Merge branch 'AcademySoftwareFoundation:main' into functional_nodedefs

Author: kwokcb

documents/Specification/MaterialX.Specification.md

@@ -99,7 +99,7 @@ Because the same word can be used to mean slightly different things in different
 
 An **Element** is a named object within a MaterialX document, which may possess any number of child elements and attributes.  An **Attribute** is a named property of a MaterialX element.
 
-A **Node** is a function that generates or operates upon spatially-varying data.  This specification provides a set of standard nodes with precise definitions, and also supports the creation of custom nodes for application-specific uses.  The interface for a node’s incoming data is declared through **Inputs**, which may be spatially-varying or uniform, and **Tokens**, which are string values that can be substituted into filenames declared in node inputs.
+A **Node** is a function that generates or operates upon spatially-varying data.  This specification provides a set of standard nodes with precise definitions, and also supports the creation of custom nodes for application-specific uses.  The interface for a node’s incoming data is declared through **Inputs**, which may be spatially-varying or uniform, and **Tokens**, which are string values that can be substituted into filenames declared in node inputs.  The interface for a node's outgoing data is declared through one or more **Outputs**; a node's Inputs, Tokens and Outputs are collectively referred to as the node's **Ports**.
 
 A **Pattern** is a node that generates or processes simple scalar, vector, and color data, and has access to local properties of any geometry that has been bound.
 
@@ -937,7 +937,7 @@ Specific applications will commonly support sources and operators that do not ma
 
 ### Custom Node Declaration NodeDef Elements
 
-Each custom node must be explicitly declared with a <nodedef> element, with child <input>, <token> and <output> elements specifying the expected names and types of the node’s inputs and output(s).
+Each custom node must be explicitly declared with a <nodedef> element, with child <input>, <token> and <output> elements specifying the expected names and types of the node’s ports.
 
 Attributes for <nodedef> elements:
 

libraries/bxdf/translation/standard_surface_to_gltf_pbr.mtlx

@@ -187,6 +187,9 @@
       <input name="in1" type="float" interfacename="sheen_roughness" />
       <input name="in2" type="float" value="0" />
     </ifgreater>
+    <sqrt name="sqrt_sheen_roughness" type="float">
+      <input name="in" type="float" nodename="sheen_roughness" />
+    </sqrt>
 
     <!-- Clearcoat -->
     <ifequal name="clearcoat" type="float">
@@ -257,7 +260,7 @@
     <output name="thickness_out" type="float" nodename="thickness" />
     <output name="attenuation_color_out" type="color3" nodename="attenuation_color" />
     <output name="sheen_color_out" type="color3" nodename="sheen_color" />
-    <output name="sheen_roughness_out" type="float" nodename="sheen_roughness" />
+    <output name="sheen_roughness_out" type="float" nodename="sqrt_sheen_roughness" />
     <output name="clearcoat_out" type="float" nodename="clearcoat" />
     <output name="clearcoat_roughness_out" type="float" nodename="clearcoat_roughness" />
     <output name="emissive_out" type="color3" nodename="emissive" />