SoDragger.h

/*=======================================================================
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/*=======================================================================
** Author      : Paul Isaacs (MMM yyyy)
** Modified by : David Mott (MMM yyyy)
** Modified by : Howard Look (MMM yyyy)
**=======================================================================*/
/*=======================================================================
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**=======================================================================*/
/*=======================================================================
** Modified by : VSG (MMM YYYY)
**=======================================================================*/
 
 
#ifndef  _SO_DRAGGER_
#define  _SO_DRAGGER_
 
#include <Inventor/SbBox.h>
#include <Inventor/SbViewportRegion.h>
#include <Inventor/SbLinear.h>
#include <Inventor/nodekits/SoInteractionKit.h>
#include <Inventor/misc/SoCallbackList.h>
#include <Inventor/fields/SoSFBool.h>
#include <Inventor/nodes/SoMatrixTransform.h>
#include <Inventor/nodes/SoScale.h>
 
 
class SoPickedPoint;
class SoAction;
class SoHandleEventAction;
class SoGetBoundingBoxAction;
class SoGetMatrixAction;
class SoSearchAction;
class SoEvent;
class SoPath;
class SoTempPath;
class SbPList;
 
class SoDragger;  // forward reference

typedef void SoDraggerCB(void *userData, SoDragger *dragger );

//
//  Class: SoDragger
//
//  Base class for draggers which are operated by a start (mouse down)
//  followed by dragging, followed by end (mouse up).
//

class  SoDragger : public SoInteractionKit {
 
  SO_KIT_HEADER(SoDragger);
 
  SO_KIT_CATALOG_ENTRY_HEADER(motionMatrix);
 
 public:

  SoSFBool  isActive;

  SoSFBool  enableCallbacks;
 
  // Dragger Callbacks
  // In all cases, the callback data will be a pointer to the dragger
  // that caused the callback. Each type of callback maintains a list of
  // callbacks, so many callback functions may be registered, if desired.

  void    addStartCallback(SoDraggerCB *f, void *userData = NULL);

  void removeStartCallback(SoDraggerCB *f, void *userData = NULL);

  void    addMotionCallback(SoDraggerCB *f, void *userData = NULL);

  void removeMotionCallback(SoDraggerCB *f, void *userData = NULL);

  void    addFinishCallback(SoDraggerCB *f, void *userData = NULL);

  void removeFinishCallback(SoDraggerCB *f, void *userData = NULL);

  void    addValueChangedCallback(SoDraggerCB *f, void *userData = NULL);

  void removeValueChangedCallback(SoDraggerCB *f, void *userData = NULL);

  void    setMinGesture(int pixels)       { minGesture = (float)pixels; }

  void    setMinGesture(float pixels)       { minGesture = pixels; }

  int     getMinGesture() const           { return (int)minGesture; }

  float   getMinGestureFloat() const           { return minGesture; }

  static void  setMinScale(float newMinScale);

  static float getMinScale();

  SbBool enableValueChangedCallbacks( SbBool newVal );

  enum TrackerDirectMode {
    NONE,
    MOVE,
    ROTATE,
    FREE,
    DEFAULT
  };

  void setTrackerDirectMode( TrackerDirectMode mode = DEFAULT );

  TrackerDirectMode getTrackerDirectMode() const;

  static void setInitialTrackerDirectMode( TrackerDirectMode mode = DEFAULT );

  static TrackerDirectMode getInitialTrackerDirectMode();

  void            setMotionMatrix( const SbMatrix &newMatrix );

  const SbMatrix &getMotionMatrix();
 
 private:
 
  // In addition to the public callback functions, these callback
  // functions can also be used by subclasses to find out when things
  // have happened.
 
