Releasing memory with AIS_InteractiveContext::Remove() and Nullify()

Hi everybody,

I'm having problems with the function Remove() of an Interactive Context. In my application I create a new AIS_Shape using the new operator and storing it for later use in a Handle(AIS_Shape). After that the refernce counter of the handle is 1. After displaying the object in my AIS_InteractiveContext using the Display() function the reference counter is increased to 3. After some operations I want to free the allocated memory for the AIS_Shape object again. This is done I think using the Remove function. Then I force the release of the handle by calling the Nullify() function of the Handle(AIS_Shape), which first decrements the reference counter by one and then checks whether the counter is 0. But it is not 0, during debugging I found that calling Remove() decreases the reference counter only by 1 from 3 to 2, so that the later call of Nullify results in a reference counter of 1. Because of this the memory is not released. It seems to me that somehow the Interactice Context still owns a reference to my handle.

So my questions is am I doing somthing wrong, or is there any other way to force the release of memory of an interactive object.

Thanks for your help,

Sven Jungnickel

n-southall's picture

Hi Sven,

Well, this won't be any help to you at all I'm afraid, but after I saw your question I checked the behaviour of the reference counters for objects I am calling Remove() on. I found that the reference counter drops from 3 to 1 after calling Remove(). i.e. it is working correctly. I would say that you are not doing something wrong, and maybe something odd is happening in your code. I haven't updated to OCC 5.1 yet, I'm still on 5.0. Which version are you using?



Sven Jungnickel's picture

Hi Neil,

I'm also on version 5.0 and I don't have a clue what's the reason for this behaviour. The reason I do all the stuff is that my AIS_Shape object is recalculated and I want to discard the old one before assigning the new object. Maybe the AIS_Shape::Set() function automatically does this, but I can only find the function prototype...I'm still searching the source for this function...

But thanks for your answer. Now I know that normally it is the correct way.


Ivan's picture

Hi everybody,

Ivan's picture

It seems to me I've got the same behavior on 6.2 version. What's to do?
Thanks, Ivan.

Ivan's picture

Well, I found the solution here:
Many thanks to Sangsu Lee, it works fine.
Best regards, Ivan.