- From: Tavmjong Bah <tav.w3c@gmail.com>
- Date: Fri, 29 Jan 2016 15:07:05 +0100
- To: "Tab Atkins Jr." <jackalmage@gmail.com>, www-svg <www-svg@w3.org>
- Cc: "public-fx@w3.org" <public-fx@w3.org>
On Mon, 2016-01-25 at 15:32 -0800, Tab Atkins Jr. wrote: > Per an FXTF meeting some time ago > <https://lists.w3.org/Archives/Public/www-style/2013Jun/0678.html>, > fantasai and I have been drafting fill/stroke as applied to text in > CSS, and with the extensions needed to handle multiline text, > hierarchical elements, and multi-layer (background-like) paints. I've added CSS Strokes as a topic for the joint CSS/SVG meeting. Here are some quick comments: stroke-align: This property, although highly desired and simple in principle, turns out to be quite difficult to define and implement. It has been moved out of the SVG 2 specification into a "strokes" module (along with 'stroke-dashcorner' and 'stroke-dashadjust'). For some of the problems, see: https://svgwg.org/specs/strokes/#SpecifyingStrokeAlignment http://tavmjong.free.fr/blog/?p=1257 It would also be nice to be able to give a numerical value to partially offset a stroke. You might consider adding the 'paint-order' property as this solves the common problem of distorted looking glyphs when stroke is above fill. stroke-linejoin: There are two additional values added in SVG 2: 'miter-clip' (with a much nicer fallback behavior than 'miter'). 'arcs' (much more appealing join for curved paths). stroke-miterlimit: With the 'miter-clip' and 'arcs' line joins, a '<number>' value makes more sense than an '<angle>' value. Computed value should be a number. stroke-dasharray: Yes, percentages are stupid when referenced to the diagonal of the containing block. Values in SVG can be lengths, percentages, or numbers. Numbers are in user-units. Relative to stroke-width may seem at first be an obvious choice but if stacking stroked path above each other (with different widths to build complicated paths) then having it in user-units makes sense. Interesting, the SVG spec does say "The ‘pathLength’ attribute on a ‘path’ element affects ‘stroke-dasharray’: each dash and gap length is interpreted relative to the author's path length as specified by ‘pathLength’." What this actually means, I don't know... but it would be quite handy to have percentages defined relative to path length (but probably not very useful for stroking text). stroke-dashoffset: Same comments as for 'stroke-dasharray'. Tav > Currently this lives in the Text Decoration 4 ED > <https://drafts.csswg.org/css-text-decor-4/>. Is this appropriate, > or > should it live somewhere else less directly text-centric? > > We're also unsure exactly how much of fill/stroke to define in this > spec. Should we take over the entire model, copying text from SVG, > or > should we only define the syntax, and the rendering parts that are > relevant to CSS, letting SVG define the rendering parts important to > it? > > ~TJ >
Received on Friday, 29 January 2016 14:07:43 UTC