Bug 95498 – [New Multicolumn] Implement unforced breaking in columns

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

[Dave Hyatt]

Implement proper unforced breaking inside columns. Lines and objects now break across boundaries correctly. Unforced breaks work. Forced ones are muddled and still use region rather than column. I'll cover that in a separate bug.

[Dave Hyatt]

Created attachment 161556 [details]
Patch

Comment on attachment 161556 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=161556&action=review

> Source/WebCore/ChangeLog:36
> +        thus forcing us to repaginate everythign.

typo: everythign

> Source/WebCore/ChangeLog:42
> +        Always return the last region if it's a set, regardless of the extendLastRegion boolan.

typo: boolan

> Source/WebCore/rendering/RenderBlock.cpp:1455
> +    } else if (isRenderFlowThread()) {
> +        pageLogicalHeight = 1; // This is just a hack to always make sure we have a page logical height.
> +        pageLogicalHeightChanged = toRenderFlowThread(this)->pageLogicalHeightChanged();

I’d like to see RenderBlock doing less testing for known subclasses of itself and more calling virtual functions that have overrides in those subclasses. This is a general comment, though, and you don’t need to address it in this iteration.

> Source/WebCore/rendering/RenderRegion.h:111
> +    // The top of the nearest page inside the region. For RenderRegions, this is just the logical top of the
> +    // flow thread portion we contain. For sets, we have to figure out the top of the nearest column or
> +    // page.

“nearest” could imply that we search in both directions, but we never return the top of a page that’s *after* the offset, do we?

[Dave Hyatt]

Landed in r127267.