Bug 68304 – offsetTop/offsetLeft return the wrong values for horizontal-bt/vertical-rl writing modes

• Status: RESOLVED
• Resolution: FIXED
• Component: Layout and Rendering

[Ojan Vafai]

http://tinyurl.com/3h8ejbj

<div style="position:relative">
<div style="-webkit-writing-mode:vertical-rl;background-color:green;width:400px;height:100px;">
    <div id=foo style="background-color:yellow">foo</div>
</div>
</div>

<div style="position:relative">
<div style="-webkit-writing-mode:horizontal-bt;background-color:red;width:400px;height:100px;">
    <div id=bar style="background-color:orange">bar</div>
</div>
</div>

I believe foo should have offsetLeft of something like 380, instead of 0 and bar should have offsetTop of something like 80 instead of 0.

[Ojan Vafai]

Created attachment 108888 [details]
Patch

[Dave Hyatt]

Comment on attachment 108888 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=108888&action=review

r=me, but you can rename xFlippedForWritingMode and yFlippedForWritingMode to left() and top(). If you want to go further we could rename locationIncludingFlipping() to topLeftLocation() and locationOffsetIncludingFlipping() to topLeftLocationOffset(). I'd add copious warnings in the header too that these represent your location relative to your container as a physical offset, and that this is rarely what you want in layout() methods.

> Source/WebCore/rendering/RenderBox.h:53
> +    LayoutUnit yFlippedForWritingMode() const { return locationIncludingFlipping().y(); }
> +    LayoutUnit xFlippedForWritingMode() const { return locationIncludingFlipping().x(); }

Rename these to left() and top().

[Ojan Vafai]

Committed r96152: <http://trac.webkit.org/changeset/96152>