A Perfect View15 Jun, 2011 By: Lynn Allen
Circles and Lines: After years of requests, AutoCAD users' wishes come true with the Transparency property for objects and layers.
Editor's Note: This article was originally published in the Winter/Spring 2011 issue of Cadalyst magazine.
One of the biggest crowd-pleasers that was introduced in AutoCAD 2011 (and remains available in AutoCAD 2012) is transparency. Perhaps that's because it has been on the top of many a wish list for numerous years. The biggest request was for transparent hatches (because solid fills mask all the objects underneath them), but AutoCAD 2011 took it one step further. Transparency is now an actual object property that can be applied to objects and layers.
Here's a perfect example of where transparency could really help. The rooms are color-coded with solid fills, but no one can see the furniture or the doors that lie beneath them.
Solid fills cover valuable information in this drawing.
Selecting one of these solid fills displays the Hatch Editor ribbon, where you will find a slider bar for the Transparency object property.
Sliding that bar to a value of 80 adds a significant amount of transparency. The higher the value, the more transparent the object becomes. The maximum transparency value allowed is 90 (any higher and the object is nearly invisible, pretty much defeating the purpose).
Because Transparency is an object property, it shows up in the Properties palette along with Layer, Color, and Linetype. You can modify Transparency by layer, by block, or to a specific value. It's handy that you can now apply transparency to layers when you want to control the visibility of all objects on a specific layer. In the Layer Manager, you can apply transparency to an entire layer or to a layer in a viewport.
You can set a transparency value by layer or per viewport in the Layer Manager.
One nice feature with hatching is that you can now set up layer, color, and transparency settings to create new hatches regardless of the current drawing properties. All of these settings are on the ribbon when you enter the Hatch command.
As a side note: Don't confuse this new Transparency property with applying transparency to images. They are two very different things. In fact, if you enter Transparency at the Command line, AutoCAD assumes the latter and asks you to select an image.
The status bar has a Show/Hide Transparency tool. If you set this button to Hide, the transparent objects appear as if they have no transparency at all. This tool is the one to check if your transparent objects aren't correct.
Plotting and Transparency
I want to discuss one last thing regarding transparency: plotting! By default, AutoCAD doesn't plot transparency. To plot transparent objects, AutoCAD must rasterize the drawing, and that really slows down a plot (hence the default). No need to worry though; if needed, you simply turn on this option when plotting. Press the arrow in the lower right-hand corner of the Plot (or Page Setup) dialog box to expand the list of plot options, and find the toggle for Plot Transparency.
The Transparency toggle does not stay on. If you always need to plot transparencies, you can override this behavior by using a setting of 2 for the PlotTransparencyOverride system variable (possibly the longest system variable name in AutoCAD).
If you have your Visual Style set to Realistic, Conceptual, or Shaded, AutoCAD always plots with transparency (because it has to rasterize the drawing anyway).
Now that object transparency is here, be sure to take advantage of it! You'll find it easy to use — yet a very impressive addition to your drawings. Until next time, Happy AutoCADing!