Bug 197957 - Translucent border rendering issue in combination with gradient background
Summary: Translucent border rendering issue in combination with gradient background
Status: RESOLVED INVALID
Alias: None
Product: WebKit
Classification: Unclassified
Component: Compositing (show other bugs)
Version: Safari Technology Preview
Hardware: Mac macOS 10.14
: P2 Normal
Assignee: Nobody
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2019-05-16 12:32 PDT by Jonas Treub
Modified: 2019-05-17 12:42 PDT (History)
4 users (show)

See Also:

Attachments
Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Jonas Treub 2019-05-16 12:32:26 PDT 
Overview:

Translucent border looks off when rendering in combination with a gradient background.

1) View the example: https://codepen.io/jonastreub/pen/JqNNPP

2) Notice that the border looks off on the top and bottom sides

Expected Results: translucent border to darken the background evenly
Comment 1 Radar WebKit Bug Importer 2019-05-17 11:57:24 PDT 
<rdar://problem/50900823>
Comment 2 Simon Fraser (smfr) 2019-05-17 12:42:44 PDT 
This is correct behavior. The background is tiled to the inside of the border, so you're seeing background tiling behind the alpha border.

Safari, Chrome and Firefox all render this the same way.