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Re: [whatwg] <canvas> feedback

From: Rik Cabanier <cabanier@gmail.com>
Date: Tue, 8 Apr 2014 16:50:48 -0700
Message-ID: <CAGN7qDDpGt41MCT35ieQvBij1xUcLgXCe1NPv-uV6DSCDvCjBQ@mail.gmail.com>
To: Ian Hickson <ian@hixie.ch>
Cc: WHAT Working Group <whatwg@whatwg.org>
On Mon, Apr 7, 2014 at 3:35 PM, Ian Hickson <ian@hixie.ch> wrote:

> ...
>
> > > > Stroking will be completely wrong too, because joins and end caps
> > > > are drawn separately, so they would be stroked as separate paths.
> > > > This will not give you the effect of a double-stroked path.
> > >
> > > I don't understand why you think joins and end caps are drawn
> > > separately. That is not what the spec requires.
> >
> > Sure it does, for instance from
> >
> http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#trace-a-path
> > :
> >
> > The round value means that a filled arc connecting the two
> > aforementioned corners of the join, abutting (and not overlapping) the
> > aforementioned triangle, with the diameter equal to the line width and
> > the origin at the point of the join, must be added at joins.
> >
> > If you mean, "drawn with a separate fill call", yes that is true.
> > What I meant was that they are drawn as a separate closed path that will
> > interact with other paths as soon as there are different winding rules or
> > "holes".
>
> The word "filled" is a bit misleading here (I've removed it), but I don't
> see why that led you to the conclusion you reached. The step in question
> begins with "Create a new path that describes the edge of the areas that
> would be covered if a straight line of length equal to the styles
> lineWidth was swept along each path in path while being kept at an angle
> such that the line is orthogonal to the path being swept, replacing each
> point with the end cap necessary to satisfy the styles lineCap attribute
> as described previously and elaborated below, and replacing each join with
> the join necessary to satisfy the styles lineJoin type, as defined below",
> which seems pretty unambiguous.
>

Thinking about this some more, it looks like you came around and specified
stroking like I requested from the beginning.
For instance,
http://lists.w3.org/Archives/Public/public-whatwg-archive/2013Oct/0354.html
 or
http://lists.w3.org/Archives/Public/public-whatwg-archive/2013Oct/0213.html
Now that you made that change, 'addPathByStrokingPath' is specified
correctly. I still don't know how it could be implemented though... (It
*could* as a shape but not as a path)
Received on Tuesday, 8 April 2014 23:51:16 UTC

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