Simple line layout: Implement positionForPoint.

[zalan]

for single RenderText only at this point.

[Radar WebKit Bug Importer]

<rdar://problem/30593370>

[zalan]

Created attachment 302061 [details]
Patch

[zalan]

Comment on attachment 302061 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=302061&action=review

> Source/WebCore/rendering/SimpleLineLayoutResolver.cpp:217
> +    if (it.lineIndex() > lineIndex)
> +        return --it;
> +    // Now we have a candidate run.
> +    // Find the last run that still contains this point (taking overlapping runs with odd word spacing values into account).
> +    while (it != end() && (*it).logicalLeft() <= x && lineIndex == it.lineIndex())

The if condition could be eliminated by changing the while to this
while (it != end() && lineIndex == it.lineIndex() && (*it).logicalLeft() <= x)
but this way it's a bit more implicit. I don't really have a preference on this.

[zalan]

Created attachment 302062 [details]
Patch

[Antti Koivisto]

Comment on attachment 302062 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=302062&action=review

> Source/WebCore/rendering/RenderBlockFlow.cpp:3553
> +    if (!simpleLineLayout() || firstChild() != lastChild() || !is<RenderText>(firstChild()))

It might be good to have a comment explaining the tests (beyond just having !simpleLineLayout()).

> Source/WebCore/rendering/SimpleLineLayoutFunctions.cpp:220
> +unsigned positionForPoint(const LayoutPoint& point, const RenderText& renderer, const Layout& layout)

Might be better to call this something else since it doesn't return a Position object (unlike the RenderText version). Maybe textOffsetForPoint or similar?

> Source/WebCore/rendering/SimpleLineLayoutResolver.cpp:204
> +    auto it = Iterator(begin());

Can't this just be 

auto it = begin();

?

[zalan]

Created attachment 302076 [details]
Patch

[Antti Koivisto]

Comment on attachment 302076 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=302076&action=review

> Source/WebCore/rendering/SimpleLineLayoutResolver.cpp:201
> +        return Iterator(end());

return end()?

[zalan]

Created attachment 302078 [details]
Patch

[WebKit Commit Bot]

Comment on attachment 302078 [details]
Patch

Clearing flags on attachment: 302078

Committed r212615: <http://trac.webkit.org/changeset/212615>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.