Improve HiDPI Support for Multi-Monitor Environments

[HeikoKlare]

Current Behavior

In Windows 10/11, using multiple monitors with different DPI settings / scale factors, Eclipse does not adapt to DPI settings of the current monitor when moving the window between different monitors in most cases.
This behavior is also documentation in an SWT issue: eclipse-platform/eclipse.platform.swt#62

Expected Behavior

When moving an Eclipse window between monitors, it should always adapt the DPI settings to the monitor it is currently placed on.

The approach to probably start with is documented here: eclipse-platform/eclipse.platform.swt#131

Process

I see some incremental step to achieve a proper high DPI, multi-monitor support for WIndows:

1. When moving around a workbench window, adapt the scale factor to the monitor the window is currently placed on (> 50% of the window), like it is done when starting the workbench on that monitor.
2. When changing the scale factor of the monitor a workbench window is currently placed on, adapt the scaling of that window, i.e., react to system events that propagate such a change (if existing)
3. (probably platform-independent) Adapt the workbench window scaling to every monitor rather than the one it is mostly placed on. Idea to do so: Split up the graphics contexts of each control into one area per monitor and render the control for each monitor with the according scale factor. For every item to be rendered in the control, it should be able to validate whether part of it is placed on the monitor the rendering is currently performed for.

• Add font registry to SWT #35
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• ...