Bug 32086 – Repaint issues in text input under a scale transform

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Simon Fraser (smfr)]

Created attachment 44179 [details]
Testcase

The attached testcase shows a repaint bug when typing into a text input inside an element with a scale transform.

[Simon Fraser (smfr)]

This seems to be an issue where the subtree layout for the text input is using layout state, which is ignorant of the transform on a container.

[Simon Fraser (smfr)]

Created attachment 45809 [details]
Patch

Comment on attachment 45809 [details]
Patch

> +        (WebCore::RenderView::enableLayoutStateForSubtreeLayout):

This sounds like a method that enables layout state, but it isn’t. How about “canUseLayoutStateForSubtree()” (I don’t think Layout is necessary) or better yet “shouldDisableLayoutStateForSubtree()” (with the opposite return value of course)?

> +    bool enableLayoutState;

If you rename the method to shouldDisable… then you can rename the variable too.

> +    if (subtree) {
> +        RenderView* view = root->view();
> +        enableLayoutState = view->enableLayoutStateForSubtreeLayout(root);
> +        view->pushLayoutState(root);

Do you have to push if you disable?

> +    bool enableLayoutStateForSubtreeLayout(RenderObject* root) const;

Can drop “root”.

r- because I think the above name is too confusing.

[Simon Fraser (smfr)]

Created attachment 45827 [details]
Patch v2

[Simon Fraser (smfr)]

http://trac.webkit.org/changeset/52757