Update normalmap node to 1.39 (#1911)

- I have added the null-check from GLSL and MSL to the OSL and MDL backends for consistency. As an alternative, it could be removed from all implementations.

- Tangent vector renormalization in OSL seems like a concern that should be handled by the implementation providing the geometry streams. I removed it.

libraries/stdlib/genglsl/mx_normalmap.glsl

@@ -1,21 +1,13 @@
-void mx_normalmap_vector2(vec3 value, int map_space, vec2 normal_scale, vec3 N, vec3 T,  out vec3 result)
+void mx_normalmap_vector2(vec3 value, vec2 normal_scale, vec3 N, vec3 T, vec3 B, out vec3 result)
 {
-    // Decode the normal map.
-    value = (value == vec3(0.0f)) ? vec3(0.0, 0.0, 1.0) : value * 2.0 - 1.0;
+    value = (value == vec3(0.0)) ? vec3(0.0, 0.0, 1.0) : value * 2.0 - 1.0;
 
-    // Transform from tangent space if needed.
-    if (map_space == 0)
-    {
-        vec3 B = normalize(cross(N, T));
-        value.xy *= normal_scale;
-        value = T * value.x + B * value.y + N * value.z;
-    }
+    value = T * value.x * normal_scale.x + B * value.y * normal_scale.y + N * value.z;
 
-    // Normalize the result.
     result = normalize(value);
 }
 
-void mx_normalmap_float(vec3 value, int map_space, float normal_scale, vec3 N, vec3 T,  out vec3 result)
+void mx_normalmap_float(vec3 value, float normal_scale, vec3 N, vec3 T, vec3 B, out vec3 result)
 {
-    mx_normalmap_vector2(value, map_space, vec2(normal_scale), N, T, result);
+    mx_normalmap_vector2(value, vec2(normal_scale), N, T, B, result);
 }

libraries/stdlib/genmdl/stdlib_genmdl_impl.mtlx

@@ -44,8 +44,8 @@
   <!-- <triplanarprojection> -->
 
   <!-- <normalmap> -->
-  <implementation name="IM_normalmap_float_genmdl" nodedef="ND_normalmap_float" sourcecode="materialx::stdlib_{{MDL_VERSION_SUFFIX}}::mx_normalmap_float(mxp_in:{{in}}, mxp_space:{{space}}, mxp_scale:{{scale}}, mxp_normal:{{normal}}, mxp_tangent:{{tangent}})" target="genmdl" />
-  <implementation name="IM_normalmap_vector2_genmdl" nodedef="ND_normalmap_vector2" sourcecode="materialx::stdlib_{{MDL_VERSION_SUFFIX}}::mx_normalmap_vector2(mxp_in:{{in}}, mxp_space:{{space}}, mxp_scale:{{scale}}, mxp_normal:{{normal}}, mxp_tangent:{{tangent}})" target="genmdl" />
+  <implementation name="IM_normalmap_float_genmdl" nodedef="ND_normalmap_float" sourcecode="materialx::stdlib_{{MDL_VERSION_SUFFIX}}::mx_normalmap_float(mxp_in:{{in}}, mxp_scale:{{scale}}, mxp_normal:{{normal}}, mxp_tangent:{{tangent}}, mxp_bitangent:{{bitangent}})" target="genmdl" />
+  <implementation name="IM_normalmap_vector2_genmdl" nodedef="ND_normalmap_vector2" sourcecode="materialx::stdlib_{{MDL_VERSION_SUFFIX}}::mx_normalmap_vector2(mxp_in:{{in}}, mxp_scale:{{scale}}, mxp_normal:{{normal}}, mxp_tangent:{{tangent}}, mxp_bitangent:{{bitangent}})" target="genmdl" />
 
