This node is used to access the mental ray for Maya user framebuffer functionality.
See the following for more information:
Many features can be controlled by string options, which minimizes parse errors. You can enter the string options through the String Options section in the miDefaultOptions Attribute Editor.
Each item has 3 children name, type, and value, all of type string, which provide the required information for the mental ray option.
You can add more attributes by clicking the Add New Item button and a new item appears.
The following keywords are recognized in the type and value fields: