Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!munnari.oz.au!brolga!bunyip.cc.uq.oz.au!lance!kirk!cameron
From: cameron@kirk.nmg.bu.oz (Cameron Stevenson)
Newsgroups: comp.sys.amiga
Subject: Re: Cad??
Message-ID: <2664@kirk.nmg.bu.oz>
Date: 10 Dec 90 02:39:40 GMT
References: <1990Dec6.170222.3600@cs.dal.ca>
Organization: Network Management Group, Bond University, Australia
Lines: 40

Just a few small points:

From article <1990Dec6.170222.3600@cs.dal.ca>, by dewolfe@ug.cs.dal.ca (Anarchy for Peace):
> In article <2657@kirk.nmg.bu.oz> cameron@kirk.nmg.bu.oz (Cameron Stevenson) writes:

>>screen display/resolution is needed. The acceptable minimum nowadays is about
>>1000x800x32 on a 15" screen. Obviously (as with most things in life) the more
>>the better....
> 
> Personally, I don't see the need for a 32 bit colour screen in Cad.  I always

You're correct; I can't see the need for 32 bit colour either. That was 32
colours ie. 1000x800 resolution x 32 colours as a minimum configuration. For
colour-shaded images obviously more colours are needed.

>>1. full 3D, with the ability to define 2D specific view information (most real
>>world objects are 3D, but require 2D drawing representations of the object to
>>be built. The CAD system should be able to maintain the linkage between this
>>3D/2D data.)
> 
> X-Cad 3D has this...
 
I'm not going to correct you on this one. I'll just say that I didn't see the
capability when I looked at X-Cad, and would be surprised if it was there. To
re-iterate: drawing views of an object (because of the nature of drawings)
should be different to 2D views of the 3D model. A good example (that I have
quoted before) is of a door. In 3D you usually want to see it closed, with
door handle, etc; in plan it will be shown open with a swing; in elevation it
will be shown closed again, in section the door is usually not shown at all.
The CAD system (as I said before) should be able to maintain the linkage
between these views, so that if you manipulate the object in one view it will
be changed in all other views.
Now I am willing to be educated (and impressed), but I don't think X-Cad can
do this... (over to you)

> Colin DeWolfe
> dewolfe@ug.cs.dal.ca
> dewolfe@iris1.ucis.dal.ca

Cameron Stephenson