[ShaderGraph] [2021.1/staging] [bugfix 1308156] Backport bugfix for view direction node in tangent space being not using the calculation (#3198)

Author: joshua-davis

com.unity.render-pipelines.high-definition/Editor/Material/ShaderGraph/Templates/SharedCode.template.hlsl

@@ -45,7 +45,7 @@ SurfaceDescriptionInputs FragInputsToSurfaceDescriptionInputs(FragInputs input,
     $SurfaceDescriptionInputs.ObjectSpaceViewDirection:  output.ObjectSpaceViewDirection =    TransformWorldToObjectDir(output.WorldSpaceViewDirection);
     $SurfaceDescriptionInputs.ViewSpaceViewDirection:    output.ViewSpaceViewDirection =      TransformWorldToViewDir(output.WorldSpaceViewDirection);
     $SurfaceDescriptionInputs.TangentSpaceViewDirection: float3x3 tangentSpaceTransform =     float3x3(output.WorldSpaceTangent,output.WorldSpaceBiTangent,output.WorldSpaceNormal);
-    $SurfaceDescriptionInputs.TangentSpaceViewDirection: output.TangentSpaceViewDirection =   mul(tangentSpaceTransform, output.WorldSpaceViewDirection);
+    $SurfaceDescriptionInputs.TangentSpaceViewDirection: output.TangentSpaceViewDirection =   length(output.WorldSpaceViewDirection) * TransformWorldToTangent(output.WorldSpaceViewDirection, tangentSpaceTransform);
     $SurfaceDescriptionInputs.WorldSpacePosition:        output.WorldSpacePosition =          input.positionRWS;
     $SurfaceDescriptionInputs.ObjectSpacePosition:       output.ObjectSpacePosition =         TransformWorldToObject(input.positionRWS);
     $SurfaceDescriptionInputs.ViewSpacePosition:         output.ViewSpacePosition =           TransformWorldToView(input.positionRWS);

com.unity.render-pipelines.high-definition/Editor/Material/ShaderGraph/Templates/VertexAnimation.template.hlsl

@@ -23,9 +23,9 @@ VertexDescriptionInputs AttributesMeshToVertexDescriptionInputs(AttributesMesh i
     $VertexDescriptionInputs.AbsoluteWorldSpacePosition:output.AbsoluteWorldSpacePosition =  GetAbsolutePositionWS(TransformObjectToWorld(input.positionOS));
     $VertexDescriptionInputs.WorldSpaceViewDirection:   output.WorldSpaceViewDirection =     GetWorldSpaceNormalizeViewDir(output.WorldSpacePosition);
     $VertexDescriptionInputs.ObjectSpaceViewDirection:  output.ObjectSpaceViewDirection =    TransformWorldToObjectDir(output.WorldSpaceViewDirection);
-    $VertexDescriptionInputs.ViewSpaceViewDirection:    output.ViewSpaceViewDirection =      TransformWorldToViewDir(output.WorldSpaceViewDirection);
+    $VertexDescriptionInputs.ViewSpaceViewDirection:    output.ViewSpaceViewDirection =      length(output.WorldSpaceViewDirection) * TransformWorldToViewDir(output.WorldSpaceViewDirection);
     $VertexDescriptionInputs.TangentSpaceViewDirection: float3x3 tangentSpaceTransform =     float3x3(output.WorldSpaceTangent,output.WorldSpaceBiTangent,output.WorldSpaceNormal);
-    $VertexDescriptionInputs.TangentSpaceViewDirection: output.TangentSpaceViewDirection =   mul(tangentSpaceTransform, output.WorldSpaceViewDirection);
+    $VertexDescriptionInputs.TangentSpaceViewDirection: output.TangentSpaceViewDirection =   TransformWorldToTangent(output.WorldSpaceViewDirection, tangentSpaceTransform);
     $VertexDescriptionInputs.ScreenPosition:            output.ScreenPosition =              ComputeScreenPos(TransformWorldToHClip(output.WorldSpacePosition), _ProjectionParams.x);
     $VertexDescriptionInputs.uv0:                       output.uv0 =                         input.uv0;
     $VertexDescriptionInputs.uv1:                       output.uv1 =                         input.uv1;

com.unity.shadergraph/CHANGELOG.md

@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Fixed an issue with the Gradient color picker displaying different values than the selected color.
 - Fixed an issue with inactive node deletion throwing a superfluous exception.
 - Fixed an issue on upgrading graphs with inactive Master Nodes causing null ref errors. [1298867](https://issuetracker.unity3d.com/product/unity/issues/guid/1298867/)
+- Fixed the ViewDirection Node in Tangent space's calculation to match how the transform node works.
 
