User guide

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This is achieved in one of two ways when editing .args files:
1. Adding a page attribute with the name of the page to each parameter:
<param name="Kd" page="myPage"/>
2. Grouping parameters using a page tag:
<page name="myPage">
.
.
</page>
TIP: The attribute open can be set to True to expand a group by default. The open hint also works for
group parameters and attributes, which are closed by default. For example:
<page name="Basics" open="True">
NOTE: The shader parameters not explicitly specified in the .args file are displayed last in the Material
node UI.
Co-Shaders
It is a RenderMan convention to specify co-shaders used in a shader interface using parameters of type string or
shader. If specified using type shader, Katana detects that this is a co-shader port automatically. If specified using
type string, you must provide a hint in the .args file.
<param name="Kd_color_mycoshader" coshaderPort="True" />
Co-Shader Pairing
Katana allows co-shaders to be represented as network materials. For user convenience, there is a convention that
allows pairs of parameters, representing a value and a port for a co-shader, to be presented to the user to look like a
single connectable value in the UI.
RenderMan co-shader pairing is used by adding a co-shader port and specifying the co-shader's name in the
coshaderPair attribute of the parameter. In the args file, this is achieved as follows:
<args format="1.0">
<param name="Kd_color_mycoshader" coshaderPort="True" />
<param name="Kd_color"
coshaderPair="Kd_color_mycoshader" widget="color"/>
</args>
20 ARGS FILES IN SHADERS | EDIT SHADER INTERFACE INTERACTIVELY IN THE UI