Windows 11 rounded corner on HiDPI displays

In Windows 11, HyperSnap captures window with rounded corner, but in scaled mode, e.g., 200% or 250% zoom level, HyperSnap captures the window corner with a smaller radius, thus leaving a rounded edge which consists of:
 
A white corner
+
Background content inside a rounder corner with smaller radius
+
Window content
 
I can't upload the screenshot file directly. Here is the imgbb viewer link:
 
https://ibb.co/Ptz671F
 
Please check, thank you.

The dimensions are well documented. Please take a look at
 
https://docs.microsoft.com/en-us/windows/apps/design/signature-experiences/geometry
 
For example, the value of the radius of the rounded corners of the top-level windows, it is 8 * PPI_Of_Current_Display / 96.
 
An option that switches between a rectangular and a rounded window is a good idea.

I upgraded to 8.20. HyperSnap seems like not DPI-aware and the snapped pictures are the same as before: the rounded corner still contains the background color.
 
The screenshot: https://ibb.co/Vw1v3pQ
 

The screenshot is about the DPI-awareness: you can see the resolution of the background program (the chessboard, the pieces and the texts on the ribbon bar are all sharp) and HyperSnap's buttons and texts are coarse.
 
In 8.19 HyperSnap's interface is fine.

Windows 11's renderer blends the window border with the background content, I think there are two options to get the accurate window bitmap:
 
1. Use DwmSetWindowAttribute API to prevent the window be rounded.
 
https://docs.microsoft.com/en-us/windows/win32/api/dwmapi/nf-dwmapi-dwmsetwindowattribute
 
This is the best option IMO.
 
2. Create a pure white borderless window just under the window to capture to prevent any bitmap blending. This will leave a gray rounded margin outside the window rounded corner: the alpha mask layer, see the screenshot.
 
https://ibb.co/NY2mVGN
 
A pure black background seems to have better effect
 
https://ibb.co/mNnB8Tm
 
but there are several white pixels on the top-left corner, I think it is a HyperSnap bug: the flashing rectangle remains some pixels there.

I have tried 8.20.01 and found two problems.
 
1. I misunderstood the geometry guide (sorry for that), the radius is by the number of physical pixels, not logical, so it shouldn't be multiplied by current DPI then divided by 96.
 
The outer frame of the captured window seems one or two pixels smaller than the actual size. As you can see, the left border of the Notepad window is missing, and other borders are thinner than they actually are.
 
https://ibb.co/Qbqq2nf
 
2. After several window captures, HyperSnap always captures all-white window content. I guess the white background window is put on the top of the window to capture by mistake.
 
https://ibb.co/86TbRKx

> I deliberately omit this border, as it is not a solid color, but partially transparent, so it captures random pixels of the background. It did not look right to me.
 
That will lose the left border. See the picture.
 
https://ibb.co/p4NhPnP
 
A Notepad window on a pure-white background doesn't have random pixels on the corners. Because of the anti-aliasing processing, they are not pure color.
 
https://ibb.co/mR0q6Yt
 
> Which capture operation do you use when you get all-white content, exactly? Which hotkey or which capture button do you press to reproduce this
 
I forgot to mention that only happened when the target window belongs to processes ran from Administrator. The 'Snipping Tool' comes with Windows 11 can capture the content of the windows of such type without problems.

This adjustment for window captures is now available in HyperSnap 8.21 (or any later) found on this site.
 
Greg

Thank you, I made a small correction to check for rounded corners or not, but can't test it on RegEx Buddy, they don't have a free trial. I did not update the version number for this small change, if you want, download ver. 8.21 again, install on top of your current one and test. Thank you for your help!
 
Greg

Thank you, the About window of this app indeed has no rounded corners. At this time I don't know how I could discover this fact programmatically and change the capture shape. Will investigate, if time permits.