Bug 16188 – SVG text redraw issues during scroll

• Component: SVG
• Status: RESOLVED FIXED

[Stefan Springer]

If SVG content is outside the visible space, and comes only into view when scrolling, the SVG might be drawn only partially. The problem is best reproducable when scrolling is slowly. Attachment will follow.

[Stefan Springer]

Created attachment 17590 [details]
(X)HTML file where the described problem occurs (the displayed formula is SVG).

[Stefan Springer]

Rendering of formula in the example file (see attachment in comment #1) is also incomplete (in another way, there is some incorrect clipping) when the displayed font size is made smaller via Control-"-" (making font size bigger via Control-"+" is OK).

[Eric Seidel (no email)]

I think this is a text-anchor="middle" redraw problem.  I think we already have a bug on this.

[Eric Seidel (no email)]

Hum... maybe I was remembering bug 15564 which is not really related.

Bug 15386 is possibly related as well.

[Eric Seidel (no email)]

Also possibly related to bug 15352 or bug 15402.

We'll need to build a smaller reduction which just shows the repainting bug.

[Adam Rofer]

I would like to add that this seems possibly related to another bug: <a href="http://bugs.webkit.org/show_bug.cgi?id=15799">Bug 15799</a>

I could be wrong, but this bug also relates to text repainting issues.

[Hiren Joshi]

Created attachment 29295 [details]
Testcase for showcasing text rendering issue 

When you resize the window, you get similar text cutoff behaviour as you get when scrolling. Incidentally, only happens on the rightmost SVG included in the parent XHTML document.

[Hiren Joshi]

Rendering issue also present on Webkit nightly 5528.16, r42162 on Leopard (10.5.6)

[Eric Seidel (no email)]

This is not fixed by bug 25268, but it's probably the same as bug 19366 and should be easy to fix in a follow-up patch.

[Eric Seidel (no email)]

This was fixed by the fix for bug 25431.  I'll make a test case for this case shortly.

[Eric Seidel (no email)]

Created attachment 29863 [details]
Add text repaint test

 5 files changed, 96 insertions(+), 0 deletions(-)

[Dave Hyatt]

Comment on attachment 29863 [details]
Add text repaint test

r=me

[Eric Seidel (no email)]

Committing to http://svn.webkit.org/repository/webkit/trunk ...
	M	LayoutTests/ChangeLog
	A	LayoutTests/platform/mac/svg/text/text-repaint-rects-expected.checksum
	A	LayoutTests/platform/mac/svg/text/text-repaint-rects-expected.png
	A	LayoutTests/platform/mac/svg/text/text-repaint-rects-expected.txt
	A	LayoutTests/svg/text/text-repaint-rects.xhtml
Committed r42964