Coin
4.0.3
Coin3D core library

The SbViewVolume class is a viewing volume in 3D space. More...
#include <Inventor/SbViewVolume.h>
Public Types  
enum  ProjectionType { ORTHOGRAPHIC = 0 , PERSPECTIVE = 1 } 
Public Attributes  
SbVec3f  llf 
SbVec3f  lrf 
float  nearDist 
float  nearToFar 
SbVec3f  projDir 
SbVec3f  projPoint 
ProjectionType  type 
SbVec3f  ulf 
The SbViewVolume class is a viewing volume in 3D space.
This class contains the necessary information for storing a view volume. It has methods for projection of primitives into the 3D volume from 2D points in the projection plane or vice versa, doing camera transforms, view volume transforms, etc.
An SbViewVolume instance can represent either an orthogonal projection volume or a perspective projection volume.
Enumerator  

ORTHOGRAPHIC  Orthographic projection. 
PERSPECTIVE  Perspective projection. 
SbViewVolume::SbViewVolume  (  void  ) 
Constructor. Note that the SbViewVolume instance will be uninitialized until you explicitly call ortho() or perspective().
SbViewVolume::~SbViewVolume  (  void  ) 
Destructor.
void SbViewVolume::frustum  (  float  left, 
float  right,  
float  bottom,  
float  top,  
float  nearval,  
float  farval ) 
Set up the frustum for perspective projection. This is an alternative to perspective() that lets you specify any kind of view volumes (e.g. off center volumes). It has the same arguments and functionality as the corresponding OpenGL glFrustum() function.
This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.
SbRotation SbViewVolume::getAlignRotation  (  SbBool  rightangleonly = FALSE  )  const 
Returns a rotation that aligns an object so that its positive xaxis is to the right and its positive yaxis is up in the view volume.
If rightangleonly is TRUE, it will create a rotation that aligns the x and yaxis with the closest orthogonal axes to right and up.
Returns a matrix which will translate the view volume camera back to origo, and rotate the camera so it'll point along the negative Zaxis.
Note that the matrix will not include the rotation necessary to make the camera up vector point along the positive Yaxis (i.e. camera roll is not accounted for).
float SbViewVolume::getDepth  (  void  )  const 
Returns depth of viewing frustum, i.e. the distance from the near clipping plane to the far clipping plane.
const SbDPViewVolume & SbViewVolume::getDPViewVolume  (  void  )  const 
Returns the double precision version of this view volume.
float SbViewVolume::getHeight  (  void  )  const 
Returns height of viewing frustum in the projection plane.
Returns the view volume's affine matrix and projection matrix.
Returns the combined affine and projection matrix.
float SbViewVolume::getNearDist  (  void  )  const 
Returns distance from projection plane to near clipping plane.
Returns an SbPlane instance which has a normal vector in the opposite direction of which the camera is pointing. This means the plane will be parallel to the near and far clipping planes.
Returns the direction of projection, i.e. the direction the camera is pointing.
Returns the projection point, i.e. the camera position.
SbViewVolume::ProjectionType SbViewVolume::getProjectionType  (  void  )  const 
Return current view volume projection type, which can be either ORTHOGRAPHIC or PERSPECTIVE.
Returns the point on the center lineofsight from the camera position with the given distance.
Returns the view up vector for this view volume. It's a vector which is perpendicular to the projection direction, and parallel and oriented in the same direction as the vector from the lower left corner to the upper left corner of the near plane.
Returns the six planes defining the view volume in the following order: left, bottom, right, top, near, far. Plane normals are directed into the view volume.
This method is an extension for Coin, and is not available in the original Open Inventor.
float SbViewVolume::getWidth  (  void  )  const 
Returns width of viewing frustum in the projection plane.
Given a sphere with center in worldCenter and an initial radius of 1.0, return the scale factor needed to make this sphere have a normRadius radius when projected onto the near clipping plane.
Returns TRUE if box may be inside the view volume.
Returns TRUE if p is inside the view volume.
SbBool SbViewVolume::intersect  (  const SbVec3f &  p0, 
const SbVec3f &  p1,  
SbVec3f &  closestpoint ) const 
Returns TRUE if the line segment p0, p1 may intersect volume. Be aware that it is not 100% certain that the line segment intersects the volume even if this function returns TRUE.
closestpoint is set to the closest point on the line to the center ray of the view volume.
