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NAME

       SoState -

       The SoState class manages the Coin scenegraph traversal state data.

       The SoState class is used by actions derived from the SoAction class.
       It manages the scenegraph state as stacks of elements (ie instances of
       classes derived from SoElement).

SYNOPSIS

       #include <Inventor/misc/SoState.h>

   Public Member Functions
       SoState (SoAction *action, const SoTypeList &enabledelements)
       ~SoState (void)
       SoAction * getAction (void) const
       SoElement * getElement (const int stackindex)
       const SoElement * getConstElement (const int stackindex) const
       void push (void)
       void pop (void)
       void print (FILE *const file=stdout) const
       SbBool isElementEnabled (const int stackindex) const
       int getDepth (void) const
       void setCacheOpen (const SbBool flag)
       SbBool isCacheOpen (void) const
       SoElement * getElementNoPush (const int stackindex) const

Detailed Description

       The SoState class manages the Coin scenegraph traversal state data.

       The SoState class is used by actions derived from the SoAction class.
       It manages the scenegraph state as stacks of elements (ie instances of
       classes derived from SoElement).

       For more information on the inner workings of traversal states in Coin,
       we recommend the book «The Inventor Toolmaker» (ISBN 0-201-62493-1),
       also available at SGI’s online library. Search for ’Toolmaker’.

Constructor & Destructor Documentation

   SoState::SoState (SoAction * theAction, const SoTypeList & enabledelements)
       The constructor. The theAction argument is the action object the state
       is part of, and the enabledElements argument is an SoTypeList of the
       elements that are enabled for this action.
       The constructor pushes a default element onto the indexes of all the
       enabled element stacks. SoElement::push() is not called on the initial
       elements in the SoState stacks, but SoElement::init() is.

   SoState::~SoState (void) The destructor.
       Note that when destruction happens, lagging events caused by lazy
       evaluation won’t be performed.

Member Function Documentation

   SoAction * SoState::getAction (void) const This method returns the pointer
       to the action instance given to the constructor.
   SoElement * SoState::getElement (const int stackindex) This method returns
       a modifyable instance of the element on the top of the stack with the
       given stackindex. Because of lazy programming, this function may need
       to do some work, so SoState::getConstElement() should be used instead
       whenever possible.
   const SoElement * SoState::getConstElement (const int stackIndex) const
       [inline] This method returns a pointer to the top element of the given
       element stack. The element is read-only and must not be changed under
       any circumstances or strange side-effect will occur.
       Note that this function will assert if the element with the given stack
       identity value is not presently on the state stack. To check whether or
       not an element is present in the stack, use
       SoState::isElementEnabled().

   void SoState::push (void) This method pushes the state one level down. This
       saves the state so it can be changed and later restored to this state
       by calling SoState::pop().
       The push and pop mechanism is performed lazily for efficiency reasons
       (avoids a lot of memory allocation and copying). Only when a state
       element is actually going to be changed, that element will be pushed
       for real.

   void SoState::pop (void) This method pops the state to restore it to a
       previous state. Pops are performed eagerly but the code is very tight
       so there is no reason to worry about efficiency.
   void SoState::print (FILE *const  file = stdout) const This method is just
       for debugging purposes.
   SbBool SoState::isElementEnabled (const int stackindex) const [inline] This
       method returns TRUE if the element with the given element stack index
       is enabled, and FALSE otherwise.
   int SoState::getDepth (void) const This method returns the current depth of
       the state stack.
       The depth is ’virtual’, not necessarily physical.

   void SoState::setCacheOpen (const SbBool open) Controls whether a cache is
       open.
   SbBool SoState::isCacheOpen (void) const [inline] Returns whether a cache
       is open.

Author

       Generated automatically by Doxygen for Coin from the source code.