Fix review comments:

* Put all variables in cbuffer.
* Delete motion vector pass.
* Follow naming convention for basemap gen shader.

com.unity.render-pipelines.high-definition/HDRP/Material/TerrainLit/TerrainLit.shader

     // variable declaration
     //-------------------------------------------------------------------------------------
 
-    #include "../../Material/Lit/LitProperties.hlsl"
-
     // All our shaders use same name for entry point
     #pragma vertex Vert
     #pragma fragment Frag
             #include "TerrainLitSharePass.hlsl"
             #include "TerrainLitData.hlsl"
             #include "../../ShaderPass/ShaderPassLightTransport.hlsl"
-
-            ENDHLSL
-        }
-
-        Pass
-        {
-            Name "Motion Vectors"
-            Tags{ "LightMode" = "MotionVectors" } // Caution, this need to be call like this to setup the correct parameters by C++ (legacy Unity)
-
-            // If velocity pass (motion vectors) is enabled we tag the stencil so it don't perform CameraMotionVelocity
-            Stencil
-            {
-                WriteMask [_StencilWriteMaskMV]
-                Ref [_StencilRefMV]
-                Comp Always
-                Pass Replace
-            }
-
-            Cull[_CullMode]
-
-            ZWrite On
-
-            HLSLPROGRAM
-
-            #define SHADERPASS SHADERPASS_VELOCITY
-            #include "../../ShaderVariables.hlsl"
-            #include "../../Material/Material.hlsl"
-            #include "../Lit/ShaderPass/LitVelocityPass.hlsl"
-            #include "TerrainLitData.hlsl"
-            #include "../../ShaderPass/ShaderPassVelocity.hlsl"
 
             ENDHLSL
         }

com.unity.render-pipelines.high-definition/HDRP/Material/TerrainLit/TerrainLitData.hlsl

 
 #include "CoreRP/ShaderLibrary/Sampling/SampleUVMapping.hlsl"
 #include "../MaterialUtilities.hlsl"
+
+// We don't use emission for terrain
+#define _EmissiveColor float3(0,0,0)
+#define _AlbedoAffectEmissive 0
-#include "../Decal/DecalUtilities.hlsl"
+#undef _EmissiveColor
+#undef _AlbedoAffectEmissive
+#include "../Decal/DecalUtilities.hlsl"
-#include "TerrainLitDataMeshModification.hlsl"
 
 void GetSurfaceAndBuiltinData(inout FragInputs input, float3 V, inout PositionInputs posInput, out SurfaceData surfaceData, out BuiltinData builtinData)
 {

com.unity.render-pipelines.high-definition/HDRP/Material/TerrainLit/TerrainLitDataMeshModification.hlsl

-#ifdef UNITY_INSTANCING_ENABLED
-    TEXTURE2D(_TerrainHeightmapTexture);
-    TEXTURE2D(_TerrainNormalmapTexture);
-    float4 _TerrainHeightmapRecipSize;   // float4(1.0f/width, 1.0f/height, 1.0f/(width-1), 1.0f/(height-1))
-    float4 _TerrainHeightmapScale;       // float4(hmScale.x, hmScale.y / (float)(kMaxHeight), hmScale.z, 0.0f)
-#endif
-
-#define API_HAS_GURANTEED_R16_SUPPORT 0 //!(SHADER_API_VULKAN)
-#if (API_HAS_GURANTEED_R16_SUPPORT)
-    return height.r;
-#else
+    // 16-bit height value is packed into two 8-bit channels.
-#endif
 }
 
 UNITY_INSTANCING_BUFFER_START(Terrain)

com.unity.render-pipelines.high-definition/HDRP/Material/TerrainLit/TerrainLitData_Basemap.hlsl

 
 #include "CoreRP/ShaderLibrary/Sampling/SampleUVMapping.hlsl"
 #include "../MaterialUtilities.hlsl"
-#include "../Lit/LitBuiltinData.hlsl"
-#include "../Decal/DecalUtilities.hlsl"
-TEXTURE2D(_MainTex);
-TEXTURE2D(_MetallicTex);
-SAMPLER(sampler_MainTex);
+// We don't use emission for terrain
+#define _EmissiveColor float3(0,0,0)
+#define _AlbedoAffectEmissive 0
+#include "../Lit/LitBuiltinData.hlsl"
+#undef _EmissiveColor
+#undef _AlbedoAffectEmissive
-#include "TerrainLitDataMeshModification.hlsl"
+#include "../Decal/DecalUtilities.hlsl"
+#include "TerrainLitSplatCommon.hlsl"
 
 void GetSurfaceAndBuiltinData(FragInputs input, float3 V, inout PositionInputs posInput, out SurfaceData surfaceData, out BuiltinData builtinData)
 {

com.unity.render-pipelines.high-definition/HDRP/Material/TerrainLit/TerrainLitSplatCommon.hlsl

