Re: scales and standards - DON'T DO IT that way!

cal@antares.aero.org
Fri, 16 Sep 1994 18:27:13 -0700


Units in Inventor -

Um, why does moving the object out change the scale? It sounds like Inventor
is broken if it matters whether an object whose numbers are expressed in
meters is in or out of an object whose numbers are expressed in feet. Of
course, that probly means I am misinterpreting what you mean about that;
please enlighten me.

In fact, in our conceptual design environment (called VEHICLES; many published
papers are available; send me e-mail if you are interested), every number in
every model had the unit name closely connected with it. I do not expect that
to be necessary in the case of VRML, since we here are mostly talking about
physical dimensions of objects, so the units can be object-wide, so to speak.

But an object defined to use meters should be imbeddable into an object
defined to use feet with no change at all in the "inside" object: if I have a
6 inch cube, it cannot sensibly matter to its own size in any length units at
all whether it is in a 10 foot room or a 1000 foot arena, except when I
compute how to display it.

more later,
cal