Autodesk 12812-051462-9011 User Guide 3 - Page 2652

By default, there's no ambient light in a scene. If you examine the darkest shadows on your model with the default ambient light setting, you cannot make out the surface because it's unlit by any light. Shadows in your scene will not appear any darker than the ambient light color, which is why you usually keep ambient light set to black (or a very dark color). If you use photometric lights and a radiosity solution on page 6168, ambient light is accurately calculated. The other advanced lighting option, light tracing on page 6154, also generates ambient lighting. If you use standard lights, a good lighting test is to set your ambient lighting to black (the default), set up all your lights, and then decide at the end if you need to increase the ambient light. Animated Texture An animated texture is a material whose properties change over time. One example of this is assigning a multi-frame bitmap (for example, an AVI file or an IFL image-file sequence) as a map. Animated textures can also be materials with keyframed parameters. In addition, in the context of particle systems, a material that uses the Particle Age map on page 5889 or the Particle MBlur map on page 5891 is considered to be animated. In general, when applying an animated texture to particles in Particle Flow, be sure incorporate it in a Material Dynamic operator on page 2925. Animation Animation is based on a principle of human vision. If you view a series of related still images in quick succession, your brain perceives them as continuous motion. Each image is called a frame. Historically, the major difficulty in creating animations has been that the animator must produce a large number of frames. Depending on the quality you want, one minute of animation might require between 720 and 1800 separate still images. Creating images by hand is a big job. That's where keyframing comes in. Most of the frames in an animation are routine, incremental changes from the previous frame directed toward some predefined goal. Early animation studios quickly realized they could increase the productivity of their master Glossary | 7907