The 2011 release of AutoCAD includes a long desired feature that will greatly benefit cartographers, as well as users in many other disciplines; TRANSPARENCY.
The ability to make any object, layer, hatch pattern, solid fill or image partially transparent, allowing overlapping objects to be seen “through” those transparent objects is a feature many of us have desired for decades. In most 2011 Autodesk products, including Civil 3D and Map 3D, transparency will be one more object property. You can control it by layer (using a new column in the Layer Properties Manager), or by object, just like other properties such as color, lineweight, linetype, etc. You can set the level of transparency anywhere from 0 (invisible) to 90% (nearly opaque). A transparency slider control was added to the Properties panel of the Ribbon Home tab:
You can also control transparency by Viewport, and through both the Quick Properties and Properties palettes, and the transparency value of objects will be displayed with the List command.
Object transparency is often desirable when creating maps. A common need for this long overdue feature is in preparing base maps, such as zoning or population density, where the detail of a street base map is desired, overlaid with subtly colored regions depicting different values. Until the transparency property became available, we typically had to experiment (using a clumsy hit and miss approach) with various hatch patterns and thick borders. Now, we can do it right!