  // otherEvent callbacks are called in response to events other than
  // the button1 Press/Release and location/tracker.
  void addOtherEventCallback(SoDraggerCB *f, void *userData = NULL);
  void removeOtherEventCallback(SoDraggerCB *f, void *userData = NULL);
  void clearOtherEventCallbacks();
 
  // Compound draggers should call this for each child dragger
  // so that user callbacks (valueChanged, start, motion, finish, other event)
  // registered with the parent dragger will be invoked based on the child
  // dragger.  Also, this will add the 'transferMotion' callback as a
  // valueChanged callback on the child. Child dragger enableCallbacks field
  // will be automatically connected from parent dragger enableCallbacks field, 
  // so that when parent dragger enableCallbacks field is set, value is the same 
  // for child draggers
  void registerChildDragger(SoDragger *child);
  void unregisterChildDragger(SoDragger *child);
 
  // These two routines tie the child to the parent, but WITHOUT the
  // transferMotion callback. It is good
  // for child draggers that need to move independently of their parents,
  // but which should still call the parents (valueChanged, start, motion,
  // end, and otherEvent) callbacks when they are dragged.
  void registerChildDraggerMovingIndependently(SoDragger *child);
  void unregisterChildDraggerMovingIndependently(SoDragger *child);
 
  // Get the matrix which converts from one dragger space to another.
  SbMatrix getLocalToWorldMatrix( SoAction* action = NULL );
  SbMatrix getWorldToLocalMatrix( SoAction* action = NULL );
 
  // Returns the starting point in local coordinates.
  SbVec3f     getLocalStartingPoint();
  // Returns the starting point in world coordinates.
  SbVec3f     getWorldStartingPoint();
 
  // Get the matrix which converts from the space of one part into
  // local space. Good to use if transforms occur between 'motionMatrix'
  // and the space you want to work in.
  // Note: This routine will try not to create parts that don't exist.
  //       Instead it finds the existing part that precedes it in traversal.
  //       But this only works if the partName is in this nodekit's catalog.
  //       If the part is nested within another kit below this one or
  //       sitting inside a list part, the part will be created when it
  //       doesn't exist.
  void getPartToLocalMatrix( const SbName &partName,
                             SbMatrix &partToLocalMatrix,
                             SbMatrix &localToPartMatrix);
 
  // Transforms a given matrix from one space into another space
  void  transformMatrixLocalToWorld( const SbMatrix &fromMatrix,
                                     SbMatrix &toMatrix);
  void  transformMatrixWorldToLocal( const SbMatrix &fromMatrix,
                                     SbMatrix &toMatrix);
  void  transformMatrixToLocalSpace( const SbMatrix &fromMatrix,
                                     SbMatrix &toMatrix, const SbName &fromSpacePartName);
 
  // Invokes the valueChangedCallbacks.
  // These are invoked whenever setMotionMatrix() changes the motion matrix.
  // If a subclass wishes to invoke the valueChanged callbacks for some
  // other reason, they may call valueChanged(). Example: SoSpotLightDragger
  // changes its angle field without altering the motionMatrix. So it
  // calls valueChanged() to invoke callbacks.
 
  void valueChanged();
 
  // Used to calculate motion relative to the dragger's position at the
  // beginning of the dragging.
  const SbMatrix &getStartMotionMatrix() { return startMotionMatrix; }
 
  // By default, saves the motionMatrix as the startMotionMatrix.
  // Subclasses may want to save additional info. For example, the
  // centerballDragger also saves the matrix that moves the center relative
  // to the motionMatrix.
  virtual void saveStartParameters();
 
  // Information that's good to have during a valueChanged callback
  const SoPath              *getPickPath()       const;
  const SoEvent             *getEvent() const;
 
  // Creates a new path leading to this dragger, if the last path given by
  // setTempPathToThis()  is still valid.  Will return NULL if not possible.
  // You must ref() and unref() this new path if you
  // don't want it (and all the nodes along it) to stay around forever.
  SoPath                    *createPathToThis();
 
