SoWriteAction Class Reference

The SoWriteAction class writes a scene graph to file. More...

#include <Inventor/actions/SoWriteAction.h>

Inheritance diagram for SoWriteAction:

Public Member Functions
	SoWriteAction (SoOutput *out)
	SoWriteAction (void)
virtual	~SoWriteAction (void)
void	continueToApply (SoNode *node)
void	continueToApply (SoPath *path)
SoOutput *	getOutput (void) const
virtual SoType	getTypeId (void) const
Public Member Functions inherited from SoAction
virtual	~SoAction (void)
virtual void	apply (const SoPathList &pathlist, SbBool obeysrules=FALSE)
void	apply (SoAction *beingApplied)
virtual void	apply (SoNode *root)
virtual void	apply (SoPath *path)
const SoPath *	getCurPath (void)
PathCode	getCurPathCode (void) const
virtual SoNode *	getCurPathTail (void)
SoNode *	getNodeAppliedTo (void) const
const SoPathList *	getOriginalPathListAppliedTo (void) const
SoPath *	getPathAppliedTo (void) const
PathCode	getPathCode (int &numindices, const int *&indices)
const SoPathList *	getPathListAppliedTo (void) const
SoState *	getState (void) const
AppliedCode	getWhatAppliedTo (void) const
SbBool	hasTerminated (void) const
virtual void	invalidateState (void)
SbBool	isLastPathListAppliedTo (void) const
virtual SbBool	isOfType (SoType type) const
void	popCurPath (const PathCode prevpathcode)
void	popCurPath (void)
void	popPushCurPath (const int childindex, SoNode *node=NULL)
void	pushCurPath (const int childindex, SoNode *node=NULL)
void	pushCurPath (void)
void	switchToNodeTraversal (SoNode *node)
void	switchToPathTraversal (SoPath *path)
void	traverse (SoNode *const node)
void	usePathCode (int &numindices, const int *&indices)

Static Public Member Functions
static void	addMethod (const SoType type, SoActionMethod method)
static void	enableElement (const SoType type, const int stackindex)
static SoType	getClassTypeId (void)
static void	initClass (void)
Static Public Member Functions inherited from SoAction
static SoType	getClassTypeId (void)
static void	initClass (void)
static void	initClasses (void)
static void	nullAction (SoAction *action, SoNode *node)

Protected Member Functions
virtual void	beginTraversal (SoNode *node)
virtual const SoEnabledElementsList &	getEnabledElements (void) const
virtual SbBool	shouldCompactPathLists (void) const
Protected Member Functions inherited from SoAction
	SoAction (void)
virtual void	endTraversal (SoNode *node)
void	setTerminated (const SbBool flag)
virtual SbBool	shouldCompactPathList (void) const

Static Protected Member Functions
static SoActionMethodList *	getClassActionMethods (void)
static SoEnabledElementsList *	getClassEnabledElements (void)
Static Protected Member Functions inherited from SoAction
static SoActionMethodList *	getClassActionMethods (void)
static SoEnabledElementsList *	getClassEnabledElements (void)

Additional Inherited Members
Public Types inherited from SoAction
enum	AppliedCode { NODE = 0 , PATH = 1 , PATH_LIST = 2 }
enum	PathCode { NO_PATH = 0 , IN_PATH = 1 , BELOW_PATH = 2 , OFF_PATH = 3 }
Protected Attributes inherited from SoAction
SoState *	state
SoActionMethodList *	traversalMethods

Detailed Description

The SoWriteAction class writes a scene graph to file.

When applied to a scene, this action writes its contents to the stream contained within an SoOutput instance. This can be a file, a memory buffer or a system file handle like stdout, for instance.

All information considered part of the scene graph should be written out, including not only nodes, but also the nodes' field values, global fields (at least those with connections inside the scene the action is applied to), engines in the scene, paths, etc.

The scene is written in the Open Inventor file format. Files in this format can be parsed into their scene graph structures by using the SoDB::readAll() method (SoDB also contains a few other import methods you can use).

