Memory allocate in Ogre

标签：ogre   c++   memory   new   

Memory allocate in Oger

Memory allocate

Every memory in ogre will be allocated from AllocatedObject, it use Policy to switch from different allocators.

It looks like this:

template <class Alloc> class _OgreExport AllocatedObject
{
	public:
		void* operator new(size_t sz, const char* file, int line, const char* func)
		{
			return Alloc::allocateBytes(sz, file, line, func);
		}
		void* operator new(size_t sz)
		{
			return Alloc::allocateBytes(sz);
		}
		/// placement operator new
		void* operator new(size_t sz, void* ptr)
		{
			(void) sz;
			return ptr;
		}
		/// array operator new, with debug line info
		void* operator new[] ( size_t sz, const char* file, int line, const char* func )
		{
			return Alloc::allocateBytes(sz, file, line, func);
		}
		void* operator new[] ( size_t sz )
		{
			return Alloc::allocateBytes(sz);
		}
		.....
		..override delete
		.....
}

There are 3 predefined memory allocator  policies and 1 custom memory allocator in ogre.

#define OGRE_MEMORY_ALLOCATOR_NEDPOOLING 4

By default ogre use OGRE_MEMORY_ALLOCATOR_NEDPOOLING, STD is legacy,

If you are interested, you can read the ned allocation policy here. 

For most user, you just need to know how to use it.

#elif OGRE_MEMORY_ALLOCATOR == OGRE_MEMORY_ALLOCATOR_NED
#  include "OgreMemoryNedAlloc.h"
namespace Ogre
{
	template <MemoryCategory Cat> class CategorisedAllocPolicy : public NedAllocPolicy{};
	template <MemoryCategory Cat, size_t align = 0> class CategorisedAlignAllocPolicy : public NedAlignedAllocPolicy<align>{};
}
#elif

enum MemoryCategory
	{
		/// General purpose
		MEMCATEGORY_GENERAL = 0,
		/// Geometry held in main memory
		MEMCATEGORY_GEOMETRY = 1, 
		/// Animation data like tracks, bone matrices
		MEMCATEGORY_ANIMATION = 2, 
		/// Nodes, control data
		MEMCATEGORY_SCENE_CONTROL = 3,
		/// Scene object instances
		MEMCATEGORY_SCENE_OBJECTS = 4,
		/// Other resources
		MEMCATEGORY_RESOURCE = 5,
		/// Scripting
		MEMCATEGORY_SCRIPTING = 6,
		/// Rendersystem structures
		MEMCATEGORY_RENDERSYS = 7,

		
		// sentinel value, do not use 
		MEMCATEGORY_COUNT = 8
	};

typedef CategorisedAllocPolicy<Ogre::MEMCATEGORY_SCENE_OBJECTS> SceneObjAllocPolicy;
typedef AllocatedObject<SceneObjAllocPolicy> SceneObjAllocatedObject;
typedef SceneObjAllocatedObject		MovableAlloc;

class  MovableObject : <span style="font-family: Arial, Helvetica, sans-serif;">MovableAlloc</span>

OGRE_NEW_T(T, category) new (::Ogre::CategorisedAllocPolicy<category>::allocateBytes(sizeof(T))) T

Memory allocate in Ogre

标签：ogre   c++   memory   new   

原文地址：http://blog.csdn.net/peanutandchestnut/article/details/42607683