  // Surrogate Pick Information. This is relevant if the we are dragging
  // based on the pick of a surrogate part. This happens when you call
  // SoInteractionKit::setPartAsPath() and thus specify a 'stand-in' path
  // to pick when initiating a drag.
  // Owner:
  //       Path to the InteractionKit that owns the surrogate part.
  const SoPath *getSurrogatePartPickedOwner() const
    { return pathToSurrogatePickOwner;}
  // Name:
  //       Name of the surrogate part within the owners list.
  const SbName &getSurrogatePartPickedName() const
    { return surrogateNameInPickOwner; }
  // SurrogatePath:
  //        The owner's surrogate path for this name. This path may
  //        differ from the actual pickPath, but it is guaranteed to
  //        be contained within the pickPath.
  const SoPath *getSurrogatePartPickedPath() const
    { return surrogatePathInPickOwner;}
 
  // Set the point where the drag begins.
  // The pickedPoint version would usually be the result of a pick.
  void setStartingPoint( const SoPickedPoint *newPoint );
  // The SbVec3f version would usually be a point saved from the end of
  // another gesture. For example, when a modifier key goes down, we might
  // save the current position and use it to begin another connected gesture.
  void setStartingPoint( const SbVec3f &newPoint );
 
  // Information about the window an event occurred in.
  // Upon construction, the values are defaults.
  // When drag begins, new values are taken from the handleEventAction
  // and used for the duration of the drag.
  // When drag ends, new values are taken from the final handleEventAction.
  //
  // DEPRECATED SINCE OIV 9.3
  // Dragger must not store information related to viewer settings.
  // In a multi-viewers configuration, draggers internal computation can be
  // corrupted by using one of these values set from another viewer
  // This has been solved by directly getting viewvolume and viewport from
  // the state, or from the current action.
 
#if 1             
SoDEPRECATED
  const SbViewVolume      &getViewVolume() { return viewVolume; }
SoDEPRECATED
  void  setViewVolume(const SbViewVolume &vol) { viewVolume = vol; }
SoDEPRECATED
  const SbViewportRegion  &getViewportRegion() { return vpRegion; }
SoDEPRECATED
  void  setViewportRegion(const  SbViewportRegion &reg) { vpRegion = reg; }
 
#endif 
 
  // Get the most recent handleEventAction.
  SoHandleEventAction *getHandleEventAction() const { return handleEventAction; }
  void setHandleEventAction( SoHandleEventAction *newAction );
 
  // A path leading to 'this.' It is used to calculate the
  // motionMatrix. It is set when a dragger first grabs event, through the
  // handleEvent action, or by setCameraInfo() if NULL at the time.
  void                setTempPathToThis(const SoPath *somethingClose);
 
  // Called when the dragger gains or loses status as "grabber" of events.
  virtual void grabEventsSetup();
  virtual void grabEventsCleanup();
 
  // Changes only that part of the matrix for which this dragger has fields.
  // For instance, when called by an SoTranslate1Dragger, any rotations and
  // scales in the matrix will remain unchanged. But the translation will
  // be replaced with value in the 'translation' field.
  //   First, factor mtx to get values for the following:
  //      trans, rot, scale, scaleOrient.
  //      If there's a center field, send it to the factor method.
  //   Replace any of these four values if fields are found named
  //     'translation' 'scaleFactor' 'rotation' and/or 'scaleOrientation'
  //     Note that this could be all or none of the 4 listed.
  //     Values for which no fields are found remain unchanged.
  //   Build a new matrix using the new values. Some may be the originals
  //     and some may have been replaced.
  void workFieldsIntoTransform( SbMatrix &mtx );
 
  // Same as above, but values are given explicitly as pointers.
  // If the pointers are NULL, the values in the matrix are not changed.
  static void workValuesIntoTransform( SbMatrix &mtx,
                                       const SbVec3f *translationPtr,
                                       const SbRotation *rotationPtr,
                                       const SbVec3f *scaleFactorPtr,
                                       const SbRotation *scaleOrientationPtr,
                                       const SbVec3f *centerPtr);
 