Here's a complete, standalone usage example which shows how to write a scene graph to a memory buffer:

#include <Inventor/SoDB.h>
#include <Inventor/actions/SoWriteAction.h>
#include <Inventor/nodes/SoCone.h>
#include <Inventor/nodes/SoSeparator.h>
 
static char * buffer;
static size_t buffer_size = 0;
 
static void *
buffer_realloc(void * bufptr, size_t size)
{
  buffer = (char *)realloc(bufptr, size);
  buffer_size = size;
  return buffer;
}
 
static SbString
buffer_writeaction(SoNode * root)
{
  SoOutput out;
  buffer = (char *)malloc(1024);
  buffer_size = 1024;
  out.setBuffer(buffer, buffer_size, buffer_realloc);
 
  SoWriteAction wa(&out);
  wa.apply(root);
 
  SbString s(buffer);
  free(buffer);
  return s;
}
 
int
main(int argc, char ** argv)
{
  SoDB::init();
 
  SoSeparator * root = new SoSeparator;
  root->ref();
 
  root->addChild(new SoCone);
 
  SbString s = buffer_writeaction(root);
  (void)fprintf(stdout, "%s\n", s.getString());
 
  root->unref();
  return 0;
}

See also

SoOutput

Constructor & Destructor Documentation

SoWriteAction() [1/2]

SoWriteAction::SoWriteAction

(

void

)

Default constructor. Output will be written to stdout in ASCII format.

SoWriteAction() [2/2]

SoWriteAction::SoWriteAction

(

SoOutput *

out

)

Constructor. Output will be written via the out object.

~SoWriteAction()

SoWriteAction::~SoWriteAction ( void )

virtual

Destructor.

Member Function Documentation

addMethod()

void SoWriteAction::addMethod ( const SoType type, SoActionMethod method )

static

This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.

beginTraversal()

void SoWriteAction::beginTraversal ( SoNode * node )

protectedvirtual

This virtual method is called from SoAction::apply(), and is the entry point for the actual scene graph traversal.

It can be overridden to initialize the action at traversal start, for specific initializations in the action subclasses inheriting SoAction.

Default method just calls traverse(), which any overridden implementation of the method must do too (or call SoAction::beginTraversal()) to trigger the scene graph traversal.

Reimplemented from SoAction.

continueToApply() [1/2]

void SoWriteAction::continueToApply

(

SoNode *

node

)

Applies the write method to the subgraph starting at node with the current SoOutput instance, without resetting any of the internal state of the action instance.

This should normally be for internal use only.

continueToApply() [2/2]

void SoWriteAction::continueToApply

(

SoPath *

path

)

Applies the write method to path with the current SoOutput instance, without resetting any of the internal state of the action instance.

This should normally be for internal use only.

enableElement()

void SoWriteAction::enableElement ( const SoType type, const int stackindex )

static

This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.

getClassActionMethods()

SoActionMethodList * SoWriteAction::getClassActionMethods ( void )

staticprotected

Returns list of action methods for this class. The enabledElements and methods variables are protected in the original OIV API. This is not such a good idea, since exposed static class member variables is a major grievance with regard to Win32 DLLs. This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

getClassEnabledElements()

SoEnabledElementsList * SoWriteAction::getClassEnabledElements ( void )

staticprotected

Returns list of enabled elements for this class. The enabledElements and methods variables are protected in the original OIV API. This is not such a good idea, since exposed static class member variables is a major grievance with regard to Win32 DLLs. This function is an extension for Coin, and it is not available in the original SGI Open Inventor v2.1 API.

getClassTypeId()

SoType SoWriteAction::getClassTypeId ( void )

static

This static method returns the SoType object associated with objects of this class.

getEnabledElements()

const SoEnabledElementsList & SoWriteAction::getEnabledElements ( void ) const

protectedvirtual

Returns list of enabled elements.

Reimplemented from SoAction.

getOutput()

SoOutput * SoWriteAction::getOutput

(

void

)

const

Returns a pointer to the SoOutput object we're using when writing the scene graph.

getTypeId()

SoType SoWriteAction::getTypeId ( void ) const

virtual

Returns the type identification of an object derived from a class inheriting SoAction. This is used for runtime type checking and "downward" casting.

Implements SoAction.

initClass()

void SoWriteAction::initClass ( void )

static

Initializes the runtime type system for this class, and sets up the enabled elements and action method list.

shouldCompactPathLists()

SbBool SoWriteAction::shouldCompactPathLists ( void ) const

protectedvirtual

This API member is considered internal to the library, as it is not likely to be of interest to the application programmer.

Compact path lists are not implemented in Coin (yet), but if they are, SoWriteAction should return FALSE here – it would only be extra overhead for the SoWriteAction to have path lists compacted before traversal.

Seems like a silly optimization to me, though.. :^/ 20000306 mortene.

---

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

• SoWriteAction.h
• SoWriteAction.cpp