 ## [10.3.0] - 2020-11-03
 

com.unity.shadergraph/Editor/Generation/Templates/BuildSurfaceDescriptionInputs.template.hlsl

@@ -32,7 +32,7 @@ SurfaceDescriptionInputs BuildSurfaceDescriptionInputs(Varyings input)
     $SurfaceDescriptionInputs.ObjectSpaceViewDirection:  output.ObjectSpaceViewDirection =    TransformWorldToObjectDir(output.WorldSpaceViewDirection);
     $SurfaceDescriptionInputs.ViewSpaceViewDirection:    output.ViewSpaceViewDirection =      TransformWorldToViewDir(output.WorldSpaceViewDirection);
     $SurfaceDescriptionInputs.TangentSpaceViewDirection: float3x3 tangentSpaceTransform =     float3x3(output.WorldSpaceTangent,output.WorldSpaceBiTangent,output.WorldSpaceNormal);
-    $SurfaceDescriptionInputs.TangentSpaceViewDirection: output.TangentSpaceViewDirection =   mul(tangentSpaceTransform, output.WorldSpaceViewDirection);
+    $SurfaceDescriptionInputs.TangentSpaceViewDirection: output.TangentSpaceViewDirection =   length(output.WorldSpaceViewDirection) * TransformWorldToTangent(output.WorldSpaceViewDirection, tangentSpaceTransform);
     $SurfaceDescriptionInputs.WorldSpacePosition:        output.WorldSpacePosition =          input.positionWS;
     $SurfaceDescriptionInputs.ObjectSpacePosition:       output.ObjectSpacePosition =         TransformWorldToObject(input.positionWS);
     $SurfaceDescriptionInputs.ViewSpacePosition:         output.ViewSpacePosition =           TransformWorldToView(input.positionWS);

com.unity.shadergraph/Editor/Generation/Templates/BuildVertexDescriptionInputs.template.hlsl

@@ -22,9 +22,9 @@ VertexDescriptionInputs BuildVertexDescriptionInputs(Attributes input)
     $VertexDescriptionInputs.AbsoluteWorldSpacePosition:output.AbsoluteWorldSpacePosition =  GetAbsolutePositionWS(TransformObjectToWorld(input.positionOS));
     $VertexDescriptionInputs.WorldSpaceViewDirection:   output.WorldSpaceViewDirection =     GetWorldSpaceNormalizeViewDir(output.WorldSpacePosition);
     $VertexDescriptionInputs.ObjectSpaceViewDirection:  output.ObjectSpaceViewDirection =    TransformWorldToObjectDir(output.WorldSpaceViewDirection);
-    $VertexDescriptionInputs.ViewSpaceViewDirection:    output.ViewSpaceViewDirection =      TransformWorldToViewDir(output.WorldSpaceViewDirection);
+    $VertexDescriptionInputs.ViewSpaceViewDirection:    output.ViewSpaceViewDirection =      length(output.WorldSpaceViewDirection) * TransformWorldToViewDir(output.WorldSpaceViewDirection);
     $VertexDescriptionInputs.TangentSpaceViewDirection: float3x3 tangentSpaceTransform =     float3x3(output.WorldSpaceTangent,output.WorldSpaceBiTangent,output.WorldSpaceNormal);
-    $VertexDescriptionInputs.TangentSpaceViewDirection: output.TangentSpaceViewDirection =   mul(tangentSpaceTransform, output.WorldSpaceViewDirection);
+    $VertexDescriptionInputs.TangentSpaceViewDirection: output.TangentSpaceViewDirection =   TransformWorldToTangent(output.WorldSpaceViewDirection, tangentSpaceTransform);
     $VertexDescriptionInputs.ScreenPosition:            output.ScreenPosition =              ComputeScreenPos(TransformWorldToHClip(output.WorldSpacePosition), _ProjectionParams.x);
     $VertexDescriptionInputs.uv0:                       output.uv0 =                         input.uv0;
     $VertexDescriptionInputs.uv1:                       output.uv1 =                         input.uv1;