  // Faster versions of getTransform() and factor() that take advantage of
  // the case where there is no scaleOrientation. Reverts to slow method
  // if it needs to.
  // This method will not work if the matrix given contains any scales
  // less than zero, and it does not check for that case.
  static void getTransformFast( SbMatrix &mtx, SbVec3f &translation,
                                SbRotation &rotation, SbVec3f &scaleFactor,
                                SbRotation &scaleOrientation,
                                const SbVec3f &center);
  static void getTransformFast( SbMatrix &mtx, SbVec3f &translation,
                                SbRotation &rotation, SbVec3f &scaleFactor,
                                SbRotation &scaleOrientation);
 
  // Appends the given motion to the end of 'mtx'.
  // 'conversion' transforms from the space the motion is defined in
  // to the space 'mtx'.
  static SbMatrix appendTranslation( const SbMatrix &mtx,
                                     const SbVec3f &translation,
                                     const SbMatrix *conversion = NULL );
  static SbMatrix appendScale( const SbMatrix &mtx,
                               const SbVec3f &scale, const SbVec3f &scaleCenter,
                               const SbMatrix *conversion = NULL );
  static SbMatrix appendRotation( const SbMatrix &mtx,
                                  const SbRotation &rot, const SbVec3f &rotCenter,
                                  const SbMatrix *conversion = NULL );
 
  // Is the current tracker direct mode MOVE, ROTATE or FREE ?
  SbBool isTrackerDirectMode() const;
 
 private:
  void GLRender(SoGLRenderAction *action);
 
  static void initClass();
  static void exitClass();
  SB_THREAD_TLS_HEADER();
 
  // Initialize ALL Inventor dragger classes
  static void initClasses();
  static void exitClasses();
 
  // These control behavior of the rotational parts. If FRONT, no matter
  // where you hit the dragger relative to its center, it will behave as if
  // you are dragging from the front. If BACK, the rear. If USE_PICK,
  // then it depends on the relationship between the picked point and the
  // center of the dragger.
  enum ProjectorFrontSetting {
    FRONT, BACK, USE_PICK
  };
  void setFrontOnProjector( ProjectorFrontSetting newVal )
    { projectorFrontSetting = newVal; }
  ProjectorFrontSetting getFrontOnProjector() const
    { return projectorFrontSetting;}
 
  inline void setInteracting(bool flag) { m_draggerInteracting = flag; }
 
 private:
 
  // Constructor
  SoDragger();
 
  // Sensor attached to enableCallbacks field
  SoFieldSensor* m_enableSensor;
 
  //Field sensor callback
  static void enableCB( void *, SoSensor * );
 
  // Get the last known position of the locator (mouse).
  // 2D locater positions have (0,0) at lower-left, and are
  // relative to the viewport.
  // Normalized positions go from 0.0 to 1.0.
  // Regular positions go from 0 to (vpSize - 1)
  SbVec2f     getNormalizedLocaterPosition();
  const SbVec2f&     getLocaterPosition();
 
  // Get the 3D tracker device's ray in world coords (new in v3.0)
  SbLine  getTrackerRay();
 
  // Get the position of the locater when dragging started.
  const SbVec2f&     getStartLocaterPosition() const     { return startLocater; }
 
  // The start locater position is automatically set when button 1
  // goes down over the dragger. Subclasses may wish to reset it, such
  // as when a constraint key goes down during dragging.
  void        setStartLocaterPosition(const SbVec2f& p)   { startLocater = p; }
 
  // Has the locater moved far enough from where it started to
  // choose a constraint gesture.
  SbBool      isAdequateConstraintMotion();
 
  // Given a pickPath and a surrogatePath, decides whether it should
  // grab based on the surrogate. First, the pickPath must
  // contain the surrogatePath, indicating that the surrogate was picked.
  // Second, we consider the part of the pickPath below the point where
  // the surrogatePath ends.
  // If this bottom section contains other draggers, then we will pass it up.
  // This is because the other draggers will want to grab when they find out
  // they've been picked.
  virtual SbBool shouldGrabBasedOnSurrogate( const SoPath *pickPath,
                                             const SoPath *surrogatePath );
 
