Game Object Factory: Fixing Memory Leaks
- by Bunkai.Satori
Dear all, this is going to be tough: I have created a game object factory that generates objects of my wish. However, I get memory leaks which I can not fix.
Memory leaks are generated by return new Object(); in the bottom part of the code sample.
static BaseObject * CreateObjectFunc()
{
return new Object();
}
How and where to delete the pointers? I wrote bool ReleaseClassType(). Despite the factory works well, ReleaseClassType() does not fix memory leaks.
bool ReleaseClassTypes()
{
unsigned int nRecordCount = vFactories.size();
for (unsigned int nLoop = 0; nLoop < nRecordCount; nLoop++ )
{
// if the object exists in the container and is valid, then render it
if( vFactories[nLoop] != NULL)
delete vFactories[nLoop]();
}
return true;
}
Before taking a look at the code below, let me help you in that my CGameObjectFactory creates pointers to functions creating particular object type. The pointers are stored within vFactories vector container.
I have chosen this way because I parse an object map file. I have object type IDs (integer values) which I need to translate them into real objects. Because I have over 100 different object data types, I wished to avoid continuously traversing very long Switch() statement.
Therefore, to create an object, I call vFactoriesnEnumObjectTypeID via CGameObjectFactory::create() to call stored function that generates desired object.
The position of the appropriate function in the vFactories is identical to the nObjectTypeID, so I can use indexing to access the function.
So the question remains, how to proceed with garbage collection and avoid reported memory leaks?
#ifndef GAMEOBJECTFACTORY_H_UNIPIXELS
#define GAMEOBJECTFACTORY_H_UNIPIXELS
//#include "MemoryManager.h"
#include <vector>
template <typename BaseObject>
class CGameObjectFactory
{
public:
// cleanup and release registered object data types
bool ReleaseClassTypes()
{
unsigned int nRecordCount = vFactories.size();
for (unsigned int nLoop = 0; nLoop < nRecordCount; nLoop++ )
{
// if the object exists in the container and is valid, then render it
if( vFactories[nLoop] != NULL)
delete vFactories[nLoop]();
}
return true;
}
// register new object data type
template <typename Object>
bool RegisterClassType(unsigned int nObjectIDParam )
{
if(vFactories.size() < nObjectIDParam) vFactories.resize(nObjectIDParam);
vFactories[nObjectIDParam] = &CreateObjectFunc<Object>;
return true;
}
// create new object by calling the pointer to the appropriate type function
BaseObject* create(unsigned int nObjectIDParam) const
{
return vFactories[nObjectIDParam]();
}
// resize the vector array containing pointers to function calls
bool resize(unsigned int nSizeParam)
{
vFactories.resize(nSizeParam);
return true;
}
private:
//DECLARE_HEAP;
template <typename Object>
static BaseObject * CreateObjectFunc()
{
return new Object();
}
typedef BaseObject*(*factory)();
std::vector<factory> vFactories;
};
//DEFINE_HEAP_T(CGameObjectFactory, "Game Object Factory");
#endif // GAMEOBJECTFACTORY_H_UNIPIXELS
