Attribute Interface for merging attribute data between details. More...

#include <GA_AIFMerge.h>

Public Member Functions
	GA_AIFMerge ()

virtual	~GA_AIFMerge ()

virtual void	destroyDestination (const GA_MergeMap &map, GA_Attribute *dattrib, const GA_Attribute &sattrib) const =0

virtual GA_Attribute *	addDestination (const GA_MergeMap &map, GA_Attribute *dattrib, const GA_Attribute &sattrib) const =0

virtual void	growArray (const GA_MergeMap &map, GA_Attribute &dattrib, const GA_Attribute *sattrib) const

virtual bool	copyArray (const GA_MergeMap &map, GA_Attribute &dattrib, const GA_Attribute *sattrib) const =0

Static Public Member Functions
static bool	destroyMismatchedType (const GA_MergeMap &map, GA_Attribute *dest)

static GA_Attribute *	addMismatchedType (const GA_MergeMap &map, GA_Attribute *dest, const GA_Attribute &src)

static bool	checkTupleStorage (const GA_MergeMap &map, GA_Attribute &dest, const GA_Attribute &src)

static bool	checkTupleSize (const GA_MergeMap &map, GA_Attribute &dest, const GA_Attribute &src)

Detailed Description

Attribute Interface for merging attribute data between details.

This class provides an interface used to copy attribute data from one detail to another detail. The source detail is const and contains the geometry which will be merged into the destination detail.

Merging is done in stages:

Initially, the attributes on the source detail (the one being merged into the destination) are iterated over and if there's a matching "destination" attribute, the destroyDestination() method is called.
This gives the merging interface a chance to destroy any attributes on the destination (depending on the options in the GA_MergeMap). The method will be called once for each attribute on the source detail.
This provides the opportunity to delete attributes on the detail prior to the re-allocation of attribute arrays.

If map.getMergeStrategy() is not GA_MergeOptions::MERGE_INTERLEAVE, then, the growArray() method is called. By default, this will simply call GA_Attribute::setArraySize() with the new size. However, this method provides the opportunity to perform optimizations in copying data from the source.

After the destination arrays have been resized to accommodate new elements, (or modify) attributes on the destination attribute, the addDestination() method will be called to create new attributes on the desintion detail. The method will be called for each attribute on the source detail.

The last stage of a merge is the copyArray() method. At this point, the attribute should have all the storage allocated and it should be as simple as using the source and destination iterators to copy the data. If optimizations are made in the growArray() method, you will most likely have to alter behaviour based on the map.getMergeStrategy().

Definition at line 56 of file GA_AIFMerge.h.

Constructor & Destructor Documentation

GA_AIFMerge::GA_AIFMerge ( )

virtual GA_AIFMerge::~GA_AIFMerge ( )

virtual

Member Function Documentation

virtual GA_Attribute* GA_AIFMerge::addDestination	(	const GA_MergeMap &	map,
		GA_Attribute *	dattrib,
		const GA_Attribute &	sattrib
	)		const

pure virtual

The addDestination() method is used to either create or modify attributes on the destination. For example, this method can be used to change storage, tuple size, etc. on an attribute, or to create an entirely new attribute. The dattrib parameter will be set to point to an existing attribute on the destination detail.

Parameters

map	The merge options
dattrib	NULL or the existing destination attribute
sattrib	The source attribute

static GA_Attribute* GA_AIFMerge::addMismatchedType	(	const GA_MergeMap &	map,
		GA_Attribute *	dest,
		const GA_Attribute &	src
	)

static

The addMismatchedType() function is a convenience function to use the options in GA_MergeMap to handle attributes of different types. There are three possible types of return values:

The original mis-matched attribute. This will happen if the dest attribute passed in is a different type than the source attribute, but the merge options specify to keep the original attribute.
A new attribute of the same type as the source. This should only really happen if the dest parameter was NULL.
A NULL pointer. This will happen if it wasn't possible to call clone() on the source attribute.

The method should only be called if the dest and src attributes are different.

This should only be called from within addDestination()

GA_Attribute *
ExampleMergeAIF::addDestination(GA_MergeMap &map, GA_Attribute *dest, const GA_Attribute &s) const {
  Example *da = dynamic_cast<Example *>(dest);
  if (!da)
  {
      dest = GA_AIFMerge::addMismatchedType(map, dest, s);
      da = dynamic_cast<Example *>(dest);
      return da;
  }
  return da;
}

Note: It's possible for dest to be NULL.