  //
  // The dragger looks in this action to get information about the camera
  // and the viewport.  Usually the action used is just the handleEventAction.
  void setCameraInfo( SoAction *action );
 
  // This is called during traversal by a HandleEventAction. It
  // calls ha->setHandled() if the event is handled.
  virtual void               handleEvent(SoHandleEventAction *ha);
 
  // This should be called by every child dragger of a compound dragger
  // as a result of compoundDragger->registerChildDragger( childDragger );
  // Called on the compoundDragger when childDragger's value changes.
  // Gets the motionMatrix from a the child dragger. Appends that change
  // to the parent dragger's savedStartMatrix, and sets the result as the
  // parent's motionMatrix.
  // Then, it zeros out the motionMatrix of the child dragger.
  void transferMotion(SoDragger *child);
 
  // Set/get whether the dragger should be ignored during bounding
  // box calculations.
  void    setIgnoreInBbox( SbBool newVal ) { ignoreInBbox = newVal; }
  SbBool  isIgnoreInBbox() { return ignoreInBbox; }
 
  // Implements getBoundingBox action. Differs from separator as follows:
  // If the 'ignoreInBbox' flag is set to TRUE, then it will return without
  // traversing children.
  virtual void        getBoundingBox(SoGetBoundingBoxAction *action);
 
  // Stubs used by compound draggers to get user callbacks from
  // the child dragger
  static void childTransferMotionAndValueChangedCB(void *, SoDragger *);
  static void childValueChangedCB(void *, SoDragger *);
  static void childStartCB(void *, SoDragger *);
  static void childMotionCB(void *, SoDragger *);
  static void childFinishCB(void *, SoDragger *);
  static void childOtherEventCB(void *, SoDragger *);
 
  // Called by the above child callbacks. Establishes which child dragger
  // is currently active. Set at beginning of child callback, returned to
  // original value at end. Returns current value at time method is called.
  void       setActiveChildDragger( SoDragger *newChildDragger );
  SoDragger *getActiveChildDragger() const { return activeChildDragger; }
 
  // Called by the SoBaseKit::write() method.
  //
  // Draggers don't want to write out fields if they have default vals.
  //
  // sets isActive to default if default and not connected.
  //
  // Looks for fields named:
  //    'rotation'    with value SbRotation::identity()
  //    'translation' with value (0,0,0)
  //    'center'      with value (0,0,0)
  //    'scaleFactor' with value (1,1,1)
  // and sets them to default if they are not connected from a field.
  // (most draggers are missing at least some of these, but thats okay)
  //
  // Then calls the method for SoInteractionKit.
  //
  // NOTE: Parts which are set to default may still wind up writing to file
  //       if, for example, they lie on a path.
  virtual void setDefaultOnNonWritingFields();
 
  // In tracker direct mode, apply motion of tracked input device
  // directly to dragger's motion matrix.  (new for v5.0)
  virtual SbBool applyTrackerMotion();
 
  virtual ~SoDragger();
 
  // Class static thread local storage
  struct MTstruct {
    SoGetMatrixAction *m_matrixAction;
    SoSearchAction    *m_searchAction;
  };
 
  // Support for tracker direct mode (for immersive environments)
  //
  // Allows direct mode to be set for all draggers
  static TrackerDirectMode m_initialDirectMode;
  // Current direct mode for this dragger instance
  TrackerDirectMode        m_directMode;
  // Default direct mode for this class of dragger
  TrackerDirectMode        m_defaultDirectMode;
  // Saved start position of tracked input device
  SbVec3f                  m_trackerStartPos;
  // Saved start orientation of tracked input device
  SbRotation               m_trackerStartRot;
 
  SbViewVolume        viewVolume;         // view volume for xsection tests
  SbViewportRegion    vpRegion;           // view volume for xsection tests
 
 private:
 
  // lists of callback functions
  SoCallbackList      *startCallbacks;
  SoCallbackList      *motionCallbacks;
  SoCallbackList      *finishCallbacks;
  SoCallbackList      *valueChangedCallbacks;
 
