So lets say I have a struct called 'Sprite.' Inside that struct is the member LPDIRECT3DTEXTURE9 texture.

Let's say I make an array of Sprite's that looks like: Sprite myArray[1000].

I want the same image to be loaded to all 1000 of myArray texture members.

I could make a for loop that uses 'LoadTexture' (My texture loading function) to load an image to each texture member. But this is a very taxing process and takes a noticable amount of time to complete. At the end of my program I would then release() each texture via for loop.

So the other option is to create a LPDIRECT3DTEXTURE9 defaultImage. Load an image to defaultImage, then run a loop that:

myArray.texture = defaultImage;

The load time is unnoticible using this method.

So here's my question:

Do I have to release() all 1000 textures in myArray or do I only have to release() defaultImage?

For the record, I've tried realease()ing all 1000. Get the Unhandled exception at 0x00430906 error and have to break.

Does that mean I'm doing something wrong, or that I only have to release the one? An explination as to why would be nice as well.

Thanks for the help!

As a rule, for every resource Create(), you need a Dispose().

In the second example you create one texture that is shared amongst 1000
objects. This means there's one Texture, but 1000 references to it.
Therefore, you need only 1 Dispose().

In the second example you create one texture that is shared amongst 1000 objects. This means there's one Texture, but 1000 references to it. Therefore, you need only 1 Dispose().

COM objects don't really work that way. Because they're internally reference counted, if anything needs to hold on to the object for any reason, that assignment should be accompanied by an AddRef. Then it can be safely Released later on, which will just decrement the reference count rather than destroying the object. When the final Release happens, the object is destroyed.

The reason for this is that if something else Releases the texture while your myArray (to use the example here) is still using it, the texture won't be destroyed and myArray can continue to safely use it.

So in other words, yes, Release the defaultTexture 1000 times as you currently are, but also add an AddRef when you set them to your myArray, and the Release won't crash, giving you proper COM object lifetimes.

You see this kind of pattern all over the design of D3D; e.g. GetSurfaceLevel will require a Release otherwise the surface leaks, and - more relevant here - ID3DXEffect will AddRef on a SetTexture call.

Thanks for the help! Very informative. I'm new to development so I'll put some time into studying AddRef, as it sounds pretty vital.

But just for the sake of understanding, if I only release defaultImage like in the second example, is that causing a memory leak in myArray? Is it bad/dangerous coding or just improvable coding? (for the record I don't intend on settling for poor coding).

If you're referring to the second example in your original post ("So the other option is to create a LPDIRECT3DTEXTURE9 defaultImage. Load an image to defaultImage, then run a loop that: myArray.texture = defaultImage;") - no, it won't leak. This doesn't actually copy any data at all, so you still only have one copy of the texture. Instead each myArray.texture will point to the original texture (if this concept sounds strange to you then I recommend doing some reading/learning/exercises on pointers).

Where you get trouble is when you Release defaultImage. Each myArray.texture still points to defaultImage, but defaultImage is no longer valid for use. Any operation on myArray.texture will - if you're lucky - crash immediately. If you're unlucky it will continue working then give you weird behaviour (or a crash) some time later and you'll have no idea whatsoever where to even begin looking for the problem. This normally happens the day before a release deadline.

Ah yes! And the reason nothing is copied is because LPDIRECT3DTEXTURE9 is a pointer! I forgot about that. Okay, thanks for taking the time not just to answer, but to help me understand as well.