Open Inventor Reference
SoRayPickAction Class Reference

Intersects objects with a ray cast into scene. More...

#include <Inventor/actions/SoRayPickAction.h>

Inheritance diagram for SoRayPickAction:
SoPickAction SoAction

Public Member Functions

 SoRayPickAction (const SbViewportRegion &viewportRegion)
 Constructor takes viewport region to use for picking. More...
 
virtual ~SoRayPickAction ()
 Destructor. More...
 
void setPoint (const SbVec2s &viewportPoint)
 Setting up the action before it is applied: More...
 
void setNormalizedPoint (const SbVec2f &normPoint)
 Sets the viewport point in normalized coordinates, which range from (0,0) at the lower left to (1,1) at the upper right. More...
 
void setRadius (float radiusInPixels)
 Set the radius (in pixels) around the point. More...
 
void setRay (const SbVec3f &start, const SbVec3f &direction, float nearDistance=-1.0, float farDistance=-1.0)
 Sets a world-space ray along which to pick. More...
 
void setPickAll (bool flag)
 Sets/returns whether the action will return all objects intersected or just the closest one. More...
 
bool isPickAll () const
 Sets/returns whether the action will return all objects intersected or just the closest one. More...
 
const SoPickedPointListgetPickedPointList () const
 Examining results after the action is applied: More...
 
SoPickedPointgetPickedPoint (int index=0) const
 Returns the indexed picked point from the list. More...
 
void computeWorldSpaceRay ()
 If a ray was not defined with setRay(), this causes the world space pick ray to be computed from the screen space point and radius, using the current view specification from the state. More...
 
bool hasWorldSpaceRay () const
 This returns TRUE if the action has had a world space ray set or computed. More...
 
void setObjectSpace ()
 This is called by shapes to set up object space picking. More...
 
void setObjectSpace (const SbMatrix &matrix)
 
bool intersect (const SbVec3f &v0, const SbVec3f &v1, const SbVec3f &v2, SbVec3f &intersection, SbVec3f &barycentric, bool &front) const
 These intersect the current object-space ray with a variety of primitives: triangle, line, point, bounding-box. More...
 
bool intersect (const SbVec3f &v0, const SbVec3f &v1, SbVec3f &intersection) const
 Line: More...
 
bool intersect (const SbVec3f &point) const
 Point: More...
 
bool intersect (const SbBox3f &box, bool useFullViewVolume=TRUE)
 Bounding box: just return whether the ray intersects it. More...
 
const SbViewVolumegetViewVolume () const
 Returns an SbViewVolume that represents the object-space ray to pick along. More...
 
const SbLinegetLine () const
 Returns SbLine that can be used for other intersection tests. More...
 
bool isBetweenPlanes (const SbVec3f &intersection) const
 Returns TRUE if the given object-space intersection point is between the near and far planes of the object-space view volume, as well as any clipping planes that have been defined. More...
 
SoPickedPointaddIntersection (const SbVec3f &objectSpacePoint)
 Adds an SoPickedPoint instance representing the given object space point to the current list and returns a pointer to it. More...
 
- Public Member Functions inherited from SoPickAction
void setViewportRegion (const SbViewportRegion &newRegion)
 Sets current viewport region to use for action. More...
 
const SbViewportRegiongetViewportRegion () const
 Returns current viewport region to use for action. More...
 
void enableCulling (bool flag)
 Setting this flag to FALSE disables any pick culling that might take place (as in SoSeparators). More...
 
bool isCullingEnabled () const
 
- Public Member Functions inherited from SoAction
virtual ~SoAction ()
 Destructor. More...
 
virtual SoType getTypeId () const =0
 Returns the type identifier for a specific instance. More...
 
bool isOfType (SoType type) const
 Returns TRUE if this instance is of the type specified in type or is derived from that type. More...
 
virtual void apply (SoNode *node)
 
virtual void apply (SoPath *path)
 
virtual void apply (const SoPathList &pathList, bool obeysRules=FALSE)
 Initiates an action on the graph defined either by a node, path, or list of paths. More...
 
virtual void invalidateState ()
 Invalidates the current traversal state in the action, forcing it to be recreated when the action is next applied. More...
 
AppliedCode getWhatAppliedTo () const
 Returns code indicating what action is being applied to. More...
 
SoNodegetNodeAppliedTo () const
 These returns a pointer to the node, path, or path list the action is being applied to. More...
 
SoPathgetPathAppliedTo () const
 
const SoPathListgetPathListAppliedTo () const
 A single path list may be split into several, one for each different head node. More...
 
const SoPathListgetOriginalPathListAppliedTo () const
 
bool isLastPathListAppliedTo () const
 
PathCode getPathCode (int &numIndices, const int *&indices)
 Returns path code based on where current node (the node at the end of the current path) lies with respect to the path(s) the action is being applied to. More...
 
void traverse (SoNode *node)
 Does traversal of a graph rooted by a node. More...
 
bool hasTerminated () const
 Returns TRUE if the traversal has reached a termination condition. More...
 
const SoPathgetCurPath ()
 Returns a pointer to the path accumulated during traversal, i.e., the chain of nodes from the root of the traversed graph to the current node being traversed. More...
 