     #define _LAYER_COUNT 4
 #endif
 
-#define DECLARE_TERRAIN_LAYER(n)    \
-    TEXTURE2D(_Splat##n);           \
-    TEXTURE2D(_Normal##n);          \
-    TEXTURE2D(_Mask##n);            \
-    float4 _Splat##n##_ST;          \
-    float _Metallic##n;             \
-    float _Smoothness##n;           \
-    float _NormalScale##n;          \
-    float4 _DiffuseRemapScale##n;   \
-    float4 _MaskMapRemapOffset##n;  \
-    float4 _MaskMapRemapScale##n
+#define DECLARE_TERRAIN_LAYER_TEXS(n)   \
+    TEXTURE2D(_Splat##n);               \
+    TEXTURE2D(_Normal##n);              \
+    TEXTURE2D(_Mask##n)
+
+DECLARE_TERRAIN_LAYER_TEXS(0);
+DECLARE_TERRAIN_LAYER_TEXS(1);
+DECLARE_TERRAIN_LAYER_TEXS(2);
+DECLARE_TERRAIN_LAYER_TEXS(3);
+#ifdef _TERRAIN_8_LAYERS
+    DECLARE_TERRAIN_LAYER_TEXS(4);
+    DECLARE_TERRAIN_LAYER_TEXS(5);
+    DECLARE_TERRAIN_LAYER_TEXS(6);
+    DECLARE_TERRAIN_LAYER_TEXS(7);
+    TEXTURE2D(_Control1);
+#endif
-DECLARE_TERRAIN_LAYER(0);
-DECLARE_TERRAIN_LAYER(1);
-DECLARE_TERRAIN_LAYER(2);
-DECLARE_TERRAIN_LAYER(3);
+#undef DECLARE_TERRAIN_LAYER_TEXS
+TEXTURE2D(_MainTex);
+TEXTURE2D(_MetallicTex);
+SAMPLER(sampler_MainTex);
-#ifdef _TERRAIN_8_LAYERS
-    DECLARE_TERRAIN_LAYER(4);
-    DECLARE_TERRAIN_LAYER(5);
-    DECLARE_TERRAIN_LAYER(6);
-    DECLARE_TERRAIN_LAYER(7);
-    TEXTURE2D(_Control1);
+#ifdef UNITY_INSTANCING_ENABLED
+TEXTURE2D(_TerrainHeightmapTexture);
+TEXTURE2D(_TerrainNormalmapTexture);
-#undef DECLARE_TERRAIN_LAYER
+#define DECLARE_TERRAIN_LAYER_PROPS(n)  \
+    float4 _Splat##n##_ST;              \
+    float _Metallic##n;                 \
+    float _Smoothness##n;               \
+    float _NormalScale##n;              \
+    float4 _DiffuseRemapScale##n;       \
+    float4 _MaskMapRemapOffset##n;      \
+    float4 _MaskMapRemapScale##n
-float _HeightTransition;
+CBUFFER_START(UnityPerMaterial)
+
+    DECLARE_TERRAIN_LAYER_PROPS(0);
+    DECLARE_TERRAIN_LAYER_PROPS(1);
+    DECLARE_TERRAIN_LAYER_PROPS(2);
+    DECLARE_TERRAIN_LAYER_PROPS(3);
+    #ifdef _TERRAIN_8_LAYERS
+        DECLARE_TERRAIN_LAYER_PROPS(4);
+        DECLARE_TERRAIN_LAYER_PROPS(5);
+        DECLARE_TERRAIN_LAYER_PROPS(6);
+        DECLARE_TERRAIN_LAYER_PROPS(7);
+    #endif
+
+    float _HeightTransition;
+
+    #ifdef UNITY_INSTANCING_ENABLED
+        float4 _TerrainHeightmapRecipSize;   // float4(1.0f/width, 1.0f/height, 1.0f/(width-1), 1.0f/(height-1))
+        float4 _TerrainHeightmapScale;       // float4(hmScale.x, hmScale.y / (float)(kMaxHeight), hmScale.z, 0.0f)
+    #endif
+
+CBUFFER_END
+
+#undef DECLARE_TERRAIN_LAYER_PROPS
+
+#ifdef HAVE_VERTEX_MODIFICATION
+#include "TerrainLitDataMeshModification.hlsl"
+#endif
 
 float GetSumHeight(float4 heights0, float4 heights1)
 {

com.unity.render-pipelines.high-definition/HDRP/Material/TerrainLit/TerrainLit_Basemap.shader

