Re: path and direction

> I appreciate that SVG paths can be defined just once in the <defs>
> element and then reused in rendering the paths, labeling the paths,

you can also re-use elements outside the <defs> section. The only difference is,
that elements in the <defs> section are not rendered initially, only their
instances (<use>-elements)

> and
> defining animation traversing the paths.  I've just started to
> seriously
> delve into SVG and I'm beginning to think that I'll need to duplicate
> the path definitions: one for each direction.  There are cases when
> <textPath> requires the path in one direction in order for the text to
> appear on the preferred side of the path, but <mpath> requires the
> path
> in the other direction for animating a shortest path solution.  Does
> 1.1 have some path direction control that I've overlooked?

Unfortunately not. I would also have a lot of use-cases for the inverse of a

Please make a SVG 1.2 feature request for that (separate email on this list) and
show them, that I am not the only one that has a use for it.

Also, please list use-cases, where you would need the ability to inverse the

I would see:

* animation along a path
* directed markers
* text on path

Direction of path matters in
* maps
* flowcharts
* orgcharts
* circuit diagrams

In interactive situations we should be able to change them using DOM methods or
XML attributes.

So, please do a official SVG1.2 feature request on that list and you are welcome
to add my above comments.

Meanwhile you have to inverse the path-data yourself using javascript. Kevin
Lindseys path-parser might help you:

If you ask him friendly, maybe he adds a method to inverse the path string.
Otherwise you could do it yourself and give the code back to Kevin.


How many worries simply flow away when you decide
to be somebody instead of just something ...
-- Coco Chanel

Andreas Neumann - Department of Cartography
Swiss Federal Institute of Technology (ETH)
ETH Hoenggerberg, CH-8093  Zurich, Switzerland
Phone: ++41-1-633 3031, Fax: ++41-1-633 1153

Received on Wednesday, 4 February 2004 23:12:05 UTC