Adding Key Functions to the Container

Add a key function to the background container.
Click the key icon to open the key editor.
- For Viz Artist 3.x: Click the Built Ins button, and select Function Container from the drop-list. The Alpha function is in the Global folder.
- For Viz Artist 2.x: Click the Function button.
The key for the background must have the Alpha as key only setting enabled; this prevents a "dirty" key if the background has some level of transparency.
Set Render mode to Blend.
Add a key function to the front_objects container. The Alpha as key only setting must be disabled, and Render mode must be set to Add, to prevent foreground objects from creating a hole in the background object's key signal.

Viz Trio User Guide