On Mon, 15 Dec 2025 06:18:46 GMT, Michael Strauß <[email protected]> wrote:
>> On Windows, the `Stage.width` and `Stage.height` correspond to the window >> size as returned by `GetWindowRect`. >> >> Up until Windows 10, the size of a window was identical to its visual >> borders. However, since Windows 10 has introduced thin visual window >> borders, the window manager adds an invisible border of a few pixels around >> the window to make it easier to resize the window. Since `GetWindowRect` >> returns the window size _including_ these invisible borders, the location >> and size of a `Stage` isn't exactly what we'd expect. >> >> For example, if we place a `Stage` at `setX(0)` and `setY(0)`, the window >> appears with a small distance from the screen edge, and the window size >> extends a few pixels beyond its visual borders (in the following images, the >> screenshot size corresponds to the window size; note the invisible padding >> around the edges): >> <img width="300" alt="window-size-1" >> src="https://github.com/user-attachments/assets/76ea6861-885f-4bea-aeb7-e8e6464b7199" >> /> >> >> What we actually want is to have the visual borders line up with the edges >> of the screen, and have the window size correspond to the visual borders: >> <img width="295" alt="window-size-2" >> src="https://github.com/user-attachments/assets/ca6bed73-e4e7-4df6-9491-d82792bb0866" >> /> >> >> The implementation is quite simple: instead of `GetWindowRect`, we use >> `DwmGetWindowAttribute(DWMA_EXTENDED_FRAME_BOUNDS)`. This gives us the >> bounds of the visual window borders. If this function fails, we fall back to >> `GetWindowRect` (now, I don't know why >> `DwmGetWindowAttribute(DWMA_EXTENDED_FRAME_BOUNDS)` would ever fail... maybe >> an old Windows version in a remote desktop scenario?). > > Michael Strauß has updated the pull request incrementally with one additional > commit since the last revision: > > handle edge cases I've looked at every call to `GetWindowRect` and, where appropriate, replaced it with `GetExtendedFrameBounds`. In addition to that, I also tested the case when JavaFX is running in a DPI-unaware process. I've added code that detects this situation and applies the correct mapping from physical coordinates into virtualized coordinates. ------------- PR Comment: https://git.openjdk.org/jfx/pull/1982#issuecomment-3653583473
