Set consistent tessellation levels for camera and shadow views

Assets/ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/LitTessellation.hlsl

     bool frustumCulled = WorldViewFrustumCull(p0, p1, p2, maxDisplacement, (float4[4])unity_CameraWorldClipPlanes);
 
     bool faceCull = false;
+
+    // We use the position of the primary (scene view) camera in order
+    // to have identical tessellation levels for both the scene view and
+    // shadow views. Otherwise, depth comparisons become meaningless!
+    float3 camPosWS = _WorldSpaceCameraPos;
+
-        faceCull = BackFaceCullTriangle(p0, p1, p2, _TessellationBackFaceCullEpsilon, GetCurrentCameraPosition());
+        faceCull = BackFaceCullTriangle(p0, p1, p2, _TessellationBackFaceCullEpsilon, camPosWS);
     }
 #endif
 
     // Distance based tessellation
     if (_TessellationFactorMaxDistance > 0.0)
     {
-        float3 distFactor = GetDistanceBasedTessFactor(p0, p1, p2, GetCurrentCameraPosition(), _TessellationFactorMinDistance, _TessellationFactorMaxDistance);
+        float3 distFactor = GetDistanceBasedTessFactor(p0, p1, p2, camPosWS, _TessellationFactorMinDistance, _TessellationFactorMaxDistance);
         // We square the disance factor as it allow a better percptual descrease of vertex density.
         tessFactor *= distFactor * distFactor;
     }
 #else
         float2(0.0, 0.0),
 #endif
-        input.positionWS, 
+        input.positionWS,
         input.normalWS,
         layerTexCoord);
 

Assets/ScriptableRenderPipeline/HDRenderPipeline/ShaderVariables.hlsl

 #if SHADERPASS != SHADERPASS_DEPTH_ONLY
     return _WorldSpaceCameraPos;
 #else
-    // TEMP: this is a workaround until the shadow map pass sets '_WorldSpaceCameraPos'.
-    // This code is far more expensive than loading a constant from a cbuffer!
+    // TEMP: this is rather expensive. Then again, we need '_WorldSpaceCameraPos'
+    // to represent the position of the primary (scene view) camera in order to
+    // have identical tessellation levels for both the scene view and shadow views.
+    // Otherwise, depth comparisons become meaningless!
     float4x4 viewMat   = transpose(GetWorldToViewMatrix());
     float3   rotCamPos = viewMat[3].xyz;
    return mul((float3x3)viewMat, -rotCamPos);