From 56d71e140acf5ad0888383b6ec8cacad5bd0b299 Mon Sep 17 00:00:00 2001
From: Lee Kerley <ld_kerley@icloud.com>
Date: Wed, 20 May 2026 17:40:28 -0700
Subject: [PATCH 1/3] Add UsdUVTexture v2.3 variant with vector4 scale and bias

Introduces ND_UsdUVTexture_23_vector4 nodedef and IMP_UsdUVTexture_23_vector4
nodegraph implementation, where the `scale` and `bias` inputs are typed as
vector4 instead of the original color4-derived behavior. The prior variant is
retained for now and may be removed in a future MaterialX release via an
upgrade function.
---
 libraries/bxdf/usd_preview_surface.mtlx | 52 +++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/libraries/bxdf/usd_preview_surface.mtlx b/libraries/bxdf/usd_preview_surface.mtlx
index f89e561c3d..8c0421f726 100644
--- a/libraries/bxdf/usd_preview_surface.mtlx
+++ b/libraries/bxdf/usd_preview_surface.mtlx
@@ -50,6 +50,23 @@
     <output name="rgb" type="color3" />
   </nodedef>
 
+  <!-- adding variant with scale and bias defined as vector4 type - we may decide to remove the original version
+    in a future MaterialX version with an upgrade function -->
+  <nodedef name="ND_UsdUVTexture_23_vector4" node="UsdUVTexture" nodegroup="texture2d" version="2.3">
+    <input name="file" type="filename" value="" uniform="true" />
+    <input name="st" type="vector2" defaultgeomprop="UV0" />
+    <input name="wrapS" type="string" value="periodic" enum="black,clamp,periodic,mirror" uniform="true" />
+    <input name="wrapT" type="string" value="periodic" enum="black,clamp,periodic,mirror" uniform="true" />
+    <input name="fallback" type="color4" value="0, 0, 0, 1" />
+    <input name="scale" type="vector4" value="1, 1, 1, 1" uniform="true" />
+    <input name="bias" type="vector4" value="0, 0, 0, 0" uniform="true" />
+    <output name="r" type="float" />
+    <output name="g" type="float" />
+    <output name="b" type="float" />
+    <output name="a" type="float" />
+    <output name="rgb" type="color3" />
+  </nodedef>
+
   <!-- Node: UsdPrimvarReader -->
   <nodedef name="ND_UsdPrimvarReader_integer" nodegroup="geometric" node="UsdPrimvarReader">
     <input name="varname" type="string" value="" uniform="true" />
@@ -371,6 +388,41 @@
     <output name="rgb" type="color3" nodename="image_bias_color3" />
   </nodegraph>
 
+  <nodegraph name="IMP_UsdUVTexture_23_vector4" nodedef="ND_UsdUVTexture_23_vector4">
+    <image name="image_reader" type="color4">
+      <input name="file" type="filename" interfacename="file" />
+      <input name="default" type="color4" interfacename="fallback" />
+      <input name="texcoord" type="vector2" interfacename="st" />
+      <input name="uaddressmode" type="string" interfacename="wrapS" />
+      <input name="vaddressmode" type="string" interfacename="wrapT" />
+    </image>
+    <convert name="convert_vector4" type="vector4">
+      <input name="in" type="color4" nodename="image_reader" />
+    </convert>
+    <multiply name="image_scale" type="vector4">
+      <input name="in1" type="vector4" nodename="convert_vector4" />
+      <input name="in2" type="vector4" interfacename="scale" />
+    </multiply>
+    <add name="image_bias" type="vector4">
+      <input name="in1" type="vector4" nodename="image_scale" />
+      <input name="in2" type="vector4" interfacename="bias" />
+    </add>
+    <convert name="comvert_color4" type="color4">
+      <input name="in" type="vector4" nodename="image_bias" />
+    </convert>
+    <separate4 name="image_bias_separate" type="multioutput" nodedef="ND_separate4_color4">
+      <input name="in" type="color4" nodename="comvert_color4" />
+    </separate4>
+    <convert name="image_bias_color3" type="color3">
+      <input name="in" type="color4" nodename="comvert_color4" />
+    </convert>
+    <output name="r" type="float" nodename="image_bias_separate" output="outr" />
+    <output name="g" type="float" nodename="image_bias_separate" output="outg" />
+    <output name="b" type="float" nodename="image_bias_separate" output="outb" />
+    <output name="a" type="float" nodename="image_bias_separate" output="outa" />
+    <output name="rgb" type="color3" nodename="image_bias_color3" />
+  </nodegraph>
+
   <!-- Node: UsdPrimvarReader -->
   <nodegraph name="IMP_UsdPrimvarReader_integer" nodedef="ND_UsdPrimvarReader_integer">
     <geompropvalue name="primvar" type="integer">

From b3d765bafbf8e53935a110238f04b637ef080c08 Mon Sep 17 00:00:00 2001
From: Lee Kerley <ld_kerley@icloud.com>
Date: Wed, 27 May 2026 22:14:43 -0700
Subject: [PATCH 2/3] add extra unit test - and fix up default version tagging
 - so both of the nodedefs with the new version can be selected

