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Specifies the name of the attribute that corresponds to this parameter. There are many reasons to use these attribute - parameter mapping: because the software or OSL imposes restrictions (e.g. an attribute named "color" in Maya, which is a reserved word in OSL), because the shader has different parameter naming conventions than what is expected in the software, or because the required attribute in the software is part of a complex attribute structure that does not have an OSL counterpart.
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When none of the above metadata are provided, the parameter name is used directly to define the attribute name.
string niceName
Maya-specific
Specifies the attribute name to use in the user interface, when possible. This will be used in the Maya editors, notably the Node Editor and the Channel Box. It will also be used for the automatically generated Attribute Editor template, unless label is specified.
string label
Specifies the label of the widget that controls the attribute.
string maya_type
Specifies the type of the Maya attribute related to the shader parameter. For now, only bool is supported to display an integer parameter as a checkbox.
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