SoStategetState () const
 Get the state from the action. More...
 
PathCode getCurPathCode () const
 These methods maintain the current path accumulated so far during traversal. More...
 
void pushCurPath (int childIndex)
 
void popCurPath (PathCode prevPathCode)
 
virtual SoNodegetCurPathTail ()
 This is virtual, so that SoCallbackAction can use current node. More...
 
void usePathCode (int &numIndices, const int *&indices)
 called by inline getPathCode: More...
 
void pushCurPath ()
 Optimized versions of push/pop when we know path codes won't change: More...
 
void popPushCurPath (int childIndex)
 
void popCurPath ()
 
const SoLightweightPathgetCurrentLightweightPath () const
 Returns the current "light" path. More...
 
void setCurrentLightweightPath (const SoLightweightPath &path)
 Sets the current "light" path. More...
 

Static Public Member Functions

static void initClass ()
 
- Static Public Member Functions inherited from SoPickAction
static void initClass ()
 
- Static Public Member Functions inherited from SoAction
static SoType getClassTypeId ()
 Returns the type identifier for this class. More...
 
static void nullAction (SoAction *, SoNode *)
 Null action method that can be stored in lookup table when desired. More...
 
static void initClass ()
 
static void initClasses ()
 Initialize ALL Inventor action classes. More...
 

Protected Member Functions

virtual void beginTraversal (SoNode *node)
 Initiates action on graph. More...
 
- Protected Member Functions inherited from SoPickAction
 SoPickAction (const SbViewportRegion &viewportRegion)
 Constructor takes viewport region. More...
 
virtual ~SoPickAction ()
 Destructor. More...
 
- Protected Member Functions inherited from SoAction
 SoAction ()
 Constructor. More...
 
virtual const SoEnabledElementsListgetEnabledElements () const
 Returns the list of enabled elements for a given action subclass. More...
 
void setTerminated (bool flag)
 Allows subclass instance to indicate that traversal has reached a termination condition. More...
 
virtual bool shouldCompactPathLists () const
 This method is used when applying an action to an SoPathList. More...
 

Additional Inherited Members

- Public Types inherited from SoAction
enum  AppliedCode { NODE , PATH , PATH_LIST }
 This enum is used to determine what the action is being applied to. More...
 
enum  PathCode { NO_PATH , IN_PATH , BELOW_PATH , OFF_PATH }
 This enum may be used during traversal of nodes to indicate where the node is with respect to the path being traversed. More...
 
- Protected Attributes inherited from SoPickAction
SbViewportRegion vpRegion
 Current viewport region. More...
 
- Protected Attributes inherited from SoAction
SoStatestate
 Traversal state. More...
 
SoActionMethodListtraversalMethods
 The list of what to do when. More...
 
- Static Protected Attributes inherited from SoAction
static SoEnabledElementsListenabledElements
 Holds list of enabled elements for the SoAction class. More...
 
static SoActionMethodListmethods
 ... and the methods More...
 

Detailed Description

This class performs picking by casting a ray into a scene and performing intersection tests with each object. The ray is extended to be a cone or cylinder, depending on the camera type, for intersection with points and lines. Each intersection is returned as an SoPickedPoint instance.

The picking ray can be specified as either a ray from the camera location through a particular viewport pixel, or as a world-space ray. In the former case, a valid camera must be encountered during traversal of the graph to determine the location of the ray in world space.

Callers can cause the action to compute all intersections along the ray (sorted closest to farthest) by setting the pickAll flag to TRUE. By default, the action computes only the closest intersection. In either case, the intersections are returned in an SoPickedPointList. Each intersection can be examined by accessing the appropriate SoPickedPoint in the list. The SoPickedPoint class provides methods to get the intersection point, normal, and other info.

See Also
SoPickedPoint, SoPickedPointList

Definition at line 97 of file SoRayPickAction.h.

Constructor & Destructor Documentation

◆ SoRayPickAction()

SoRayPickAction::SoRayPickAction ( const SbViewportRegion viewportRegion)

Even though the picking operation may not involve a window per se, some nodes need this information to determine their size and placement.

◆ ~SoRayPickAction()

virtual SoRayPickAction::~SoRayPickAction ( )
virtual

Member Function Documentation

◆ addIntersection()

SoPickedPoint* SoRayPickAction::addIntersection ( const SbVec3f objectSpacePoint)

If pickAll is TRUE, this inserts the instance in correct sorted order. If it is FALSE, it replaces the one instance in the list only if the new one is closer; if the new one is farther away, no instance is created and NULL is returned, meaning that no more work has to be done to set up the SoPickedPoint.

