On Tue, 18 Oct 2011 14:20:40 -0400, John Delacour <j...@bd8.com> wrote:
> At 14:01 -0400 17/10/11, Erik Dahlstrom wrote: > > >> On Mon, 17 Oct 2011 03:52:58 -0400, John Delacour <j...@bd8.com> wrote: >> >>> ... >>> <http://www.w3.org/TR/SVG/images/animate/anim01.svg> >>> ... >> >> The "jerkiness" you see is due to selecting different font-sizes, it's >> not >> a SMIL issue. You'd get a smoother animation if the same glyph outlines >> were used all the time. > > Thanks Erik, but that doesn't explain why it has no jerkiness in > Safari, and the code doesn't actually referto font-size in the > animation. Maybe I wasn't clear enough: any transform may affect the size of the text on screen. Now, the browser knows this, but there are (at least) two ways you can select the glyph outlines - before or after the transforms have been applied, so in one case you extract glyph outlines at size 14px and then scale those, and in the other case if you had a scale(2) transform you might extract the outlines at actual fontsize 28px. Subpixel fontsizes combined with this can lead to a sort of staircase effect, as seen in some browsers. This was mentioned in the talk by Google Docs at SVG Open the other day, http://svgopen.org/2011/registration.php?section=abstracts_and_proceedings#paper_52. The solution that was proposed was to use text-rendering="geometricPrecision" to mean that you want the smoothly scaled transition. However, this doesn't yet solve the problem since that fix has not yet been made in all the different browsers. Note that geometricPrecision can lead to text that is harder to read, and the spec says that by default more importance should be given to text legibility, see http://www.w3.org/TR/SVG11/painting.html#TextRenderingProperty. A workaround could be to convert the outlines to paths e.g in Inkscape, and then animate those. -- Erik Dahlstrom, Core Technology Developer, Opera Software Co-Chair, W3C SVG Working Group Personal blog: http://my.opera.com/macdev_ed ------------------------------------ ----- To unsubscribe send a message to: svg-developers-unsubscr...@yahoogroups.com -or- visit http://groups.yahoo.com/group/svg-developers and click "edit my membership" ----Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/svg-developers/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/svg-developers/join (Yahoo! ID required) <*> To change settings via email: svg-developers-dig...@yahoogroups.com svg-developers-fullfeatu...@yahoogroups.com <*> To unsubscribe from this group, send an email to: svg-developers-unsubscr...@yahoogroups.com <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