   <!-- ======================================================================== -->
   <!-- Procedural nodes                                                         -->

libraries/stdlib/genmsl/mx_normalmap.metal

@@ -1,21 +1,13 @@
-void mx_normalmap_vector2(vec3 value, int map_space, vec2 normal_scale, vec3 N, vec3 T,  out vec3 result)
+void mx_normalmap_vector2(vec3 value, vec2 normal_scale, vec3 N, vec3 T, vec3 B, out vec3 result)
 {
-    // Decode the normal map.
-    value = all(value == vec3(0.0f)) ? vec3(0.0, 0.0, 1.0) : value * 2.0 - 1.0;
+    value = all(value == vec3(0.0)) ? vec3(0.0, 0.0, 1.0) : value * 2.0 - 1.0;
 
-    // Transform from tangent space if needed.
-    if (map_space == 0)
-    {
-        vec3 B = normalize(cross(N, T));
-        value.xy *= normal_scale;
-        value = T * value.x + B * value.y + N * value.z;
-    }
+    value = T * value.x * normal_scale.x + B * value.y * normal_scale.y + N * value.z;
 
-    // Normalize the result.
     result = normalize(value);
 }
 
-void mx_normalmap_float(vec3 value, int map_space, float normal_scale, vec3 N, vec3 T,  out vec3 result)
+void mx_normalmap_float(vec3 value, float normal_scale, vec3 N, vec3 T, vec3 B, out vec3 result)
 {
-    mx_normalmap_vector2(value, map_space, vec2(normal_scale), N, T, result);
+    mx_normalmap_vector2(value, vec2(normal_scale), N, T, B, result);
 }

libraries/stdlib/genosl/mx_normalmap.osl

@@ -1,22 +1,19 @@
-void mx_normalmap_vector2(vector value, string map_space, vector2 normal_scale, vector N, vector U, output vector result)
+void mx_normalmap_vector2(vector value, vector2 normal_scale, vector N, vector T, vector B, output vector result)
 {
-    // Tangent space
-    if (map_space == "tangent")
+    vector decodedValue;
+    if (value == vector(0.0))
     {
-        vector v = value * 2.0 - 1.0;
-        vector T = normalize(U - dot(U, N) * N);
-        vector B = normalize(cross(N, T));
-        result = normalize(T * v[0] * normal_scale.x + B * v[1] * normal_scale.y + N * v[2]);
+        decodedValue = vector(0.0, 0.0, 1.0);
     }
-    // Object space
     else
     {
-        vector n = value * 2.0 - 1.0;
-        result = normalize(n);
+        decodedValue = value * 2.0 - 1.0;
     }
+
+    result = normalize(T * decodedValue[0] * normal_scale.x + B * decodedValue[1] * normal_scale.y + N * decodedValue[2]);
 }
 
-void mx_normalmap_float(vector value, string map_space, float normal_scale, vector N, vector U, output vector result)
+void mx_normalmap_float(vector value, float normal_scale, vector N, vector T, vector B, output vector result)
 {
-    mx_normalmap_vector2(value, map_space, vector2(normal_scale, normal_scale), N, U, result);
+    mx_normalmap_vector2(value, vector2(normal_scale, normal_scale), N, T, B, result);
 }

libraries/stdlib/stdlib_defs.mtlx

@@ -2604,18 +2604,18 @@
   -->
   <nodedef name="ND_normalmap_float" node="normalmap" nodegroup="math">
     <input name="in" type="vector3" value="0.5, 0.5, 1.0" />
-    <input name="space" type="string" value="tangent" enum="tangent, object" uniform="true" />
     <input name="scale" type="float" value="1.0" />
     <input name="normal" type="vector3" defaultgeomprop="Nworld" />
     <input name="tangent" type="vector3" defaultgeomprop="Tworld" />
+    <input name="bitangent" type="vector3" defaultgeomprop="Bworld" />
     <output name="out" type="vector3" defaultinput="normal" />
   </nodedef>
   <nodedef name="ND_normalmap_vector2" node="normalmap" nodegroup="math">
     <input name="in" type="vector3" value="0.5, 0.5, 1.0" />
-    <input name="space" type="string" value="tangent" enum="tangent, object" uniform="true" />
     <input name="scale" type="vector2" value="1.0, 1.0" />
     <input name="normal" type="vector3" defaultgeomprop="Nworld" />
     <input name="tangent" type="vector3" defaultgeomprop="Tworld" />
+    <input name="bitangent" type="vector3" defaultgeomprop="Bworld" />
     <output name="out" type="vector3" defaultinput="normal" />
   </nodedef>
 

resources/Materials/TestSuite/pbrlib/surfaceshader/normalmapped_surfaceshader.mtlx