---
 libraries/bxdf/usd_preview_surface.mtlx        |  2 +-
 .../usd_preview_surface_brass.mtlx             | 17 +++++++++++++++++
 ...usd_preview_surface_brass_vector_scale.mtlx | 18 ++++++++++++++++++
 3 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass.mtlx
 create mode 100644 resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_vector_scale.mtlx

diff --git a/libraries/bxdf/usd_preview_surface.mtlx b/libraries/bxdf/usd_preview_surface.mtlx
index 8c0421f726..b1420745e2 100644
--- a/libraries/bxdf/usd_preview_surface.mtlx
+++ b/libraries/bxdf/usd_preview_surface.mtlx
@@ -52,7 +52,7 @@
 
   <!-- adding variant with scale and bias defined as vector4 type - we may decide to remove the original version
     in a future MaterialX version with an upgrade function -->
-  <nodedef name="ND_UsdUVTexture_23_vector4" node="UsdUVTexture" nodegroup="texture2d" version="2.3">
+  <nodedef name="ND_UsdUVTexture_23_vector4" node="UsdUVTexture" nodegroup="texture2d" version="2.3" isdefaultversion="true">
     <input name="file" type="filename" value="" uniform="true" />
     <input name="st" type="vector2" defaultgeomprop="UV0" />
     <input name="wrapS" type="string" value="periodic" enum="black,clamp,periodic,mirror" uniform="true" />
diff --git a/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass.mtlx b/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass.mtlx
new file mode 100644
index 0000000000..f18e2326df
--- /dev/null
+++ b/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass.mtlx
@@ -0,0 +1,17 @@
+<?xml version="1.0"?>
+<materialx version="1.39" colorspace="lin_rec709">
+  <UsdUVTexture name="image_color" type="multioutput">
+    <input name="file" type="filename" value="../../../Images/brass_color.jpg" colorspace="srgb_texture" />
+  </UsdUVTexture>
+  <UsdUVTexture name="image_roughness" type="multioutput">
+    <input name="file" type="filename" value="../../../Images/brass_roughness.jpg" />
+  </UsdUVTexture>
+  <UsdPreviewSurface name="SR_brass1" type="surfaceshader">
+    <input name="diffuseColor" type="color3" nodename="image_color" output="rgb" />
+    <input name="metallic" type="float" value="1" />
+    <input name="roughness" type="float" nodename="image_roughness" output="r" />
+  </UsdPreviewSurface>
+  <surfacematerial name="USD_Tiled_Brass" type="material">
+    <input name="surfaceshader" type="surfaceshader" nodename="SR_brass1" />
+  </surfacematerial>
+</materialx>
diff --git a/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_vector_scale.mtlx b/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_vector_scale.mtlx
new file mode 100644
index 0000000000..8bafc9b735
--- /dev/null
+++ b/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_vector_scale.mtlx
@@ -0,0 +1,18 @@
+<?xml version="1.0"?>
+<materialx version="1.39" colorspace="lin_rec709">
+  <UsdUVTexture name="image_color" type="multioutput">
+    <input name="file" type="filename" value="../../../Images/brass_color.jpg" colorspace="srgb_texture" />
+    <input name="scale" type="vector4" value="0.5, 0.5, 0.5, 1" />
+  </UsdUVTexture>
+  <UsdUVTexture name="image_roughness" type="multioutput">
+    <input name="file" type="filename" value="../../../Images/brass_roughness.jpg" />
+  </UsdUVTexture>
+  <UsdPreviewSurface name="SR_brass1" type="surfaceshader">
+    <input name="diffuseColor" type="color3" nodename="image_color" output="rgb" />
+    <input name="metallic" type="float" value="1" />
+    <input name="roughness" type="float" nodename="image_roughness" output="r" />
+  </UsdPreviewSurface>
+  <surfacematerial name="USD_Tiled_Brass" type="material">
+    <input name="surfaceshader" type="surfaceshader" nodename="SR_brass1" />
+  </surfacematerial>
+</materialx>

From 98615056b02bda21234c23de1ebde3652e0aa5ef Mon Sep 17 00:00:00 2001
From: Lee Kerley <ld_kerley@icloud.com>
Date: Thu, 28 May 2026 08:28:25 -0700
Subject: [PATCH 3/3] Updating unit tests

