GetScaleFactorForMonitor changes depending on packaging type

[dalyIsaac]

Describe the bug

I have a monitor with 175% scaling. When <WindowsPackageType>None</WindowsPackageType> is set, the scale factor is incorrectly reported as SCALE_140_PERCENT. When the packaging type is not specified, the scale factor is correctly reported as SCALE_175_PERCENT. The app manifest uses PerMonitorV2 DPI awareness in both cases.

Steps to reproduce the bug

1. Set a secondary monitor as having 175% scaling, with the primary monitor having 100% scaling
2. Create a new WAS unpackaged app
3. For each monitor, call GetScaleFactorForMonitor

Expected behavior

The scale factor will be incorrectly reported as SCALE_140_PERCENT.

Screenshots

No response

NuGet package version

Both of:

• Windows App SDK 1.2.5: 1.2.230313.1
• Windows App SDK 1.3.0: 1.3.230331000

Packaging type

No response

Windows version

Windows 11 version 22H2 (22621, 2022 Update)

IDE

Visual Studio 2022

Additional context

I've made a repo which demonstrates this: https://github.com/dalyIsaac/WindowsMonitorInfo. It renders a list of monitors, their DPIs, resolutions, and scale factors.

[DarranRowe]

Just to ask that question, since GetScaleFactorForMonitor is a Windows API function, do you only see this problem when the Windows App SDK is active in the application or do you see this in any other desktop application?

[dalyIsaac]

In both a console app and a Windows Forms app, the reported scale factor is SCALE_140_PERCENT.

Setting SetThreadDpiAwarenessContext(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2); changes the reported DPI, but does not affect the scaling.

[kpsam2000Intel]

Similar observation! I tried both project settings for per-process DPI awareness as well as SetProcessDpiAwareness(PROCESS_PER_MONITOR_DPI_AWARE). Didn't help. My settings page has 150% as scaling.
I could get 150% using GetDpiForMonitor() once I set PROCESS_PER_MONITOR_DPI_AWARE.
150% is the default as per OS settings page.

If I forcefully change scaling to 125%, GetDpiForMonitor() gives me 125% and GetScaleFactorForMonitor() gives 100%