Parameters

map	The merge options
dest	NULL or the existing destination attribute
src	The source attribute

See Also: GA_MergeOptions

static bool GA_AIFMerge::checkTupleSize	(	const GA_MergeMap &	map,
		GA_Attribute &	dest,
		const GA_Attribute &	src
	)

static

Convenience function to deal with changing tuple storage (based on merging strategy). The function returns true if the tuple sizes match, false if there's an irreconcilable difference. This should be called from within addDestination(). If the function returns false, then no attribute should be returned from addDestination() (indicating no merging).

Parameters

map	The merge options
dest	The existing destination attribute
src	The source attribute

See Also: GA_MergeOptions

static bool GA_AIFMerge::checkTupleStorage	(	const GA_MergeMap &	map,
		GA_Attribute &	dest,
		const GA_Attribute &	src
	)

static

Convenience function to deal with changing tuple sizes (based on merging strategy) The function returns true if the tuple storage match, false if there's an irreconcilable difference. This should be called from within addDestination(). If the function returns false, then no attribute should be returned from addDestination() (indicating no merging).

Parameters

map	The merge options
dest	The existing destination attribute
src	The source attribute

See Also: GA_MergeOptions

virtual bool GA_AIFMerge::copyArray	(	const GA_MergeMap &	map,
		GA_Attribute &	dattrib,
		const GA_Attribute *	sattrib
	)		const

pure virtual

The copyArray() method is responsible for copying the data from the source to the destination attribute. The GA_MergeMap provides all the information necessary for mapping the source data to the destination.

Note: The destination attribute's AIFMerge is used, and it's possible that the source attribute is NULL (indicating that there's no data to copy).

bool
Example::mergeAppend(GA_MergeMap &map, const GA_Attribute *src)
{
    if (src) {
       // Copy data from the src array to my array
       const GA_Range     &di = map.getDestIterator(getOwner());
       const GA_Range     &si = map.getSourceIterator(getOwner());
       copyArray(*this, di, src, si);
    }
}
bool
ExampleMergeAIF::copyArray(GA_MergeMap &map, GA_Attribute &d, const GA_Attribute *s) const {
  Example *da = dynamic_cast<Example *>(&d);
  if (da)
      da->mergeAppend(map, s);
}

Parameters

map	The merge options
dattrib	NULL or the existing destination attribute
sattrib	The source attribute

virtual void GA_AIFMerge::destroyDestination	(	const GA_MergeMap &	map,
		GA_Attribute *	dattrib,
		const GA_Attribute &	sattrib
	)		const

pure virtual

The destroyDestination() method is used to delete attributes on the destination (dattrib). These are attributes which will not survive the merge.

Parameters

map	The merge options
dattrib	NULL or the existing destination attribute
sattrib	The source attribute

static bool GA_AIFMerge::destroyMismatchedType	(	const GA_MergeMap &	map,
		GA_Attribute *	dest
	)

static

The destroyMismatchedType() function is a convenience function to use the options in GA_MergeMap to handle attributes of different types.

The method should only be called if the dest and src attributes are different.

This should only be called from within destroyDestination()

void
ExampleMergeAIF::destroyDestination(GA_MergeMap &map, GA_Attribute *dest, const GA_Attribute &s) const {
  Example *da = dynamic_cast<Example *>(dest);
  if (!da)
      GA_AIFMerge::destroyMismatchedType(map, dest, s);
}

Note: It's possible for dest to be NULL.

Parameters

map	The merge options
dest	NULL or the existing destination attribute

See Also: GA_MergeOptions

virtual void GA_AIFMerge::growArray	(	const GA_MergeMap &	map,
		GA_Attribute &	dattrib,
		const GA_Attribute *	sattrib
	)		const

virtual

The growArray() method is responsible for growing the array. The default behaviour is to call GA_Attribute::setArraySize(). This method is only called if the merge strategy is not set to GA_MergeOptions::MERGE_INTERLEAVE. It may be possible to perform optimizations depending on how data is stored.

Parameters

map	The merge options
dattrib	NULL or the existing destination attribute
sattrib	The source attribute

The default behaviour is to call:

dattrib.setArraySize( map.getDestCapacity(dattrib.getOwner()) );

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

GA/GA_AIFMerge.h

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation