[webkit-dev] Showing Baseline and Container Box

[Maciej Stachowiak]

On Jan 25, 2010, at 10:01 AM, Alex Milowski wrote:

> For all of my MathML rendering objects I've optionally compiled in a
> simple override to the paint() method to provide a visual representation
> of the containing box's boundary and the baseline position.  I've been
> using this to debug the layout of the Mathematics.
> 
> What is the proper way to wrap this kind of code when I go to create
> a patch?  Right now it is a compile time feature that I turn on with
> a define.

It's reasonable to use an ENABLE() flag for debugging features like this, in my opinion. I don't know if we have any direct precedent. (OTOH couldn't you get the boundary just using a style rule with a 1px border?)

> 
> Also, what I'd really like is the ability to inspect the full rendering
> tree associated with the MathML and turn on this outlining of the
> box and baseline for every rendering object in that subtree that reduces
> to a RenderBoxModelObject instance.
> 
> Is there some tool that could do this already or via some modification?

Not that I know of. I think when people want to debug the box model visually they usually just rely on style rules to set borders or backgrounds.

Regards,
Maciej