Coin: SoWriteAction Class Reference

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SoWriteAction Class Reference
Action Classes

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

`#include <Inventor/actions/SoWriteAction.h>`

Inheritance diagram for SoWriteAction:

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

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

## Protected Member Functions
virtual const SoEnabledElementsList & | getEnabledElements (void) const
virtual void | beginTraversal (SoNode *node)
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 SoEnabledElementsList * | getClassEnabledElements (void)
static SoActionMethodList * | getClassActionMethods (void)
Static Protected Member Functions inherited from SoAction
static SoEnabledElementsList * | getClassEnabledElements (void)
static SoActionMethodList * | getClassActionMethods (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;
}
SbString
The SbString class is a string class with convenience functions for string operations.
Definition SbString.h:52
SbString::getString
const char * getString(void) const
Definition SbString.h:84
SoBase::unref
void unref(void) const
Definition SoBase.cpp:530
SoBase::ref
void ref(void) const
Definition SoBase.cpp:478
SoDB::init
static void init(void)
Definition SoDB.cpp:200
SoGroup::addChild
virtual void addChild(SoNode *node)
Definition SoGroup.cpp:453
SoNode
The SoNode class is the base class for nodes used in scene graphs.
Definition SoNode.h:56
SoOutput
The SoOutput class is an abstraction of an output stream.
Definition SoOutput.h:51
SoOutput::setBuffer
virtual void setBuffer(void *bufPointer, size_t initSize, SoOutputReallocCB *reallocFunc, int32_t offset=0)
Definition SoOutput.cpp:585
SoWriteAction
The SoWriteAction class writes a scene graph to file.
Definition SoWriteAction.h:42

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

## ◆ 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.

## ◆ getClassTypeId()

SoType SoWriteAction::getClassTypeId | ( | void |  | ) |
| static

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

## ◆ 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.

## ◆ 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.

## ◆ getEnabledElements()

const SoEnabledElementsList & SoWriteAction::getEnabledElements | ( | void |  | ) | const
| protectedvirtual

Returns list of enabled elements.

Reimplemented from SoAction.

## ◆ 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.

## ◆ 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.

## ◆ initClass()

void SoWriteAction::initClass | ( | void |  | ) |
| static

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

## ◆ getOutput()

SoOutput * SoWriteAction::getOutput | ( | void |  | ) | const

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

## ◆ 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.

## ◆ 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.

## ◆ 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