RE: absolute coordinates on svg paths

Jose,

During the period when SVG 1.0 was defined, the SVG Working Group decided that there was high implementation complexity absolute units on paths, and thus decided to postpone that feature to a future version of the language. Furthermore, implementation experience along with corresponding content developer experience, showed that absolute units on geometry complicated implementations and did not do a good job of addressing content developer needs.

 

SVG 1.1 was just a modularization exercise to allow for mobile profiles of the SVG language, so no new features were added then. With SVG 1.2, the SVG WG decided that the best technology approach was to add a few powerful low-level building blocks to the language to enable great flexibility for custom graphics objects and user interface controls rather than add dozens of piecemeal extensions to the language. The key features in SVG 1.2 for custom graphics objects were sXBL (http://www.w3.org/TR/sXBL) and the additional of various APIs that could be invoked within the definition of custom graphics objects. The key point is that absolute units have not proven to be a useful feature. In fact, with SVG Tiny, absolute units have been removed entirely except for defining the intrinsic size of the SVG drawing.

 

Jon Ferraiolo

Member SVG WG

Adobe Systems, Inc.

 

 

________________________________

From: www-svg-request@w3.org [mailto:www-svg-request@w3.org] On Behalf Of Jose Ignacio Villar
Sent: Sunday, January 01, 2006 10:50 AM
To: www-svg@w3.org
Subject: absolute coordinates on svg paths

 

Hi All,

Are SVG paths so different to other SVG shapes that you should never preffer specifying units as absolute?

I'm using it to develope a format translator from Gerber to SVG. Gerber is a vectorial format for printed circuit boards used in electronics. 
In the file there are rects, circles, etc,...  that represents real life shapes with absolute dimensions in inches and mm.
I've succed to implement circles, ellipses, ovals rects etc, with SVG built in absolute meassures, but i've found I can't do the same with paths :(. 
The shapes already implemented with absolute units, appears on the screen with it's real dimension and this is very helpful when previewing your design. Is there any alternative to see on the screen paths with its real dimensions? 

Thanks for your reply, David ;)
José Ignacio Villar.

 

On 1/1/06, David Woolley < david@djwhome.demon.co.uk <mailto:david@djwhome.demon.co.uk> > wrote:


> Theres a thing I've never understood, and it is why you can't specify 
> absolute units like cm or in to SVG paths?. Is there any implementation

Because the graphics would no longer be scalable?