---
 .../usd_preview_surface_brass.mtlx            | 17 ----------
 .../usd_preview_surface_brass_tiled.mtlx      | 32 +++++++++++++++++++
 ...sd_preview_surface_brass_vector_scale.mtlx | 18 -----------
 3 files changed, 32 insertions(+), 35 deletions(-)
 delete mode 100644 resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass.mtlx
 delete mode 100644 resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_vector_scale.mtlx

diff --git a/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass.mtlx b/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass.mtlx
deleted file mode 100644
index f18e2326df..0000000000
--- a/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass.mtlx
+++ /dev/null
@@ -1,17 +0,0 @@
-<?xml version="1.0"?>
-<materialx version="1.39" colorspace="lin_rec709">
-  <UsdUVTexture name="image_color" type="multioutput">
-    <input name="file" type="filename" value="../../../Images/brass_color.jpg" colorspace="srgb_texture" />
-  </UsdUVTexture>
-  <UsdUVTexture name="image_roughness" type="multioutput">
-    <input name="file" type="filename" value="../../../Images/brass_roughness.jpg" />
-  </UsdUVTexture>
-  <UsdPreviewSurface name="SR_brass1" type="surfaceshader">
-    <input name="diffuseColor" type="color3" nodename="image_color" output="rgb" />
-    <input name="metallic" type="float" value="1" />
-    <input name="roughness" type="float" nodename="image_roughness" output="r" />
-  </UsdPreviewSurface>
-  <surfacematerial name="USD_Tiled_Brass" type="material">
-    <input name="surfaceshader" type="surfaceshader" nodename="SR_brass1" />
-  </surfacematerial>
-</materialx>
diff --git a/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_tiled.mtlx b/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_tiled.mtlx
index 85f6f3e139..78cce9aad8 100644
--- a/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_tiled.mtlx
+++ b/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_tiled.mtlx
@@ -20,4 +20,36 @@
   <surfacematerial name="USD_Tiled_Brass" type="material">
     <input name="surfaceshader" type="surfaceshader" nodename="SR_brass1" />
   </surfacematerial>
+
+  <UsdUVTexture name="image_color" type="multioutput">
+    <input name="file" type="filename" value="../../../Images/brass_color.jpg" colorspace="srgb_texture" />
+  </UsdUVTexture>
+  <UsdUVTexture name="image_roughness" type="multioutput">
+    <input name="file" type="filename" value="../../../Images/brass_roughness.jpg" />
+  </UsdUVTexture>
+  <UsdPreviewSurface name="SR_brass" type="surfaceshader">
+    <input name="diffuseColor" type="color3" nodename="image_color" output="rgb" />
+    <input name="metallic" type="float" value="1" />
+    <input name="roughness" type="float" nodename="image_roughness" output="r" />
+  </UsdPreviewSurface>
+  <surfacematerial name="USD_Brass" type="material">
+    <input name="surfaceshader" type="surfaceshader" nodename="SR_brass" />
+  </surfacematerial>
+
+  <UsdUVTexture name="image_color_scaled" type="multioutput">
+    <input name="file" type="filename" value="../../../Images/brass_color.jpg" colorspace="srgb_texture" />
+    <input name="scale" type="vector4" value="0.5, 0.5, 0.5, 1" />
+  </UsdUVTexture>
+  <UsdUVTexture name="image_roughness_bias" type="multioutput">
+    <input name="file" type="filename" value="../../../Images/brass_roughness.jpg" />
+    <input name="bias" type="vector4" value="0.2, 0.2, 0.2, 0" />
+  </UsdUVTexture>
+  <UsdPreviewSurface name="SR_brass_scale_bias" type="surfaceshader">
+    <input name="diffuseColor" type="color3" nodename="image_color_scaled" output="rgb" />
+    <input name="metallic" type="float" value="1" />
+    <input name="roughness" type="float" nodename="image_roughness" output="r" />
+  </UsdPreviewSurface>
+  <surfacematerial name="USD_Brass_scale_bias" type="material">
+    <input name="surfaceshader" type="surfaceshader" nodename="SR_brass_scale_bias" />
+  </surfacematerial>
 </materialx>
diff --git a/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_vector_scale.mtlx b/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_vector_scale.mtlx
deleted file mode 100644
index 8bafc9b735..0000000000
--- a/resources/Materials/Examples/UsdPreviewSurface/usd_preview_surface_brass_vector_scale.mtlx
+++ /dev/null
@@ -1,18 +0,0 @@
-<?xml version="1.0"?>
-<materialx version="1.39" colorspace="lin_rec709">
-  <UsdUVTexture name="image_color" type="multioutput">
-    <input name="file" type="filename" value="../../../Images/brass_color.jpg" colorspace="srgb_texture" />
-    <input name="scale" type="vector4" value="0.5, 0.5, 0.5, 1" />
-  </UsdUVTexture>
-  <UsdUVTexture name="image_roughness" type="multioutput">
-    <input name="file" type="filename" value="../../../Images/brass_roughness.jpg" />
-  </UsdUVTexture>
-  <UsdPreviewSurface name="SR_brass1" type="surfaceshader">
-    <input name="diffuseColor" type="color3" nodename="image_color" output="rgb" />
-    <input name="metallic" type="float" value="1" />
-    <input name="roughness" type="float" nodename="image_roughness" output="r" />
-  </UsdPreviewSurface>
-  <surfacematerial name="USD_Tiled_Brass" type="material">
-    <input name="surfaceshader" type="surfaceshader" nodename="SR_brass1" />
-  </surfacematerial>
-</materialx>