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AutoCAD

Circles and Lines: Set the Stage for 3D

6 Jul, 2006 By: Lynn Allen

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Use the new 3D drawing template and set up your drawing space to get the most from AutoCAD 3D.

I'll be the first to admit that the 3D functionality in AutoCAD over the years has been painful at best. I taught AutoCAD for 12 years and my least favorite course to teach was AutoCAD 3D. I dreaded the UCSICON discussion, forever holding up my fingers pointed in three different directions and trying to convince the dazed students that their 3D dreams were in fact a possibility. With the new 3D features in AutoCAD 2007, I suspect that teaching a 3D course today would be a pleasure!

It would take an entire book to properly cover all the new 3D functionality in AutoCAD 2007, so I'll provide enough instruction over the next few months to get you on the right track. We'll dive into the many different elements of 3D, such as creating 3D objects, editing 3D objects, visualization techniques and the like. Of course, we'll talk about the all important methods of getting those 3D objects back into 2D drawings (because that's what we get paid to do -- right?). To begin, let's properly set the stage for 3D.

Start a 3D Drawing
AutoCAD 2007 has added a new 3D template file called ACAD3D.DWT. If you plan on working in 3D, this template is a great way to start.

The UCSICON displays X, Y and Z coordinates and is color coded to help you remember which direction is which: X is always red, Y is green and Z is blue. If you intend on diving into 3D, it behooves you to memorize the axes and their corresponding colors for quick recall. Rumor has it the colors were assigned to the axes to correlate with the true color designation of RGB (red, green, blue). Hence, RGB equals XYZ (perhaps this will help you remember which is which).

The grid from days past has returned and is available to help you keep a proper perspective as you work in 3D. You can even set the grid so it repopulates as you zoom in. The cursor is clearly 3D and the same RGB color coordination applies to the cursor. The shorter axes on the cursor indicate a negative direction.

Even though it's much easier to detect which X, Y and Z direction you are drawing in AutoCAD 2007 -- something that has been quite a chore in previous releases -- you'll find yourself relying on this information less and less. So much of the new 3D design space is visual, that I rarely move my UCS around anymore. Only those of you who do intricate 3D work may need to resort back to some of the practices of the days of yore.

There is a new tab in the Options command specifically focused on 3D modeling. Set the left half of this tab to your liking. Figure 2 shows the way I prefer to work.

If you like the X, Y and Z cursor to be labeled at all times, simply check the Label axes in standard crosshairs box to add this information.

The best new 3D feature is the ability to select an existing surface to draw on. Dynamic UCS, as it's called, will definitely be your preferred mode of designing in 3D. Though I'll discuss this in more detail in another column, you can indicate you'd like the X, Y and Z direction to appear the minute you select a surface to draw on (figure 4). This ability makes it easy to make sure you're drawing everything in the proper direction and can be turned on by checking the Show labels for dynamic UCS option.

I like to display all the UCS Icon information. Incidentally, AutoCAD 2007 lets you draw in perspective mode now -- something that was definitely forbidden in the past.

If you use dynamic input, you might want to select Show Z field for pointer input so that an additional box displays with the Z coordinate.

All Things 3D
As mentioned, new life has been breathed into the Grid command. Right-click on Grid on the Status bar to enter the Drafting Settings command. The lower right corner of the Snap and Grid tab controls the grid behavior in 3D (figure 6). Turning on Adaptive grid limits the density of the grid when you zoom out. Selecting Adaptive grid gives you the added option to allow a subdivision below grid spacing, which automatically repopulates the grid as you zoom in. And you might find the new Follow Dynamic UCS option helpful to clearly distinguish the plane you are drawing on. As you move from one UCS to another, the grid moves with you.

The new Workspace's goal is to help you set up the proper 3D environment. The 3D Modeling workspace turns on the Tool Palette (complete with the new Materials tabs), the fabulous Dashboard (which I'll dive into deeper another time), moves the Command line to the lower left corner and a few other minor adjustments. How anyone can work in this overcrowded environment is beyond me -- I immediately anchored the dashboard to the right and the tool palette to the left, then proceeded to put everything back the way I like it. It's easy to anchor any palette, and I strongly recommended doing so by undocking the palette, right-click on the palette bar and select Anchor left or Anchor right. This anchoring makes the palettes readily available, but not in the way.

The new Dashboard is a one-stop shop for all things 3D. Although there are a few tools that didn't make it to the Dashboard, you'll find just about everything you need here for creating and editing 3D objects, materials, lights, cameras and more. You no longer have to rummage through the pull-down menus in search of the 3D tools. I love the new Dashboard and consider it an essential part of my 3D workspace.

Last but not least -- be sure to keep the DUCS (Dynamic UCS) option on the Status bar on when drawing in 3D. It improves your 3D experience many times over.

Kick Start 3D
These tips should kick start you into the much friendlier world of 3D in AutoCAD 2007. Give it a go and you might just find yourself becoming a 3D addict like myself! Until next month -- Happy AutoCAD-ing!