ( const OpenGl_Vec4 &  theNormal, const OpenGl_Vec4 &  thePnt  )

protected

Calculates signed distance from plane to point.

Parameters

theNormal	[in] the plane's normal.
thePnt	[in]

Field Documentation

OpenGl_Vec4 OpenGl_BVHTreeSelector::myClipPlanes[PlanesNB]

protected

Plane equations.

OpenGl_Vec4 OpenGl_BVHTreeSelector::myClipVerts[ClipVerticesNB]

protected

Vertices.

Standard_Boolean OpenGl_BVHTreeSelector::myIsProjectionParallel

protected

Standard_ShortReal OpenGl_BVHTreeSelector::myMaxClipProjectionPts[PlanesNB]

protected

Max view volume's vertices projections onto its normals.

Standard_ShortReal OpenGl_BVHTreeSelector::myMaxOrthoProjectionPts[3]

protected

Max view volume's vertices projections onto normalized dimensions of AABB.

Standard_ShortReal OpenGl_BVHTreeSelector::myMinClipProjectionPts[PlanesNB]

protected

Min view volume's vertices projections onto its normals.

Standard_ShortReal OpenGl_BVHTreeSelector::myMinOrthoProjectionPts[3]

protected

Min view volume's vertices projections onto normalized dimensions of AABB.

Standard_Size OpenGl_BVHTreeSelector::myModelViewState

protected

Caches the state of projection matrix to prevent unnecessary updates.

Standard_Size OpenGl_BVHTreeSelector::myProjectionState

protected

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

• OpenGl_BVHTreeSelector.hxx