Quoting David Christian Berg <david@...407...>:
With this thread we've hit some seriously tough discussion: Units. The SVG-spec as I understand it suggests pixels (relative units) as default unit but also allows absolute units within the SVG.
In some places. Some important things (like SVG paths!) can only be specified in px, nothing else.
Basically the other units inherited from CSS2 are not seemingly intended to be used in SVG, except for specifying overall document size and a few other things.
Personally I strongly favour absolute units, because given that you know the resolution of your output medium you get the same results for any output medium.
Unfortunately that's not possible because some things (e.g. paths) can only be specified in "relative" (px) units.
I believe that any SVG should either be using absolute units solely or relative units solely, but one should have the choice between those two.
Talk to the SVG WG about this.
Right now the only workable approach for total resolution-independence is the threefold approach I outlined earlier (to wit: specify document dimensions in absolute units, establish a viewBox, and use nothing but px in the actual document).
-mental