@@ -15,7 +15,6 @@
     <normalmap name="normalmap" type="vector3">
       <input name="in" type="vector3" nodename="tiledimage" />
       <input name="scale" type="float" value="1.1" />
-      <input name="space" type="string" value="tangent" />
     </normalmap>
     <tiledimage name="tiledimage" type="vector3">
       <input name="file" type="filename" value="resources/images/mesh_wire_norm.png" />
@@ -40,7 +39,6 @@
     <normalmap name="normalmap_vector2" type="vector3">
       <input name="in" type="vector3" nodename="tiledimage2" />
       <input name="scale" type="vector2" value="1.1, 1.1" />
-      <input name="space" type="string" value="tangent" />
     </normalmap>
     <tiledimage name="tiledimage2" type="vector3">
       <input name="file" type="filename" value="resources/images/mesh_wire_norm.png" />

resources/Materials/TestSuite/pbrlib/surfaceshader/usd_normal_map.mtlx

@@ -14,7 +14,6 @@
   </convert>
   <normalmap name="N_normalmap" type="vector3">
     <input name="in" type="vector3" nodename="N_convert" />
-    <input name="space" type="string" value="object" />
   </normalmap>
   <UsdPreviewSurface name="N_surface" type="surfaceshader">
     <input name="normal" type="vector3" nodename="N_normalmap" />

resources/Materials/TestSuite/stdlib/color_management/color3_vec3_cm_test.mtlx

@@ -26,7 +26,6 @@
     <normalmap name="impl_normalmap" type="vector3">
       <input name="in" type="vector3" nodename="c3tov3" />
       <input name="scale" type="float" value="1.5" />
-      <input name="space" type="string" value="tangent" />
     </normalmap>
     <output name="normal_map_output" type="vector3" nodename="impl_normalmap" />
   </nodegraph>

resources/Materials/TestSuite/stdlib/definition/definition_using_definitions.mtlx

@@ -274,7 +274,6 @@
     <normalmap name="impl_normalmap" type="vector3">
       <input name="in" type="vector3" nodename="b_image_invert_y" />
       <input name="scale" type="float" interfacename="normal_scale" />
-      <input name="space" type="string" value="tangent" />
     </normalmap>
     <output name="out" type="vector3" nodename="impl_normalmap" />
   </nodegraph>

source/MaterialXCore/Version.cpp

@@ -1316,10 +1316,28 @@ void Document::upgradeVersion()
                     input2->setName("inx");
                 }
             }
-            else if (node->getNodeDefString() == "ND_normalmap")
+            else if (nodeCategory == "normalmap")
             {
                 // ND_normalmap was renamed to ND_normalmap_float
                 node->setNodeDefString("ND_normalmap_float");
+
+                node->removeInput("space");
+
+                // If the normal or tangent inputs are set, the bitangent input should be normalize(cross(N, T))
+                InputPtr normalInput = node->getInput("normal");
+                InputPtr tangentInput = node->getInput("tangent");
+                if (normalInput || tangentInput)
+                {
+                    GraphElementPtr graph = node->getAncestorOfType<GraphElement>();
+                    NodePtr crossNode = graph->addNode("crossproduct", graph->createValidChildName("normalmap_cross"), "vector3");
+                    copyInputWithBindings(node, "normal", crossNode, "in1");
+                    copyInputWithBindings(node, "tangent", crossNode, "in2");
+
+                    NodePtr normalizeNode = graph->addNode("normalize", graph->createValidChildName("normalmap_cross_norm"), "vector3");
+                    normalizeNode->addInput("in", "vector3")->setConnectedNode(crossNode);
+
+                    node->addInput("bitangent", "vector3")->setConnectedNode(normalizeNode);
+                }
             }
         }
         for (NodePtr node : unusedNodes)

