SketchUp 4.0

At the AIA 2001 National Convention and Expo, I described how the two biggest crowd-pullers at the show were two new products for conceptual building design: SketchUp by start-up company @Last Software and Autodesk Architectural Studio by industry veteran Autodesk (see Cadence AEC Tech News #51). Since then, SketchUp has continued to gain in popularity and momentum, as evidenced by the throngs of show attendees that continue to crowd around its booth at every show, including the recently concluded AIA 2004 Convention and Expo (see AECbytes Newsletter #10). In contrast, Autodesk Architectural Studio wasn't even being very prominently demonstrated at this year's convention. Obviously, @Last Software has been doing something very right, and in this product review, I will not only explore the new features in the latest release of SketchUp but also analyze the reasons behind SketchUp's phenomenal success in the AEC industry.

But first, here's a comprehensive overview of the application for those who are not familiar with it.

Overview of SketchUp

SketchUp is an application for 3D design exploration, which is targeted towards the conceptual phase of design and has specifically been developed to be easy, intuitive, and fun to use. Initially a Windows-based application, it was subsequently also developed for the Mac platform and is now a regular exhibitor at the Macworld conventions. (See AECbytes Newsletter #4 on Macworld 2004.) In fact, the new version, SketchUp 4.0, was officially released at the Macworld show in Boston this week, where it just won a "Best of Show" award.

SketchUp has a minimalist easy-to-learn interface, with most of the screen space devoted to the drawing window. There are only eight toolbars with a limited number of tools in each toolbar (Figure 1 shows all of them). There are no options associated with every tool that need to be accessed in individual dialog boxes; a Preferences dialog contains all the program preferences, and a Model Info dialog contains all the model-specific settings. Additional palettes showing materials, components, layers, and so on can be opened when needed. The Status Bar at the base of the drawing window displays command prompts and status messages and also contains a box for coordinate entry. The emphasis on "less rather than more" makes it possible to get up and running in SketchUp very quickly compared to other CAD, BIM, and 3D modeling applications.

You would start in SketchUp by creating a face using one of the six drawing tools: Line, Arc, Freehand, Rectangle, Circle, or Polygon. Closure is automatically detected by the program. You would then use the Push/Pull tool to apply a pulling operation to convert the face to a 3D object. Further volumes can be added or subtracted from this 3D object by again drawing faces on its surfaces and pulling or pushing them out respectively, using the Push/Pull tool (see Figure 1). All the three axes in SketchUp work identically, which means that you can draw along the z axis just as easily as you can draw along the x or the y axis. The axes are differentiated by color, and drawing a line aligned with an axis temporarily gives it the color of the axis, allowing you to create accurately aligned and oriented objects. An Axes tool is available for repositioning and orienting this coordinate system in any desired direction, allowing you to model accurately anywhere in 3D space. Object snapping is built into the program and does not require the selection of any tool.

In addition to the drawing tools and the Push/Pull tool, SketchUp's repertoire includes the basic functionalities required for any kind of 3D modeling: moving, copying, rotating, scaling, offsetting, and deletion; measuring distances and angles and creating 2D-dashed construction lines; zooming, scrolling, orbiting, turning, and walking through the model; dimensioning and annotation; switching between Top, Right, Iso, and other views; and switching between Wireframe, Hidden Line, Shaded, and other display modes. Entities can be organized into layers, which have only the properties of visibility and color, perfectly adequate for basic modeling requirements. A Paint tool is available to apply the selected color or texture from the Material Browser to a face. SketchUp has quite an extensive library of textures for different building surfaces; additionally, custom textures can also be created from 2D image files. This allows preliminary renderings to be generated within SketchUp itself. For photorealistic renderings, however, the model would have to be exported to a specialized rendering program.

SketchUp also includes many advanced features in its repertoire that make modeling easier and more efficient, without detracting from its basic simplicity. There is a built-in library of predefined components that can be inserted into the model such as doors, windows, furniture, landscape, lighting, people, shapes, and so on (see Figure 2). Components such as doors and windows automatically create openings in the wall in which they are inserted. The Shapes library includes predefined shapes such as cone, cylinder, sphere, dome, and so on, which can be inserted in the default size and then scaled and rotated as required. Other component items such as people, trees, cars, furniture, and so on provide an easy way to add life and vibrancy to an otherwise empty model. Components can be edited in place, and the changes can be dynamically updated in all the components of the same type inserted throughout the model. You can also define your own components from any SketchUp geometry.

Other advanced capabilities include being able to pick a site location and then interactively watch the shadows change as you manipulate the time settings, daily or annually; inserting image files into the model as objects that can be drawn on, which allows, for instance, a building to be designed directly on top of a scanned site plan or aerial photograph; changing the color, brightness, and other settings of a texture image without having to redefine it externally; creating section cuts for looking inside the model and being able to export section slices to a CAD model; and saving different view settings—including a specific time and place for shadows, rendering options, and layer and geometry visibility—as pages that can be played sequentially in a slideshow for presentations within SketchUp itself.

Let's move on to look at the enhancements in the new version, SketchUp 4.0.

New Features in Version 4.0

SketchUp 4.0 has a range of improvements on a variety of fronts. On the modeling front, there are two new capabilities. A new tool called Follow Me has been introduced, which pulls or pushes a surface along a path and can be used to quickly create stair railings, moldings, tubing, and other extruded objects. In this respect, it is similar to the "sweep" or "extrude along path" operation commonly found in other 3D modeling programs. However, Follow Me goes well beyond this basic functionality. As shown in Figure 3, you can use it to draw a profile on one face of an object and then extrude that profile along an entire sequence of connected edges, modifying the shape of the object. Volumes are added to or deleted from the object as necessary. Follow Me can also be used to create revolved shapes. Thus, the single Follow Me tool provides SketchUp users with a range of advanced modeling operations that would be available as multiple tools in other high-end 3D modeling applications.

