How to understand the call stack of Visual Studio?

Question

  VCamD.ax!CFactoryTemplate::CreateInstance()  + 0x3f bytes 
> VCamD.ax!CClassFactory::CreateInstance()  + 0x7f bytes 

What's 0x7f and 0x3f?

Answer 1

Those values are the offset of the instruction pointer from the start of the listed function.

It's a way of expressing which assembly instruction is currently being executed in the function. Similar to having the the current source code line highlighted in the editor. Except that the offset is at the assembly level not the source code level.