[Interest] High-dpi fixing for Qt 5.5

[John Weeks]

It looks to me like at present (Qt 5.4) the various devicePixelRatio() functions on Windows only return 1.0 or 2.0. But Windows systems can be at fractional ratios- will 5.5 address that?

It also appears that drawing a QPixmap or QImage with a fractional ratio actually works, but we can't discover that situation easily.

-John Weeks
WaveMetrics, Inc.