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/*
* Modification History
*
* 2001-March-14 Jason Rohrer
* Created.
*
* 2001-April-1 Jason Rohrer
* Added subreal entity vane class to factory.
*/
#ifndef PRIMITIVE_3D_FACTORY_INCLUDED
#define PRIMITIVE_3D_FACTORY_INCLUDED
#include "Primitive3D.h"
// Run-time type identification interface (RTTI)
#include <typeinfo>
// include these primitives only if we are part of subreal
#ifdef SUBREAL
#include "subreal/entity/EntityBodyPrimitive3D.h"
#define FACTORY_ENTITY_BODY_PRIMITIVE_FLAG 1
#include "subreal/entity/EntityVanePrimitive3D.h"
#define FACTORY_ENTITY_VANE_PRIMITIVE_FLAG 2
#endif
// the default flag
#define FACTORY_DEFAULT_PRIMITIVE_FLAG 0
/**
* Class that maps Primitive3D integer subclass type flags to Primitive3D
* subclass instances.
*
* Motivation for this class:
* We want to extend Object3D to support subclass typed serialization
* and deserialization without placing too much of a burden on
* future Object3D subclasses. For instance, we don't want subclasses
* to have to write their own de/serialization functions so that
* particular Primitive3D subclasses are serialized correctly.
* We can avoid this burden by writing the base Object3D serialization
* code so that it uses this factory to transmit subclasses with
* type informaton.
*
* @author Jason Rohrer
*/
class Primitive3DFactory {
public:
/**
* Finds an integer subclass type flag for a primitive instance.
*
* @param inPrimitive the primitive to determine a flag for. Must
* be destroyed by the caller.
*
* @return a type flag for inObject. 0 (the default Object3D
* baseclass flag) will be returned if subclass determination fails.
*/
static int primitive3DToInt( Primitive3D *inPrimitive );
/**
* Constructs a new, unitialized Primitive3D (in other words,
* an Primitive3D ready for deserialization) of a subclass
* type matching inTypeFlag.
*
* @param inTypeFlag the type flag specifying the class
* of the returned primitive.
*
* @return an (unitialized) Primitive3D class instance with a
* subclass type corresponding to inTypeFlag. If no
* matching class is found, a default Primitive3D baseclass
* instance is returned. Must be destroyed by the caller.
*/
static Primitive3D *intToPrimitive3D( int inTypeFlag );
};
inline int Primitive3DFactory::primitive3DToInt( Primitive3D *inPrimitive ) {
// use RTTI to determine type of inPrimitive
#ifdef SUBREAL
if( typeid( *inPrimitive ) == typeid( EntityBodyPrimitive3D ) ) {
return FACTORY_ENTITY_BODY_PRIMITIVE_FLAG;
}
else if( typeid( *inPrimitive ) == typeid( EntityVanePrimitive3D ) ) {
return FACTORY_ENTITY_VANE_PRIMITIVE_FLAG;
}
#endif
// else return the default flag
return FACTORY_DEFAULT_PRIMITIVE_FLAG;
}
inline Primitive3D *Primitive3DFactory::intToPrimitive3D( int inTypeFlag ) {
switch( inTypeFlag ) {
case FACTORY_DEFAULT_PRIMITIVE_FLAG:
return new Primitive3D();
break;
/* these primitives are only defined if
* we are part of subreal
*/
#ifdef SUBREAL
case FACTORY_ENTITY_BODY_PRIMITIVE_FLAG:
return new EntityBodyPrimitive3D();
break;
case FACTORY_ENTITY_VANE_PRIMITIVE_FLAG:
return new EntityVanePrimitive3D();
break;
#endif
default:
// unknown primitive flag type
return new Primitive3D();
break;
}
}
#endif
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