Calculates the bbox of the intersection between bbox and the view volume.
SbViewVolume SbViewVolume::narrow  (  const SbBox3f &  box  )  const 
Returns a narrowed version of the view volume which is within the given [0, 1] normalized coordinates. The box x and y coordinates are taken to be corner points of a normalized "view window" on the near clipping plane. The box z coordinates are used to adjust the near and far clipping planes, and should be relative to the current clipping planes. A value of 1.0 is at the current near plane. A value of 0.0 is at the current far plane.
SbViewVolume SbViewVolume::narrow  (  float  left, 
float  bottom,  
float  right,  
float  top ) const 
Returns a narrowed version of the view volume which is within the given [0, 1] normalized coordinates. The coordinates are taken to be corner points of a normalized "view window" on the near clipping plane. I.e.:
..will give a view volume with corner points <25, 75> and <50, 100>.
void SbViewVolume::ortho  (  float  left, 
float  right,  
float  bottom,  
float  top,  
float  nearval,  
float  farval ) 
Set up the view volume as a rectangular box for orthographic parallel projections.
The line of sight will be along the negative Zaxis, through the center of the plane defined by the point
[(right+left)/2, (top+bottom)/2, 0]
SbBool SbViewVolume::outsideTest  (  const SbPlane &  p, 
const SbVec3f &  bmin,  
const SbVec3f &  bmax ) const 
Returns TRUE if all eight corner points in bmin, bmax is outside p.
void SbViewVolume::perspective  (  float  fovy, 
float  aspect,  
float  nearval,  
float  farval ) 
Set up the view volume for perspective projections. The line of sight will be through origo along the negative Zaxis.
Dump the state of this object to the fp file stream. Only works in debug version of library, method does nothing in an optimized build.
Projects the given box onto the projection plane and returns the normalized screen space it occupies.
Project the given 2D point from the projection plane into a 3D line.
pt coordinates should be normalized to be within [0, 1].
void SbViewVolume::projectPointToLine  (  const SbVec2f &  pt, 
SbVec3f &  line0,  
SbVec3f &  line1 ) const 
Project the given 2D point from the projection plane into two points defining a 3D line. The first point, line0, will be the corresponding point for the projection on the near plane, while line1 will be the line endpoint, lying in the far plane.
Project the src point to a normalized set of screen coordinates in the projection plane and place the result in dst.
It is safe to let src and dst be the same SbVec3f instance.
The zcoordinate of dst is monotonically increasing for points closer to the far plane. Note however that this is not a linear relationship, the dst zcoordinate is calculated as follows:
Orthogonal view: DSTz = (2 * SRCz  far  near) / (far  near), Perspective view: DSTz = (SRCz * (far  near)  2*far*near) / (far  near)
The returned coordinates (dst) are normalized to be in range [0, 1].
void SbViewVolume::rotateCamera  (  const SbRotation &  q  ) 
Rotate the direction which the camera is pointing in.
void SbViewVolume::scale  (  float  factor  ) 
Scale width and height of viewing frustum by the given ratio around the projection plane center axis.
void SbViewVolume::scaleHeight  (  float  ratio  ) 
Scale height of viewing frustum by the given ratio around the horizontal center axis in the projection plane.
void SbViewVolume::scaleWidth  (  float  ratio  ) 
Scale width of viewing frustum by the given ratio around the vertical center axis in the projection plane.
Translate the camera position of the view volume.
SbViewVolume SbViewVolume::zNarrow  (  float  nearval, 
float  farval ) const 
Return a copy SbViewVolume with narrowed depth by supplying parameters for new near and far clipping planes.
nearval and farval should be relative to the current clipping planes. A value of 1.0 is at the current near plane. A value of 0.0 is at the current far plane.
Return the vector pointing from the center of the view volume towards the camera. This is just the vector pointing in the opposite direction of getProjectionDirection().
SbVec3f SbViewVolume::llf 
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
SbVec3f SbViewVolume::lrf 
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
float SbViewVolume::nearDist 
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
float SbViewVolume::nearToFar 
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
SbVec3f SbViewVolume::projDir 
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
SbVec3f SbViewVolume::projPoint 
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
SbViewVolume::ProjectionType SbViewVolume::type 
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.
SbVec3f SbViewVolume::ulf 
This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.