AutoCAD

DWF, The Final Chapter, Part 4 (Learning Curve AutoCAD Tutorial)

1 Aug, 2007 By: Bill Fane

Finishing the story of AutoCAD and DWF files.


It was late on a hot, muggy afternoon. The clouds were so low and the humidity so high that it was almost foggy. Captain LearnCurve was on a special assignment, but as his driver raced wildly through the streets of Shanghai, he began to wonder if he would ever arrive safely. This guy could be a NASCAR driver.

Suddenly a thought . . .

Wait a minute! Shanghai?

Correct. British Columbia Institute of Technology (BCIT), where the Captain teaches, has an associated institute in Taicang, which is approximately one hour's drive from the Shanghai airport. The Captain was here to appraise its procedures and to give a series of guest lectures at the Chien Shiung Institute of Technology.

Wait another minute! I Googled that and didn't get one single hit!

I know. It's less than one year old and hasn't made its presence felt yet, but it is named after the prominent physicist Dr. Chien-Shiung Wu. (That entry will produce a great many Google hits.)

Anyway, back to the thought, which was that he had another column due. Digging through the voluminous notes of his prodigious memory, he realized that he had not said all there was to say about DWF files, a situation that he will now rectify.

My three previous articles ("DWF Secrets Revealed!," May 2007; "DWF: The Saga Continues, Part 2," June 2007; and "DWF, The Other Side, Part 3," July 2007) introduced and dissected AutoCAD's DWF file format, which is a plot-to-file format that can be used to distribute smaller, read-only versions of your drawings. The recipients can view, zoom, plot, and maybe (depending on how you created the DWF file) freeze and thaw layers, but they cannot edit the content of the drawings.

DWF files have two main uses: First, they can be posted to a Web page, which was their original intended use. Second, they can be marked up and returned to their originator. Last month's column focused mainly on the last feature. This time, I'm going to explore several separate topics.

It's a 3D World after All . . .
In the second article in this series, I made passing reference to the existence of 3D DWFs. Let's dig a little deeper into them.

Start a new drawing. Create several 3D objects in it and several 2D objects.

figure
Start by creating a drawing containing 2D and 3D objects.

Next, plot the drawing to an A-size sheet using the same DWF6EPLOT.PC3 plotter that we used in previous tutorials and then plot it again to an E-size drawing.

First, compare the file sizes. Unlike flat 2D drawings, the file size changes dramatically when the sheet size increases. In my case, a 152 KB DWG file produced a 75 KB A-size DWF and a whopping 421 KB E-size DWF.

Open the DWF files in Design Review. It does not support multiple documents, so you must run a separate copy of it for each file.

Zoom in close in each file. As per previous experience, the E-size DWF shows better detail and smoother edges than the A-size one.

figure

figure
An A-size DWF (top) is coarser and fuzzier than an E-size (bottom), but the E-size file is much larger.

Now that you have two 3D DWFs open in Design Review, let's look at some of the extra 3D functionality.

Wait a minute! They don't have any extra functionality! They're just flat 2D DWFs!

That's right. Remember our earlier analogy? We used the Plot command, so all it did was generate a flat, 2D DWF exactly as if we had plotted it to paper. On the other hand, we can still use the various markup tools.

Okay, let's go back to AutoCAD and try this again.

This time we will use the Publish command (File | Publish).

When the Publish dialog box opens, we can delete the paper space layout tabs if we want, because they aren't relevant to 3D work. Well, actually, they are, but the layout tabs just end up as flat 2D DWFs again. Make sure to activate the DWF File radio button in the Publish To region.

The next step is to click on the check mark at the right-hand side of the center column and then click on 3D DWF from the drop-down menu.

figure
The Publish dialog box set up to create a 3D DWF.

Click on Publish, supply a suitable file name, and then wait a bit. Publishing takes place in the background, so you can go on with other work, but it takes a while even for a relatively simple drawing.

Interestingly, 3D DWF files seem to be much smaller than 2D DWFs of 3D objects.

When it is finished, open the file in Design Review. It will look a little different from the previous examples.

figure
A Design Review display of a 3D DWF.

For starters, it now displays with a more realistic shaded appearance. An important point to note is that a 2D DWF file of 3D objects honors the visual style setting in the DWG, including edge overhang and jitter if the Conceptual style is current. On the other hand, a 3D DWF always generates the Realistic style regardless of the DWG setting.

Design Review realizes this file is a 3D DWF, so it makes the 3D tools available. Let's start with the basic viewing tools.

The Orbit button Orbit button lets us twist and turn the viewing direction. Simply click and drag anywhere on the screen. Clicking the black down arrow just to the right of the Orbit button lets you choose the Turntable function. It's almost exactly like the Orbit function with one slight difference. It's intended more for architectural applications, so it won't let you move the camera position below the horizontal plane or above 89


AutoCAD Tips!

Lynn Allen

Autodesk Technical Evangelist Lynn Allen guides you through a different AutoCAD feature in every edition of her popular "Circles and Lines" tutorial series. For even more AutoCAD how-to, check out Lynn's quick tips in the Cadalyst Video Gallery. Subscribe to Cadalyst's free Tips & Tools Weekly e-newsletter and we'll notify you every time a new video tip is published. All exclusively from Cadalyst!
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