I recently downloaded and played around with a neat 3D modeling tool called Sketchup
. @Last Software's SketchUp is a 3D modeling package intended to be used by architects and designers who need to quickly outline 3D ideas, but don't care for the difficulty of a CAD program, or the advanced features of a high-end 3D modeler.
SketchUp's toolset is fairly simple, offering a Photoshop-like, two-column tool palette. SketchUp has also a very helpful grid guidance system, with multiple colors to guide you through the 3D orientation plans. Layers can have assigned colors that enable the user to see layer assignments in the model. This feature is helpful because the user can identify model modifications in geometry easily through this interface. For example, if a surface is modified, with one of the tools such as the push/pull, tool, all the planes adjacent to the customized surfaces also change.
Planners and architects can benefit greatly from the "Urban Model"-feature by constructing basic buildings to their appropriate dimensions. Using "push/pull"-functions you can move surfaces increasing or reducing the building footprint. Slap on textures and you have a semi-realistic looking model. I downloaded the demo software and was up and running without much instruction - ended up building a decent looking replica of our old Victorian house house. With past work in the field of energy efficiency and renewable energy I was particularly excited to discover Sketchup's feature that allows visualizing the shadow created by a building or model. The time of day for shadow casting can be set, including day of the year and daytime.
Most importantly, in my mind, the new release allows the user to export directly into ArcGIS 9's visualization extension. This means planners and GIS users now have an easy to use tool to bring buildings into their 3D analyst fly-throughs.