7 replies to this topic

[Deortuka]

I recently had an idea to wrap my DX11 resource pointers (ID3D11Buffer*, ID3D11RasterizerState*, etc...) so that Release would automatically be called once they are deleted from the vector that I use to save all created resources.

 

I then had the idea to check out STL to see if shared_ptr would provide the necessary functionality. So far it seems all I have to do is add a custom deleter function that calls Release().

 

I wanted to know if anyone has tried this approach before. If so, does it work as expected?

 

Thanks in advance.

[chetanjags]

Hi, I think maybe you are looking for ComPtr already provided by microsoft http://msdn.microsoft.com/en-us/library/br244983.aspx

[turch]

As Chetanhl said, use ComPtr

 

http://legalizeadulthood.wordpress.com/2009/01/11/direct3d-programming-tip-3-use-smart-pointers/

[Deortuka]

Thanks a lot for the replies. Unfortunately, I am still left curious as to why the use of CComPtr in Direct3D programming is not recommended in the D3D documentation nor samples.

[ray_intellect]

Perhaps you could use Java instead and automatically release all your textures without any extra code 

[Jason Z]

Perhaps you could use Java instead and automatically release all your textures without any extra code 

Ummm - I don't think you can use Direct3D with Java and just 'automatically release all your textures without any extra code'.  Regardless of what programming language you use, Direct3D is a COM based interface.  You have to use the COM methodology regardless of the reference counting scheme - either garbage collection in Java or smart pointers/ComPtr in C++.

[phil_t]

Perhaps you could use Java instead and automatically release all your textures without any extra code

Automatic memory management doesn't eliminate the need to manage native resources like graphic devices, textures, etc..

When you release a texture, you usually want it to be gone from memory immediately, not "some time later". So you end up having to write extra code (e.g. disposable pattern) in managed environments too.

Edited by phil_t, 20 March 2013 - 03:58 PM.

[SiCrane]

Unfortunately, I am still left curious as to why the use of CComPtr in Direct3D programming is not recommended in the D3D documentation nor samples.

For the most part the DirectX samples assume that you are already familiar with COM. Things like smart pointers are mentioned in Microsoft's COM coding guides.

And yes, people have tried using shared_ptr with COM interfaces. However, it does work slightly weirdly. Since shared_ptr uses an external reference count in addition to the COM internal reference count, weak_ptr doesn't know if there are still non-shared_ptr references keeping an object alive that the shared_ptr group doesn't know about, so the object will look deleted to a weak_ptr when it's actually still alive.