NSView with layer cannot show content under window

Originator:gnachman
Number:rdar://29239686 Date Originated:11/13/2016
Status:Open Resolved:
Product:macOS + SDK Product Version:10.12
Classification: Reproducible:Always
 
Summary:
Normally, drawing a color with alpha less than 1 to a view with NSCompositingOperationCopy allows content beneath the window to show through. If the view has a layer, though, content beneath the window never sho

Steps to Reproduce:
1. Run the attached project


Expected Results:
Both windows' green circles should be translucent, blending the color beneath the window with green.

Actual Results:
Only the window on the right, which does not have a layer on its WTFCircleView, composites background content. The window on the left has an opaque green circle. See the screenshot, which demonstrates some of Photoshop's UI visible through my app's window.



Version:
10.12

Notes:
I tried -isOpaque on all the views and layers but that had no effect.

Configuration:
Always occurs.

Attachments:
'WTFLayers.zip' and 'Screen Shot 2016-11-13 at 4.22.45 PM.png' were successfully uploaded.

Comments


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