Hello Carmelo_DrRaw !
Just tested today's new build:
Windows 7 - 64 bit
CPU: Intel I7
Ram: 8 gb
Gpu : Nvidia graphic card
At present, it does NOT crash anymore !
Congratulations for your last improvements
@Carmelo_DrRaw: I have also simplified a bit the code, with the goal of making the tool more responsive... maybe you can give me your impressions.
As usual it is not smooth. You do notice this behaviour when you clone big images.
For example, with jpeg images more than 2 Mb. Generally, it is really a pain...
Needless to say with Nef images you can only clone small parts of your images unless you have a lot ot fime to wait for PhotoFlow procesing your changes...
When you zoom-in or zoom-out, while cloning, it is even much worse.
Sometimes you even have weird results while waiting:
This being said I do not think it is your fault as regards this slowness.
I have tested quite a lot Krita  on Windows.
For starters, they provide 64 bit installers.
The threading stuff is excellent: It was one of the first implementations they did.
In addition, with Krita the canvas (zooming, panning etc) is handled through OpenGL (by way of your graphic card).
On Windows, due to the different file system (NTFS), Krita is slower than on Linux though.
I am not a software developer but I know for sure that usually fine-tuning a programme to improve its speed is by far the most difficult and time-consuming task