Bug 569168

Summary:	[Mac][BigSur]Gradient separator line appears on action tool bars on macos bigsur
Product:	[Eclipse Project] Platform	Reporter:	Sravan Kumar Lakkimsetti <sravankumarl>
Component:	SWT	Assignee:	Platform-SWT-Inbox <platform-swt-inbox>
Status:	NEW ---	QA Contact:
Severity:	normal
Priority:	P3	CC:	a.nesheret, lshanmug, p.beauvoir, peter
Version:	4.18
Target Milestone:	---
Hardware:	PC
OS:	Mac OS X
See Also:	https://bugs.eclipse.org/bugs/show_bug.cgi?id=569277
Whiteboard:
Bug Depends on:
Bug Blocks:	575659, 569361

Description Sravan Kumar Lakkimsetti

2020-11-25 07:03:13 EST

On macos users can see a horizontal gradient separator in the action tool bar. 

See https://bugs.eclipse.org/bugs/show_bug.cgi?id=564885#c27 for screen shot

This appears in light theme as well as dark theme. Also the gradient separator moves when the view is resized.

Comment 1 Sravan Kumar Lakkimsetti

2020-11-25 07:12:08 EST

While fixing bug 564885 I found that there are two problems with the background.

1. Background image is created with a 2 pixels wide white line. This was fixed in bug 564885
2. Location for background image is not stable for tool bar. 

I found phase calculation at this location  https://git.eclipse.org/c/platform/eclipse.platform.swt.git/tree/bundles/org.eclipse.swt/Eclipse%20SWT/cocoa/org/eclipse/swt/widgets/Control.java#n1304 is the root cause. Still we are figuring out what is the impact of this.

Since this is in Control used by many widget it is not good idea to modify Control class during RC1 phase.