Bug 126663 - Subpixel layout: SliderThumbElement value needs flooring.
Summary: Subpixel layout: SliderThumbElement value needs flooring.
Status: RESOLVED INVALID
Alias: None
Product: WebKit
Classification: Unclassified
Component: Layout and Rendering (show other bugs)
Version: 528+ (Nightly build)
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: zalan
URL:
Keywords: InRadar
Depends on:
Blocks: 126283
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Reported: 2014-01-08 13:45 PST by zalan
Modified: 2014-01-14 15:59 PST (History)
3 users (show)

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Description zalan 2014-01-08 13:45:16 PST 
While calculating the thumb value at SliderThumbElement::setPositionFromPoint() as the result of a (touch) event, the subpixel on result is off by one.

position = offset.y() - (renderBox()->height() / 2) - trackBoundingBox.y() - renderBox()->marginBottom();

This is similar to bug 126658

failed case:
fast/forms/range/slider-transformed.html
fast/forms/range/slider-zoomed.html
Comment 1 Simon Fraser (smfr) 2014-01-08 15:29:43 PST 
Prefer new behavior.
Comment 2 Radar WebKit Bug Importer 2014-01-14 10:24:15 PST 
<rdar://problem/15815554>