Security can also be a factor - hardware overlays could be drawn over any window (even a log on screen).

It initially released on PC, Xbox and PlayStation 2, later followed with additional releases on PlayStation Portable, Xbox 360.

The game is designed as an open world action-adventure around the plot of The Godfather movie.

At that time, the most popular Windows version was Windows XP.

Forced compatibility modes, windowed modes, D3D wrappers - nothing fixes the issue.

However, we have a key to a successful fix - issue is totally reproducible.

All clips in the game are stored as VP6 files, a proprietary format which seemed to have been EAs format of choice for videos in their mid-2000s games.

While this is not relevant for further analysis, a few pieces of information regarding the format specs can be found here.

However, there is one important difference between GF and all those other titles - their VP6 movie players work just fine.

This is actually very good info, since all RW experience I have gained throughout the years of working with GTA III, Vice City and San Andreas could be useful at a later point (spoiler: it was crucial).

These days we have symbols for huge parts of their binaries (thanks to mobile ports leaving them over), so literally any RW function used in Godfather can be indexed and properly named.

Thats where things are getting interesting - its obviously games own code, why would it suddenly stop working on Vista.

Maybe a memory corruption which remained undetected on older systems Or maybe game is exploiting some undocumented feature which got changed in a new OS and code started failing.

Thankfully, its possible to remotely debug the game running on a XP virtual machine - the catch is, the newest Visual Studio working on XP is 2010.

Armed with two separate Visual Studios and stepping through both games, they finally started behaving differently.

You could ask - why is the code skipping only some parts of movie player logic.

Finding an initialization function proved to be fairly easy, and it provided critical information.

The first one is a flag indicating overlay surfaces are supported.

In order for initialization to succeed, both features need to be supported, which means we dont support at least one of those two.

Overlay operation is performed on hardware,and thus such surfaces are efficient for using with high frame rate video content.

Additionally, they can have a format different than the primary surface.

However, I think the main reason they were used in Godfather was their ability to directly display data in non-RGB formats - VP6 movies are decoded to YUY2 format which will be explained in detail later.

The Godfather The Game Windows 10