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On a Render Bender
- Visualizing a 3D model
- Lighting your models
- Applying materials
- Assigning a background
- Rendering a 3D model
In the computer graphics world, rendering is the process of illuminating a set of 3D objects with one or more imaginary lights and then creating a more-or-less realistic picture of the results. (No, computer programmers didn't have lard on their minds when they borrowed the word rendering. Hand-drawn pictures of building facades were called renderings long before computers got into the act.)
A single example of this technique is called a still rendering. Multiple frames strung together produce computer animation. The objects that you see in movies such as WALL-E or Toy Story 3 are first created as 3D models and then rendered frame by frame—a process that can take immense amounts of time even on ultrafast graphics workstations—to produce the beautifully, well-rendered images you see.
AutoCAD is best at creating still renderings. If you want to create photorealistic rendered animations, you need to use other software programs such as Autodesk 3ds Max. Even if you use other animation programs, AutoCAD can still be useful for developing the initial 3D models.
Rendering has steadily improved in speed and usability as PCs have become faster and programmers improved their rendering algorithms. Rendering of simple scenes is now practical on a mainstream PC, and a fast personal computer can create some impressive images in a reasonable amount of time.
Rendered images are useful for previewing how your models will work in real life and also can be powerful tools for sales and marketing communications for your company. A (rendered) picture can be worth quite a bit more than a thousand words.
People who do a lot of rendering and want higher quality, photorealistic results usually use programs other than AutoCAD to render their models. Autodesk 3ds Max, Cinema 4D (Maxon), and AccuRender (Robert McNeel & Associates) are three popular photorealistic rendering programs. Most rendering programs can import 3D models from AutoCAD DWG files, but some people use specialized 3D modeling programs to do their modeling as well.