◆ beginTraversal()

virtual void SoRayPickAction::beginTraversal ( SoNode node)
protectedvirtual

Reimplemented from SoPickAction.

◆ computeWorldSpaceRay()

void SoRayPickAction::computeWorldSpaceRay ( )

This is typically done when a camera is encountered during traversal.

◆ getLine()

const SbLine& SoRayPickAction::getLine ( ) const
inline

The line's position is the starting point and the direction is the direction of the ray. Given an intersection with this ray, you can call isBetweenPlanes() to see if the intersection is between the near and far clipping planes.

Definition at line 232 of file SoRayPickAction.h.

◆ getPickedPoint()

SoPickedPoint* SoRayPickAction::getPickedPoint ( int  index = 0) const

◆ getPickedPointList()

const SoPickedPointList& SoRayPickAction::getPickedPointList ( ) const
inline

Returns list of picked points.

Definition at line 160 of file SoRayPickAction.h.

◆ getViewVolume()

const SbViewVolume& SoRayPickAction::getViewVolume ( ) const
inline

The projection point of the view volume is the starting point of the ray. The projection direction is the direction of the ray. The distance to the near plane is the same as the distance to the near plane for the ray. The distance to the far plane is the sum of the near distance and the depth of the view volume.

Definition at line 225 of file SoRayPickAction.h.

◆ hasWorldSpaceRay()

bool SoRayPickAction::hasWorldSpaceRay ( ) const

◆ initClass()

static void SoRayPickAction::initClass ( )
static

◆ intersect() [1/4]

bool SoRayPickAction::intersect ( const SbBox3f box,
bool  useFullViewVolume = TRUE 
)

If useFullViewVolume is TRUE, it intersects the picking view volume with the box. Otherwise, it uses just the picking ray, which is faster.

◆ intersect() [2/4]

bool SoRayPickAction::intersect ( const SbVec3f point) const

◆ intersect() [3/4]

bool SoRayPickAction::intersect ( const SbVec3f v0,
const SbVec3f v1,
const SbVec3f v2,
SbVec3f intersection,
SbVec3f barycentric,
bool &  front 
) const

Intersection with a triangle uses only the ray, while intersection with a line or point uses the cone or cylinder around the ray. The intersection with a bounding-box uses the cone/cylinder also, since the contents of the box may be lines or points. NOTE: you must call setObjectSpace() before calling any of these. Triangle: returns intersection point, barycentric coordinates, and whether the front side (defined by right-hand-rule) was hit.

◆ intersect() [4/4]

bool SoRayPickAction::intersect ( const SbVec3f v0,
const SbVec3f v1,
SbVec3f intersection 
) const

◆ isBetweenPlanes()

bool SoRayPickAction::isBetweenPlanes ( const SbVec3f intersection) const

This test can be used to determine whether the point of intersection of the ray with an object is valid with respect to the clipping planes.

◆ isPickAll()

bool SoRayPickAction::isPickAll ( ) const
inline

Definition at line 152 of file SoRayPickAction.h.

◆ setNormalizedPoint()

void SoRayPickAction::setNormalizedPoint ( const SbVec2f normPoint)

◆ setObjectSpace() [1/2]

void SoRayPickAction::setObjectSpace ( )

It uses the current state matrices to determine how to map between world and object spaces. It should be called before calling any of the intersection methods. The second form takes a matrix to concatenate with the current objToWorld matrix. It can be used, for example, if a shape has sizing or positioning info built into it.

◆ setObjectSpace() [2/2]

void SoRayPickAction::setObjectSpace ( const SbMatrix matrix)

◆ setPickAll()

void SoRayPickAction::setPickAll ( bool  flag)
inline

Definition at line 149 of file SoRayPickAction.h.

◆ setPoint()

void SoRayPickAction::setPoint ( const SbVec2s viewportPoint)

Sets the viewport-space point through which the ray passes, starting at the camera's viewpoint. Viewport coordinates range from (0,0) at the lower left to (width-1,height-1) at the upper right.

◆ setRadius()

void SoRayPickAction::setRadius ( float  radiusInPixels)

This is used when testing the ray against lines and points. By default, the radius is 5 pixels. For perspective cameras, the ray is extended to be a cone when testing against lines and points. For orthographic cameras, the ray is extended to be a cylinder. The radius has no effect for shapes of other types.

◆ setRay()

void SoRayPickAction::setRay ( const SbVec3f start,
const SbVec3f direction,
float  nearDistance = -1.0,
float  farDistance = -1.0 
)

The ray is defined as a world space starting point and direction vector. The direction vector will be normalized automatically. The last two arguments are the parametric distances between which intersections along the ray must occur. The distances are measured as if the direction vector is unit length; e.g., if nearDistance is 2.0, the intersection must occur past (start + 2*(length of the direction vector)) units along the ray. These distances can be used to achieve near and far plane clipping. A negative distance (such as the default values) means disable clipping to that plane.


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