  SoCallbackList      *otherEventCallbacks;
 
  SbBool    valueChangedCallbacksEnabled;
  SoDragger *activeChildDragger;
 
  SoHandleEventAction *handleEventAction; // current event action
 
  // A record of the world space point which initiated the dragging.
  // This might be set from a pickedPoint of a handleEventAction,
  // or explicitly from a given point when a meta-key callback
  // changes gestures mid-stream and wants to select its own transitional
  // starting point.
  SbVec3f             startingWorldPoint;
 
  // Used by parent draggers to save initial matrix when motion begins.
  SbMatrix startMotionMatrix;
 
  // Where the locater was when dragging was initiated
  SbVec2f     startLocater;
 
 
  // sets pick path and tempPathToThis
  void                setPickPath(SoPath *newPickPath);
  SoPath              *pickPath;          // pick path to the dragger
 
  // sets surrogate part picks.
  void setNoPickedSurrogate();
  void setPickedSurrogate( SoPath *pathToOwner, SbName &nameUsedByOwner,
                           SoPath *pathUsedByOwner );
 
  SbName surrogateNameInPickOwner;
  SoPath *pathToSurrogatePickOwner;
  SoPath *surrogatePathInPickOwner;
 
  // A tempPath leading to 'this.' It is used to calculate the
  // motionMatrix. It is set when a dragger first grabs event, through the
  // handleEvent action, or by setCameraInfo() if NULL at the time.
  // A tempPath does not increase any ref counts, so keeping this path
  // will not prevent this node from being deleted. However, we must be
  // very careful before using it, since some nodes my get deleted out from
  // under us. The variable tempPathNumKidsHack helps us fix up paths
  // that have changed since the path was set.
  SoTempPath          *tempPathToThis;
  SbPList             *tempPathNumKidsHack;
  // Determines if this path can actually be used. Since a temp path
  // does not ref the nodes, some nodes my get deleted out from
  // under us. This routine makes sure that everythings all right.
  SbBool              isTempPathToThisOk();
  // Creates a temp path copy of the full path.
  SoTempPath      *createTempPathFromFullPath( const SoFullPath *fp ) const;
 
  // Minimum number of pixels to move before choosing a constraint
  // based on the gesture.
  float         minGesture;
 
  // The smallest scale that any dragger will write. If the user attempts
  // to go below this amount, the dragger will set it to this minimum.
  // Default is .0001
  static float       minScale;
 
  // We keep these matrices and their inverses around
  // to use when converting between spaces. The four
  // pairs are cached; the pair becomes invalud when its
  // valid flag is set to FALSE.
 
  // Called to make sure these matrixes are up to date.
  void validateMatrices( SoAction* );
 
  // These matrices are ones that are commonly queried by
  // subclasses. So, we cache them.
  // Two things determine the localToWorld matrix. The pathToThis and
  // the motionMatrix. If either value is invalid, we need to recalculate.
  // But depending on which one it is, we either need to run a matrix
  // action on the pick path or just on the motionMatrix.
  SbBool   cachedPathToThisValid;
  SbBool   cachedMotionMatrixValid;
  SbMatrix cachedMotionMatrix;
  // PostMotion is the matrix space just AFTER the motion matrix.
  SbMatrix postMotionToWorldMatrix;
  SbMatrix worldToPostMotionMatrix;
  // PreMotion is the matrix space just BEFORE the motion matrix.
  SbMatrix preMotionToWorldMatrix;
  SbMatrix worldToPreMotionMatrix;
 
  // Used so that draggers don't try to include themselves
  // as part of their own sizing boxes. By default this is FALSE.
  SbBool ignoreInBbox;
 
  // True if we are interacting in order to update the SoInteractionElement
  bool m_draggerInteracting;
 
  ProjectorFrontSetting projectorFrontSetting;
};
 
#endif /* _SO_DRAGGER_ */