GC#drawIcon draws *.ico(for some icons) with black background on Windows 10

[tmssngr]

Describe the bug
Please run the attached snippet on Windows 10 (default Windows mode: Dark, default app mode: light). It will get the icons for certain file types and render them. For some reason, the background of the images is rendered in black.
ProgramImageTest.java.txt

To Reproduce
See above.

Expected behavior
The background should be transparent.

Screenshots

Environment:
Windows 10, Version 21H1 (OS Build 19043.1706)

[iloveeclipse]

@tmssngr :

• which Eclipse / SWT version is this?
• is this a regression? If yes, which version was OK?

[tmssngr]

This is reproducible with the latest SWT built from source (v4952r11). With bisecting I've found out that commit 22797d3 Revert "Revert "Bug 493455 - [win32] remove alpha and alphaData from Image"" introduced this bug.

[niraj-modi]

This is reproducible with the latest SWT built from source (v4952r11). With bisecting I've found out that commit 22797d3 Revert "Revert "Bug 493455 - [win32] remove alpha and alphaData from Image"" introduced this bug.

@jonathan.meier@outlook.com
Please have a look.

[niraj-modi]

I don't see this problem happening in Eclipse.

@SyntevoAlex @Phillipus
Do you see this problem in any of you Eclipse based applications ?
We are just trying to understand how severe is this problem.

[Phillipus]

I don't have those program icons on my system, so when I run the snippet the program icons I have render OK. @tmssngr Can we get an actual icon to test with? Also, is this Hi DPI?

[niraj-modi]

I don't have those program icons on my system, so when I run the snippet the program icons I have render OK. @tmssngr Can we get an actual icon to test with? Also, is this Hi DPI?

Please share a screen grab on how the icon looks for you.

[Phillipus]

Please share a screen grab on how the icon looks for you.

[Phillipus]

Found it.

I had to set Windows custom scaling to 200 or run the snippet with the argument -Dswt.autoScale=200

[niraj-modi]

Eclipse at HiDPI is working fine for External Program Icons:

So problem seems specific to this test-snippet only.

[Phillipus]

It seems to be only some Program icons that have this problem.

Try running this modified snippet:

Modified Snippet

import java.util.List;
import java.util.*;

import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.program.*;
import org.eclipse.swt.widgets.*;

public class ProgramImageTest {

    public static void main(String[] args) {
        final Display display = new Display();

        final List<Image> images = createImages(display);

        final Shell shell = new Shell(display);

        shell.addListener(SWT.Paint, event -> {
            int x = 0;
            int y = 0;
            for(Image image : images) {
                event.gc.drawImage(image, x, y);
                x += image.getImageData().width;
                x += 10;
                if(x > 400) {
                    x = 0;
                    y += 24;
                }
            }
        });

        shell.setSize(400, 300);
        shell.open();

        while(!shell.isDisposed()) {
            if(!display.readAndDispatch()) {
                display.sleep();
            }
        }

        for(Image image : images) {
            image.dispose();
        }

        display.dispose();
    }

    private static List<Image> createImages(Display display) {
        final List<Image> images = new ArrayList<>();

        for(Program p : Program.getPrograms()) {
            final ImageData data = p.getImageData();
            if(data == null) {
                continue;
            }

            images.add(new Image(display, data));
        }

        return images;
    }
}

[Phillipus]

Strange, now I am able to reproduce this with scaling at 100%:

[niraj-modi]

Interestingly problem is seen only with second run onward irrespective of zoom.
Even got it working with 200% as well:

Revised steps to reproduce the issue with test-snippet:

1. Switch the Windows Display zoom 100% to 200%(or visa versa)
2. Run the test-snippet, it will works on either zoom.
3. Close it and relaunch, problem is seen.