[Webkit-unassigned] [Bug 185778] SVG text wiggles when changing its size through animation

bugzilla-daemon at webkit.org bugzilla-daemon at webkit.org
Tue Aug 20 00:43:04 PDT 2019


Sebastian Müller <seb.p.mueller at gmail.com> changed:

           What    |Removed                     |Added
                 CC|                            |seb.p.mueller at gmail.com

--- Comment #4 from Sebastian Müller <seb.p.mueller at gmail.com> ---
This is really ugly and bugs many of our enterprise customers of our commercial visualization library. We are forced to either tell them to render text in pixelated Canvas images or tell them to go and use a better (in this respect) browser.

I understand the problem, but I do think there should be a relatively simple solution to this problem that cannot be that performance critical. I haven't looked at the sources of other engines, but I closely inspected their rendering and I guess they are using the same optimized strategy: In order to get rid of the "wiggling"/jumping/dancing characters, it's not so important to quantize the font sizes to subpixels. As you can see in Chrome, they are also quantizing the font size of each single glyph. However they are calculating the exact accumulated position of each character in a long string. This approach should not affect the glyph cache hit rate because you can use the same cache entry at different zoom levels. All you need to do is use pixel exact glyph positioning. "sub pixel" isn't even necessary, as current the glyphs jumps around dozens of pixels on the screen so the error is at least 20 screen pixels in many situations and bringing that error down to 1px would be a *huge* improvement.

You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-unassigned/attachments/20190820/58cad75a/attachment-0001.html>

More information about the webkit-unassigned mailing list