Re: [css3-background] color transition line

Bert and I have started going through the backlog of css3-background issues.
For the corner transition line, I'm recommending we make it undefined for now,
since the spec is known to be wrong, and we don't have an answer that we all
agree to be correct (and finding said answer will require significant further
investigation). Rather than leave the spec in its incorrect state, I'd like
to update it to say that it's undefined, and leave the defining up to CSS4 or
a later revision of CSS3.

Current text:
   http://www.w3.org/TR/2011/CR-css3-background-20110215/#corner-transitions
   # The center of color and style transitions between adjoining borders is
   # at the point on the curve that is at an angle that is proportional to
   # the ratio of the border widths. For example, if the top and right border
   # widths are equal, that point is at a 45° angle from the horizontal, and
   # if the top is twice the width of the right the point is at a 30° angle
   # from the horizontal. The line demarcating this transition is drawn
   # between the point at that angle on the outer arc and the point at that
   # angle on the inner arc.

Proposed text:
   http://dev.w3.org/csswg/css3-background/#corner-transitions (2nd para)

   | [ ... transitions must be contained ... ]
   |
   | If one of these borders is zero-width, then the other border takes up
   | the entire transitional area. Otherwise, the center of color and style
   | transitions between adjoining borders must be proportional to the ratio
   | of the border widths such that a function of its location is continuous
   | with respect to this ratio. However it is not defined what these
   | transitions look like or how “proportional” maps to a point on the curve.

~fantasai

Received on Wednesday, 18 January 2012 03:32:19 UTC