About preview rendering
Before you do a final render, preview the appearance of objects, shaders, textures, and lights using one of the preview renderers. Preview rendering is typically faster (and lower quality) than final rendering.
If you are presenting an initial concept design, you may want your presentation to have a stylish sketched look. You can create this type of image by creating a sketch and a simple model, then using Render > Place Projection 
on a roughed-in model, and using either WindowDisplay > Hardware Shade 
or Render > Direct Render
.
Use Render > Direct Render for preview software renderings.
Direct render
Direct render is a convenient way to launch and monitor one or more renders while working within Alias.
Direct render opens a new window on top of the active window, and renders that window’s view using the selected renderer.
Select one of the following five Alias renderers depending on what option or options you have available with your software:
- Raycaster
- Raytracer
- Hidden Line
- Powercaster
- Powertracer