Problem:
Check boxes and radio buttons in Windows Look-and-Feel have rendering issues
when window is moved from display with one scale to display with a different
scale on a multi-monitor setup:
- Scrawly ticks in checkboxes;
- Wrong circle relations in selected radio buttons.
Root-cause:
We open theme on AWT Toolkit Window which always has Primary Monitor DPI.
Due to this when the app window goes to Secondary Screen with different DPI UI
buttons
appear incorrectly rendered.
Following is a list proposed changes to fix this issue.
Proposed Fix with Summary of changes:
1. Open a new Theme Handle per the DPI of the Screen where the App window is.
--> This makes sure we get the correct size for UI buttons based on the DPI of
the screen where the app.
window is.
2. GetPartSize() of icons returns size based on standard size = 96 DPI.
--> This change makes sure that the default size of UI buttons is 96 since we
use this on Java side to layout UI.
3. Rect size for icons in native paintBackground() function is fetched from
Windows that specific DPI.
-->This makes sure that the UI buttons aren't stretched because the size
calculated on Java side is different from what Windows returns. Thus UI
buttons are scaled correctly once we get their size back from Windows.
4. Adjust width and the height of the resolution variant image so that for
scaling values of 1.25 , 2.25 , and such we always floor, while for 1.5,
1.75, 2.5, 2.75 , and such we always ceil.
--> This helps make sure that for .25s scaling we get better rendering.
This is because when we go from Double to Int for pixel rendering we sometimes
need to floor or ceil to get crisp rendering.
As of now with these changes the rendering is crisp and good for all scaling
factors with the exception .25s wherein some small artifact is seen sometimes
in rendering of buttons but is still much better compared to what we have now.
Testing:
Tested locally on my Windows machine with a 2 monitor setup 125%, 150%, 175%,
225% scaling values and on mach5.
___________________________________
Monitor 1 | Monitor 2
(Primary) |
|
125% | 175%
150% | 175%
150% | 225%
175% | 175%
175% | 150%
175% | 225%
_____________________ |_____________
Also tested on setup with scaling values of up-to 350%.
-------------
Commit messages:
- code clean up
- fix for JDK-8294427
Changes: https://git.openjdk.org/jdk/pull/13701/files
Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13701&range=00
Issue: https://bugs.openjdk.org/browse/JDK-8294427
Stats: 132 lines in 4 files changed: 59 ins; 26 del; 47 mod
Patch: https://git.openjdk.org/jdk/pull/13701.diff
Fetch: git fetch https://git.openjdk.org/jdk.git pull/13701/head:pull/13701
PR: https://git.openjdk.org/jdk/pull/13701
