On Thu, 18 May 2023 23:00:25 GMT, Sergey Bylokhov <s...@openjdk.org> wrote:
>> Perhaps, this needs additional details. The size of checkbox and radio >> button is 13 as reported by Theme API for the standard DPI of 96. Being a >> prime number, 13 doesn't scale well, there's always fractional part unless >> the scale is whole. Thus, the scaled size never matches. >> >> As the result, `CachedPainter` seems to apply a scale to compensate for that >> — whether we choose ceil or floor. The above formula gives better results. >> >> The entire thing should have been simpler: a `MultiResolutionImage` which >> paints the background according to the scale requested. Yet it proved to be >> not as simple. We're planning to look further into simplifying it if >> possible and, alternatively or in addition to, considering [dynamic layout >> based on graphics >> configuration](https://github.com/openjdk/jdk/pull/13701#discussion_r1187985627) >> as you suggested above. >> >> The current solution may be not perfect but it provides better rendering >> compared to what we have now: *the controls look crisp only on the main >> display*. > > But still why the size on the components are so different? is it really > caused by one "pixel/unit" we requested from the native? So, basically for w,h =19 we calculate a DPI of 140 and Dimension d = getPartSize(getTheme(widget, dpi), part, state); at line 172 of ThemeReader.java call returns a part size of 13 x 13 provided by windows as it is closer to DPI=120 (for 125% scaling). While for w,h =20 we calculate a DPI of 147 and Dimension d = getPartSize(getTheme(widget, dpi), part, state); at line 172 of ThemeReader.java call returns a part size of 20 x 20 provided by windows as it is closer to DPI=144 (for 150% scaling). Thus part size calculated by us and provided by Windows matches and hence we see bigger properly rendered buttons while for the w,h=19 case we have 19x19 , while windows gives 13x13 and hence you see scaled down buttons with bad rendering. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/13701#discussion_r1206133530
