User guide

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https://docs.python.org/2/reference/lexical_analysis.html#identifiers.
What Is A Node?
A typical node is composed of:
• Zero or more input ports, which receive the filter tree from nodes further up the Node Graph.
• Zero or more output ports, responsible for the filter tree onto other nodes.
• A User Interface to configure the behavior of the node.
• Some internal logic that is responsible for creating locations and attributes within the Scene Graph.
In creating a custom node we are concerned with defining:
1. The user interface through which the node's behavior is configured.
2. The internal logic, which is responsible for launching your SGG plug-in.
Defining Your Node Class
The custom nodes you create in Katana are sub-classes of the Node3D class, which belongs to the Nodes3DAPI, so
the first step is to import the required modules to allow us to access this and other required functionality.
Importing Required Modules
from Nodes3DAPI import Node3D
from Katana import NodegraphAPI, GeoAPI
from Katana import PyScenegraphAttr, Utils, AssetAPI
ScenegraphAttr = PyScenegraphAttr
from Nodes3DAPI.TimingUtils import GetModifiedFrameTime
from Nodes3DAPI.TimingUtils import GetTimingParameterXML
from Nodes3DAPI.TimingUtils import GetTimingParameterHints
from Nodes3DAPI.ProceduralSetup import GetProceduralTimeArgs
import logging
15 WRAPPING SGG PLUG-INS IN A CUSTOM NODE | WHAT IS A NODE?