Dialog Box August 2005

16 Aug, 2005 By: Cadalyst Staff Cadalyst

Readers have their say.

To be considered for publication, you must sign your letters and include your company's name, address, and daytime telephone number. Letters are subject to editing for length and clarity. Send letters to:
Cadalyst Dialog Box
859 Willamette Street
Eugene, OR 97401
fax: 541.984.5328
Better Bylayer
Last month, B.G. Ottley asked:
Is there an AutoLISP routine that can transfer objects in the block from layer 0 to the layer the block resides on and change color and linetype to bylayer, so that we can control linetype and color in our drawing?

The real issue is that objects were created with colors other than Bylayer, not that they are on layer 0. Because he is Xreffing the drawing, if all objects were color Bylaer, he could change all colors by changing the xref layers (such as x-plan|a-wall). If there are objects drawn on layer 0, he can change their color by changing the color of the layer he inserts the xref on. It is good practice to make a special layer for xref attachment such as $XREF (the dollar sign just sorts the layer to the top of the list).

To quickly fix drawings with objects not Bylayer, use the layer translator (LAYTRANS). Load the exact same drawing as a template, and Map Same. Be sure to check changing color and linetype to Bylayer in the options box.

Also note that "bad" CAD habits are not the exlusive domain of architects. As an architect, I have the same problem with drawings from my consultants, other architects and manufacturers as well.

— Dan Allen

DWG Dogfight
In the July issue, we discussed Autodesk's escalating battle against DWG files that aren't created in an Autodesk product and asked for feedback about your experiences with DWG files that originated in non-Autodesk applications.

Undermining themselves
Many of our colleagues do not use Autodesk products in their design process. It is extremely rare that we have any difficulty opening the DWG files they send us. Whenever we get a DWG file that AutoCAD will not open, I use a free version of an Intellicad-based product and generally have no problem opening the file. It probably won't be long before our firm changes CAD products and no longer uses AutoCAD. It's simply not a good value, considering that for the price of the newest version of AutoCAD I can upgrade my workstation and buy one of the Intellicad-based products with HVAC, piping, or electrical design add-on software. Autodesk is probably undermining itself more than the Open Design Alliance, but I think they've been undermining themselves for years. I'm just glad that the competitors are finally catching, and even surpassing, some of the Autodesk products.

— Brian Singleton

Illustrator issue
Illustrator and other programs create invalid splines in DXF files that makes AutoCAD lock up. It happens if osnaps are activated and you hover above any invalid spline.

This is a known bug and should in my opinion be worked around by AutoCAD so it doesn't lock up, but the reason I've heard is that the spline is not correctly created by the other softwares.

— Jimmy Bergmark

DXF difficulties
The only problems we have with non-Autodesk software is from very old software that's trying to save to r13 DWG. But with DXF files, we have more problem with the Autodesk versions than the others. On both, we're taking the word of our customers on how they created their files.

— Roger Renfrow

Bad DWG, shame, shame
We've been hearing for years from MicroStation users about how bad the DWG is when translated into DGN. Of course you had to buy a $30,000 dual-screen workstation to see any of the "problems" of translated files. They basically didn't like AutoCAD layer names attached to their sacrosanct 1-63 level names.

I don't have the examples you are seeking, but I do have a strong sense of foreboding when opening AutoCAD drawings with Version 8 of MicroStation.

We've heard for years how "powerful" MicroStation is compared to AutoCAD, all the while trying to use cryptic commands in MicroStation to do things that are second nature in AutoCAD. We're awash in UCMs that seldom do anything constructive while burdened down with the useless MicroStation database display information.

Just give me the same info as the AutoCAD List command, for crying out loud!

Don't even get me started about their user interface. When God invented customization, MicroStation must have thought He said "miniaturization," and so we have minimal utilization.

Bentley has jumped on the Open DWG Alliance fence instead of changing its product to be more user-friendly.

— Robert Zipprich, Electrical Designer

About the Author: Cadalyst Staff

Cadalyst Staff