Bug 7235 – Pure CSS Tooltips method renders wrong and creates artifacts

• Status: RESOLVED
• Resolution: FIXED
• Component: CSS

[Jeremy Knope]

Using the 'Pure CSS Tooltips' method described in the url given in report (http://www.cybersaps.org/2004/01/Pure-css-tooltips.html) ends up with funky draw problems in Safari (and WebKit nightly.)  This will render fine in Firefox.  Hope to see this fixed, being an excellent no-javascript-fancy-tooltip method.

I pulled a more noticeable example from an app at my work that renders really bad:
http://www.macsaresexy.com/files/pure_css_tooltips.html

[Jeremy Knope]

Created attachment 6461 [details]
uploaded version of css render bug example

wanted to upload a version of the linked file so don't have to rely on my link

[Alexey Proskuryakov]

This looks quite similar to bug 7204.

[Jeremy Knope]

(In reply to comment #2)
> This looks quite similar to bug 7204.
> 

sounds like it could be, 7204 references javascript and DOM usage of producing content where this one is pure CSS, html is already there but the use of CSS in doing some tricks like :hover, display: none etc. with elements inside an <a> tag seem to get rendered funny.

but could be similar in how it's rendered/handled internally.   just wanted to clarify that this one isn't javascript & DOM related I don't think.

Created attachment 6469 [details]
Reduced testcase

This is a repaint issue

This is the case of a positioned layer that has an enclosing relpositioned inline which is handled in updateLayerPosition, but not in getAbsoluteRepaintRect* and absolutePosition, hence the incorrect repaint.

Created attachment 6491 [details]
First cut at a fix

This fixes the bug by implementing the logic from RenderLayer::updateLayerPosition in RenderBox::absolutePosition and RenderBox::computeAbsoluteRepaintRect.
It's probably a bad idea to repeat that code twice, so I'll welcome suggestions on that (including naming).

[Dave Hyatt]

Comment on attachment 6491 [details]
First cut at a fix

Unfortunate code duplication, but eventually I wanted to rework absolutePosition to use layers anyway.

Created attachment 6506 [details]
Patch including manual test and changelog entry

Left in the duplicate code for now.

[Dave Hyatt]

Comment on attachment 6506 [details]
Patch including manual test and changelog entry

r=me

*** Bug 3875 has been marked as a duplicate of this bug. ***