The second modeling enhancement is the Intersector, which makes up for the absence of dedicated Boolean tools in SketchUp and allows complex geometry to be built up from simple shapes. Provided as an option rather than a tool, the Intersector allows two elements to be intersected and automatically creates new edges where the elements intersect, thus creating new divided surfaces. These surfaces can then be pushed, pulled or deleted to create new geometry.

Previous versions of SketchUp did not have any precise texture mapping capability apart from the ability to specify the size of a texture before placing it. On the rendering front, therefore, the most critical enhancement in SketchUp 4.0 is a new Texture Positioning option, with which the texture placed on a selected face can be adjusted as required. Figure 4 shows the Texture Positioning option in action, with four pins that allow the texture to be moved, scaled and rotated, skewed, and corrected for perspective distortion directly on the surface. A free pin mode is also available which allows the texture to be freely distorted and is particularly useful for modeling geometry in reference to a photograph. Textures and images can now also be wrapped around corners and projected over forms, useful for projecting an image on to a terrain model, for instance.

Another notable enhancement on the rendering and visualization front is a new "Face Me" behavior for 2D entourage components such as people, trees, and vehicles, such as those shown in Figure 2. When this behavior is activated, these components always face the camera irrespective of where the camera is positioned, giving them a 3D look and feel without the overhead of actual 3D entourage models.

For those who believe that no design application is complete without an API (Application Programming Interface) to program and customize it, the new Ruby scripting interface of SketchUp 4.0 will be greatly welcomed. Ruby is an existing programming language, and SketchUp users can use its Ruby API to write macros for performing repetitive tasks, creating pre-defined shapes, and automating the generation of components such as doors, stairs, furniture, etc., based on specified input parameters.

On the interface front, there are several additions and improvements: redesigned menus with a more logical grouping of commands; "modeless behavior" for many dialog boxes so that they can remain open while working on the model; an "Entity Info" dialog box that displays the properties of the selected entities and allows their material and layer to be easily changed; and bolder inference lines that make it easier to determine alignment with an axis when modeling. Common settings such as units, file locations, background colors, and so on can now be saved in templates for convenient re-use. Other enhancements include the ability to view components visually or by name in the Component Browser; new Rectangle tool options for drawing squares and golden sections for classical proportioning; default labels for the Text tool; improved AutoCAD import including support for version 2004; a new Camera Field of View Tool that allows the perspective of the model to be easily modified by dragging the mouse; and a check for invalid geometry that also attempts to fix any problems that are detected.

What Makes SketchUp Tick?

The key factor that has contributed to SketchUp's success is its tremendous ease of use, which makes it accessible to all designers, even those who are not very computer savvy. In contrast, other 3D modeling and visualization software take serious effort to master and their use in a firm is usually restricted to a specialized set of people who have cultivated the necessary proficiency in it. Moreover, SketchUp's simplicity does not come merely from a stripped-out set of 3D modeling features but from the development of some very innovative ideas of how 3D modeling can be made easier and more intuitive. The application actually incorporates some very complex inference algorithms that constantly look for alignments, snapping, and directions based on the mouse movements, minimizing the input that is needed from the user to perform modeling operations. What also makes the program very attractive to designers, even the "old school" ones who prefer hand drawings to computer-generated visualizations, is that it feels very sketch-like, thanks to innovative display features such as jitter lines, edge extensions, and profiles (see Figure 5).

At a price tag of $495, the program is also very affordable for most design firms. @Last Software has wisely refrained from increasing the price of the application, which has been about the same since it was introduced. Of course, SketchUp cannot be a complete substitute for detailed, precise 3D modeling and highly photorealistic rendering applications such as form•Z and Autodesk VIZ that are popular in the AEC industry. But when the need is primarily for conceptual 3D design, SketchUp is hard to beat from a price as well as performance perspective.

SketchUp has also positioned itself well in the upcoming BIM scenario by providing plug-ins for Autodesk Architectural Desktop and ArchiCAD that can translate the geometry developed in SketchUp to the model-based building components of these BIM applications. While this translation takes some effort and doesn't work flawlessly, it is the beginning of integrating the popular conceptual design capabilities of SketchUp with the advanced building modeling capabilities required for detailed design and documentation. We will probably see SketchUp plug-ins eventually for the other BIM applications as well, and the translation should get easier and more accurate. At a time when other non-AEC specific 3D applications stand the risk of becoming redundant, SketchUp is on its way to carving a secure niche for itself in a BIM-enabled workflow, despite not being a building-specific product.

Going forward, the key challenge before @Last Software is to continue to retain the simplicity, "fun to use" spirit, and low price of the product while adding new features and capabilities. So far, as evident in the latest release of SketchUp 4.0, it has succeeded in doing so remarkably well. It is heartening to see a small company develop a truly innovative product and emerge so successful in a relatively short span of time. The SketchUp story is a very inspiring one for entrepreneurs in general and particularly for other startup companies in the AEC industry.

About the Author

Lachmi Khemlani is founder and editor of AECbytes. She has a Ph.D. in Architecture from UC Berkeley, specializing in intelligent building modeling, and consults and writes on AEC technology. She can be reached at lachmi@aecbytes.com.