source/MaterialXGenMdl/mdl/materialx/stdlib_1_6.mdl

@@ -2094,46 +2094,32 @@ export float4 mx_transformmatrix_vector4(
 
 export float3 mx_normalmap_vector2(
 	float3 mxp_in = float3(0.5, 0.5, 1.0),
-	uniform string mxp_space = string("tangent")
-	[[
-		anno::description("Enumeration {tangent, object}.")
-	]],
 	float2 mxp_scale = float2(1.0, 1.0),
 	float3 mxp_normal = float3(::state::transform_normal(::state::coordinate_internal,::state::coordinate_world,::state::normal())),
-	float3 mxp_tangent = float3(state::transform_vector(::state::coordinate_internal,::state::coordinate_world,::state::texture_tangent_u(0)))
+	float3 mxp_tangent = float3(state::transform_vector(::state::coordinate_internal,::state::coordinate_world,::state::texture_tangent_u(0))),
+	float3 mxp_bitangent = float3(state::transform_vector(::state::coordinate_internal,::state::coordinate_world,::state::texture_tangent_v(0)))
 )
 	[[
 		anno::description("Node Group: math")
 	]]
 {
-	if (mxp_space == "tangent")
-	{
-		float3 v = mxp_in * 2.0 - 1.0;
-		float3 binormal = ::math::normalize(::math::cross(mxp_normal, mxp_tangent));
-		return ::math::normalize(mxp_tangent * v.x * mxp_scale.x + binormal * v.y * mxp_scale.y + mxp_normal * v.z);
-	}
-	else
-	{
-		float3 n = mxp_in * 2.0 - 1.0;
-		return ::math::normalize(n);
-	}
+	float3 v = (mxp_in == float3(0.0)) ? float3(0.0, 0.0, 1.0) : mxp_in * 2.0 - 1.0;
+
+	return ::math::normalize(mxp_tangent * v.x * mxp_scale.x + mxp_bitangent * v.y * mxp_scale.y + mxp_normal * v.z);
 }
 
 export float3 mx_normalmap_float(
 	float3 mxp_in = float3(0.5, 0.5, 1.0),
-	uniform string mxp_space = string("tangent")
-	[[
-		anno::description("Enumeration {tangent, object}.")
-	]],
 	float mxp_scale = float(1.0),
 	float3 mxp_normal = float3(::state::transform_normal(::state::coordinate_internal,::state::coordinate_world,::state::normal())),
-	float3 mxp_tangent = float3(state::transform_vector(::state::coordinate_internal,::state::coordinate_world,::state::texture_tangent_u(0)))
+	float3 mxp_tangent = float3(state::transform_vector(::state::coordinate_internal,::state::coordinate_world,::state::texture_tangent_u(0))),
+	float3 mxp_bitangent = float3(state::transform_vector(::state::coordinate_internal,::state::coordinate_world,::state::texture_tangent_v(0)))
 )
 	[[
 		anno::description("Node Group: math")
 	]]
 {
-	return mx_normalmap_vector2(mxp_in, mxp_space, float2(mxp_scale, mxp_scale), mxp_normal, mxp_tangent);
+	return mx_normalmap_vector2(mxp_in, float2(mxp_scale, mxp_scale), mxp_normal, mxp_tangent, mxp_bitangent);
 }
 
 export float3x3 mx_transpose_matrix33(

source/MaterialXRenderMsl/MslPipelineStateObject.mm

@@ -490,6 +490,13 @@ int GetStrideOfMetalType(MTLDataType type)
         bindAttribute(renderCmdEncoder, foundList, mesh);
     }
 
+    // Bind bitangents
+    findInputs(HW::IN_BITANGENT, attributeList, foundList, true);
+    if (foundList.size())
+    {
+        bindAttribute(renderCmdEncoder, foundList, mesh);
+    }
+
     // Bind colors
     // Search for anything that starts with the color prefix
     findInputs(HW::IN_COLOR + "_", attributeList, foundList, false);