     // variable declaration
     //-------------------------------------------------------------------------------------
 
-    #include "../../Material/Lit/LitProperties.hlsl"
-
     // All our shaders use same name for entry point
     #pragma vertex Vert
     #pragma fragment Frag
             #include "TerrainLitSharePass.hlsl"
             #include "TerrainLitData_Basemap.hlsl"
             #include "../../ShaderPass/ShaderPassLightTransport.hlsl"
-
-            ENDHLSL
-        }
-
-        Pass
-        {
-            Name "Motion Vectors"
-            Tags{ "LightMode" = "MotionVectors" } // Caution, this need to be call like this to setup the correct parameters by C++ (legacy Unity)
-
-            // If velocity pass (motion vectors) is enabled we tag the stencil so it don't perform CameraMotionVelocity
-            Stencil
-            {
-                WriteMask [_StencilWriteMaskMV]
-                Ref [_StencilRefMV]
-                Comp Always
-                Pass Replace
-            }
-
-            Cull[_CullMode]
-
-            ZWrite On
-
-            HLSLPROGRAM
-
-            #define SHADERPASS SHADERPASS_VELOCITY
-            #include "../../ShaderVariables.hlsl"
-            #include "../../Material/Material.hlsl"
-            #include "../Lit/ShaderPass/LitVelocityPass.hlsl"
-            #include "TerrainLitData_Basemap.hlsl"
-            #include "../../ShaderPass/ShaderPassVelocity.hlsl"
 
             ENDHLSL
         }

com.unity.render-pipelines.high-definition/HDRP/Material/TerrainLit/TerrainLit_Basemap_Gen.shader

         #endif
         #include "TerrainLitSplatCommon.hlsl"
 
-        struct appdata_t {
+        struct Attributes {
-        struct v2f
+        struct Varyings
-            float4 vertex : SV_POSITION;
+            float4 positionCS : SV_POSITION;
             float2 texcoord : TEXCOORD0;
         };
 
 
             HLSLPROGRAM
 
-            #pragma vertex vert
-            #pragma fragment frag
+            #pragma vertex Vert
+            #pragma fragment Frag
-            v2f vert(appdata_t v)
+            Varyings Vert(Attributes input)
-                v2f o;
-                o.vertex = TransformWorldToHClip(v.vertex);
-                o.texcoord = v.texcoord;
-                return o;
+                Varyings output;
+                output.positionCS = TransformWorldToHClip(input.vertex);
+                output.texcoord = input.texcoord;
+                return output;
-            float4 frag(v2f i) : SV_Target
+            float4 Frag(Varyings input) : SV_Target
-                TerrainSplatBlend(i.texcoord, float3(0, 0, 0), float3(0, 0, 0),
+                TerrainSplatBlend(input.texcoord, float3(0, 0, 0), float3(0, 0, 0),
                     albedo.xyz, normalTS, albedo.w, metallic, ao);
 
                 return albedo;
 
             HLSLPROGRAM
 
-            #pragma vertex vert
-            #pragma fragment frag
+            #pragma vertex Vert
+            #pragma fragment Frag
-            v2f vert(appdata_t v)
+            Varyings Vert(Attributes input)
-                v2f o;
-                o.vertex = TransformWorldToHClip(v.vertex);
-                o.texcoord = v.texcoord;
-                return o;
+                Varyings output;
+                output.positionCS = TransformWorldToHClip(input.vertex);
+                output.texcoord = input.texcoord;
+                return output;
-            float2 frag(v2f i) : SV_Target
+            float2 Frag(Varyings input) : SV_Target
-                TerrainSplatBlend(i.texcoord, float3(0, 0, 0), float3(0, 0, 0),
+                TerrainSplatBlend(input.texcoord, float3(0, 0, 0), float3(0, 0, 0),
                     albedo.xyz, normalTS, albedo.w, metallic, ao);
 
                 return float2(metallic, ao);

com.unity.render-pipelines.lightweight/LWRP/ShaderLibrary/Terrain/LightweightPassLitTerrain.hlsl

     float4 _TerrainHeightmapScale;       // float4(hmScale.x, hmScale.y / (float)(kMaxHeight), hmScale.z, 0.0f)
 #endif
 
-#define API_HAS_GURANTEED_R16_SUPPORT 0 //!(SHADER_API_VULKAN)
-#if (API_HAS_GURANTEED_R16_SUPPORT)
-    return height.r;
-#else
+    // 16-bit height value is packed into two 8-bit channels.
-#endif
 }
 
 UNITY_INSTANCING_BUFFER_START(Terrain)