OS Windows, set part of the window semi-transparent

General
1

Hi. In OS Windows I need to set a part of a window semi-trasparent. Example, the right half.
How I can do it?

2

Maybe you check OverlayMBS class to make such a window?
http://www.monkeybreadsoftware.net/pluginpart-overlay.shtml

3

The problem you have is you can only do one of two things in windows, have transparency across the whole window or have a hole cut out of the window/the window shaped how you want. The difficulty is doing both at the same time.

Here’s a nice article on the issue.

https://www.codeproject.com/Articles/34158/Cool-Semi-transparent-and-Shaped-Dialogs-with-Stan

It should be possible in Xojo using declares.