Bug 126658

Summary: Subpixel layout: RenderSlider's thumb position needs flooring.
Product: WebKit Reporter: zalan <zalan>
Component: Layout and RenderingAssignee: zalan <zalan>
Severity: Normal CC: jonlee, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on:    
Bug Blocks: 126283    
Description Flags
slider knob position none

Description zalan 2014-01-08 13:24:00 PST
LayoutUnit offset = percentageOffset * availableExtent;

with the following test case

<input type=range value=75 style="-webkit-transform: rotate(30deg)">

produces an off by one result when subpixel is on.

failed case:
Comment 1 Radar WebKit Bug Importer 2014-01-14 10:23:35 PST
Comment 2 zalan 2014-01-15 11:50:09 PST
Created attachment 221289 [details]
slider knob position
Comment 3 zalan 2014-01-15 11:51:19 PST
The new position does not make the slider's knob look less centered. It is just a different position. Prefer subpixel layout. (Can't compare to FF as this is a custom control)