[OpenJDK 2D-Dev] [10] Review Request JDK - 8164811 : [hidpi]Tests fail with OpenGL Rendering

[Prahalad Kumar Narayanan]

Hello Pankaj

The changes look fine to me. 
The back buffer -BufferedImage here is scaled and Graphics2D corresponding to the back buffer is appropriately transformed.

Just a minor correction. Doesn't require another webrev:
. Kindly edit multi-line comments at Line: 254 to reflect the coding guideline
/*
 * Start of multi-line comments
 */

Thanks
Have a good day

Prahalad
 
-----Original Message-----
From: Sergey Bylokhov 
Sent: Wednesday, November 08, 2017 2:04 AM
To: Pankaj Bansal; Philip Race; Prem Balakrishnan
Cc: 2d-dev at openjdk.java.net; swing-dev at openjdk.java.net
Subject: Re: [OpenJDK 2D-Dev] [10] Review Request JDK - 8164811 : [hidpi]Tests fail with OpenGL Rendering

Looks fine, thank you!

On 07/11/2017 05:09, Pankaj Bansal wrote:
> Hi Sergey,
> 
> << One more thing which can improve the fix is to add "uiScale > 1.0" as an additional @run step to the tests, so these tests will fail before the fix even on common lowdpi(100%) systems.
> I have updated the webrev for the changes.
> 
> I will like to point out that, there are 9 test cases mentioned in the bug. But only 5 fail without fix.  4 tests pass because of following reasons.
> 
> 1. SetShapeAndClickSwing.java,  TranslucentJComboBox.java,  
> TranslucentWindowClickSwing.java These tests don’t use the TranslucentWindowPainter as in these tests, the PerPixelTransparency which means the alpha of the window is set 1.0. Instead these tests change the window Opacity which is handled differently. So in these tests are scaled properly and don’t fail without the fix.
> 
> 2.  PerPixelTranslucentSwing.java
> This test passes as there is a problem in the way test is written. It is trying to check the transparency of window by comparing the robot picked color with Foreground color. But with HIDPI, the color value is picked from wrong location, but still the test passes as the picked value is not equal to the Foreground color. So we should check the color value with Background color. I was not very sure if I should fix this in this webrev, so I have created a separate issue for this. https://bugs.openjdk.java.net/browse/JDK-8190861. I will fix this test differently.
> 
> So I have added the additional @run with uiScale in 5 tests that fail 
> without fix and PerPixelTranslucentSwing.java as this is a test 
> problem and this test fails when corrected
> 
> Webrev:
> http://cr.openjdk.java.net/~pbansal/8164811/webrev.03/
> 
> 
> Regards,
> Pankaj Bansal
> 
> 
> -----Original Message-----
> From: Sergey Bylokhov
> Sent: Tuesday, November 7, 2017 1:45 PM
> To: Pankaj Bansal; Philip Race; Prem Balakrishnan
> Cc: swing-dev at openjdk.java.net; 2d-dev at openjdk.java.net
> Subject: Re: [OpenJDK 2D-Dev] [10] Review Request JDK - 8164811 : 
> [hidpi]Tests fail with OpenGL Rendering
> 
> Thanks for clarification. Looks fine.
> One more thing which can improve the fix is to add "uiScale > 1.0" as an additional @run step to the tests, so these tests will fail before the fix even on common lowdpi(100%) systems.
> 
> On 06/11/2017 23:20, Pankaj Bansal wrote:
>> I am assuming you are talking about changes in UpdateWindow function in TranslucentPainter.
>> I think it is doing exactly what was happening before the fix. It called getBackBuffers and saved it in bb initially and then,  If the update fails, "done" will be false and it was calling getBackBuffers (true) to save the buffer in bb everytime. So it was calling getBackBuffers() everytime the update fails. Also the createBackBuffers function is creating backbuffer only once and then just returning it if the width and height remains same. So when I call update(getBackBuffers(false)), it will just return the backBuffers, not create it. So this change has added a call to getBackBuffers, but without it, I will have to add a check to see if the Image is BufferedImage or VolatileImage to decide to transform the Graphics or not.


--
Best regards, Sergey.