On Sun, 28 May 2023 22:23:27 GMT, Rajat Mahajan <rmaha...@openjdk.org> wrote:
>> 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%.
>
> Rajat Mahajan has updated the pull request incrementally with one additional
> commit since the last revision:
>
> changes as siggested in review
Changes requested by aivanov (Reviewer).
src/java.desktop/windows/classes/sun/awt/windows/ThemeReader.java line 124:
> 122: if (!valid) {
> 123: // Close old themes.
> 124: if (!dpiAwareWidgetToTheme.isEmpty()) {
The `!isEmpty()` seems redundant. If the map is empty, `values()` returns empty
set; iterating over empty set does nothing.
src/java.desktop/windows/classes/sun/awt/windows/ThemeReader.java line 131:
> 129: }
> 130: dpiAwareWidgetToTheme.get(dpi).clear();
> 131: dpiAwareWidgetToTheme.clear();
Suggestion:
for (Map<String, Long> dpiVal :
dpiAwareWidgetToTheme.values()) {
for (Long value : dpiVal.values()) {
closeTheme(value);
}
dpiVal.clear();
}
dpiAwareWidgetToTheme.clear();
Avoid additional call to `get`.
src/java.desktop/windows/classes/sun/awt/windows/ThemeReader.java line 132:
> 130: dpiAwareWidgetToTheme.get(dpi).clear();
> 131: dpiAwareWidgetToTheme.clear();
> 132: valid = true;
The `valid` flag should be set to `true` even if the map was empty. Otherwise,
it may never be set to `true`. One more point to dropping `if (!isEmpty())`.
-------------
PR Review: https://git.openjdk.org/jdk/pull/13701#pullrequestreview-1451265920
PR Review Comment: https://git.openjdk.org/jdk/pull/13701#discussion_r1210472806
PR Review Comment: https://git.openjdk.org/jdk/pull/13701#discussion_r1210477915
PR Review Comment: https://git.openjdk.org/jdk/pull/13701#discussion_r1210476382
