On Tue, 2 May 2023 15:05:23 GMT, Alexey Ivanov <[email protected]> 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%.
>
> src/java.desktop/share/classes/sun/swing/CachedPainter.java line 318:
>
>> 316: public Image getResolutionVariant(double destWidth, double
>> destHeight) {
>> 317: int w = (int) Math.floor(destWidth + 0.5);
>> 318: int h = (int) Math.floor(destHeight + 0.5);
>
> Isn't it what `Region.clipRound` does?
No, Region.clipRound does something little different than what I intend to do in
this code .
It works same as my code for 0.25 and 0.75 case. But not for 0.5 case.
For example in case of destwidth and destHeight = 19.5,
for my current code I see them rounded to 20, while with clipRound it is
rounded to 19.
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PR Review Comment: https://git.openjdk.org/jdk/pull/13701#discussion_r1185438958