[css4-text] Text decoration clearance proposal

Previously, I proposed the properties 'text-underline-skip',
'text-line-through-skip', and 'text-overline-skip' to allow text decoration
lines to break around glyph strokes that cross them [TD-skip]. The second
Last Call Working Draft of the CSS3 Text module incorporates some of the
proposed functionality by modification of the text decoration mode
properties [TD-mode].

The remaining functionality is proposed again here in new form. This
proposal addresses CSS level 4; there is no expectation that the proposal
will receive consideration for level 3.

Names: text-underline-clearance, text-line-through-clearance,
text-overline-clearance
Value: auto | <number> | <length>
Initial: auto
Applies to: all elements with and generated content with rendered text
decoration that skips glyphs
Inherited: yes
Percentages: N/A
Media: visual
Computed value: <length> | auto

These properties specifies the clearance around intersecting glyph strokes
for underline, line-through and overline text decoration. Possible values:

auto
  The user agent determines the clearance. If the clearance is the same on
every side of every stroke, the computed value is a <length>. Otherwise the
computed value is the keyword 'auto'.

<number>
  The clearance is the product of the given <number> and the computed
'font-size'. If inherited, the inherited value is the <number> and not the
computed <length>.

<length>
  The clearance is the given <length>.

Note: <number> and <length> values may be negative. This would produce at
least partial overlap with the glyph strokes. User agents may impose a
minimum and a maximum on actual values.

[TD-skip]
Etan Wexler.
"WD-css3-text-20021024 substantive comments".
Public correspondence.
30 January 2003.
<mid:WD-css3-text-20021024-comments@d20030130.etan.wexler>.

[TD-mode]
Michel Suignard, editor.
Section 9.5, "Text decoration mode: the 'text-underline-mode',
'text-line-through-mode' and 'text-overline-mode' properties", in "CSS3
module: text".
W3C Working Draft.
26 February 2003.
<http://www.w3.org/TR/2003/WD-css3-text-20030226#text-decoration-mode>.

Received on Sunday, 9 March 2003 06:40:29 UTC