update mtlx spec version and minor fixes

Author: krohmerNV

source/MaterialXGenMdl/mdl/materialx/pbrlib.mdl

@@ -16,15 +16,15 @@
 
 // MDL implementation of all types and nodes of
 //     MaterialX Physically-Based Shading Nodes
-//     Document v1.37 REV2, July 16, 2019 (Revised October 17, 2019)
+//     Document version 1.39, June 29, 2024
 //     see www.materialx.org 
 // in
-//     NVIDIA Material Definition Language 1.8
+//     NVIDIA Material Definition Language 1.9
 //     Language Specification
-//     Document version 1.8.2, May 24, 2023
+//     Document version 1.9.2, September 16, 2024
 //     www.nvidia.com/mdl
 
-mdl 1.8;
+mdl 1.9;
 
 // forward the latest version
-export using .::pbrlib_1_8 import *;
+export using .::pbrlib_1_9 import *;

source/MaterialXGenMdl/mdl/materialx/pbrlib_1_9.mdl

@@ -16,7 +16,7 @@
 
 // MDL implementation of all types and nodes of
 //     MaterialX Physically-Based Shading Nodes
-//     Document v1.37 REV2, July 16, 2019 (Revised October 17, 2019)
+//     Document version 1.39, June 29, 2024
 //     see www.materialx.org 
 // in
 //     NVIDIA Material Definition Language 1.9
@@ -369,4 +369,4 @@ export material mx_surface(
     geometry: material_geometry(
         cutout_opacity: mxp_opacity
     )
-);
+);

source/MaterialXGenMdl/mdl/materialx/stdlib.mdl

@@ -4,15 +4,15 @@
 //
 // MDL implementation of all Standard Source Nodes of
 //     MaterialX: An Open Standard for Network-Based CG Object Looks
-//     Document v1.37 REV2, January 19, 2020
+//     Document version 1.39, September 15, 2024
 //     www.materialx.org 
 // in
-//     NVIDIA Material Definition Language 1.7
+//     NVIDIA Material Definition Language 1.9
 //     Language Specification
-//     Document version 1.7.2, January 17, 2022
+//     Document version 1.9.2, September 16, 2024
 //     www.nvidia.com/mdl
 
-mdl 1.8;
+mdl 1.9;
 
 // forward the latest version
-export using .::stdlib_1_8 import *;
+export using .::stdlib_1_9 import *;

source/MaterialXGenMdl/mdl/materialx/stdlib_1_9.mdl

@@ -4,7 +4,7 @@
 //
 // MDL implementation of all Standard Source Nodes of
 //     MaterialX: An Open Standard for Network-Based CG Object Looks
-//     Document v1.37 REV2, January 19, 2020
+//     Document version 1.39, September 15, 2024
 //     www.materialx.org 
 // in
 //     NVIDIA Material Definition Language 1.9