Fixed planar/triplanar so that tangent space normal aren't flipped when facing away from the world axes.

Assets/ScriptableRenderLoop/HDRenderLoop/Material/Lit/LitSurfaceData.hlsl

     ADD_IDX(layerTexCoord.base).uv =    ADD_IDX(_UVMappingMask).x * input.texCoord0 +
                                         ADD_IDX(_UVMappingMask).y * input.texCoord1 + 
                                         ADD_IDX(_UVMappingMask).z * input.texCoord3 +
-                                        ADD_IDX(_UVMappingMask).w * position.xz;
+                                        ADD_IDX(_UVMappingMask).w * -position.xz;
-                        ADD_IDX(_UVMappingMask).w * position.xz;
+						ADD_IDX(_UVMappingMask).w * -position.xz;
 
     ADD_IDX(layerTexCoord.details).uv = TRANSFORM_TEX(uvDetails, ADD_IDX(_DetailMap));
 
-    ADD_IDX(layerTexCoord.base).uvYZ = position.zy;
-    ADD_IDX(layerTexCoord.base).uvZX = position.xz;
-    ADD_IDX(layerTexCoord.base).uvXY = float2(-position.x, position.y);
+	float3 direction = sign(input.tangentToWorld[2].xyz);
+
+	// In triplanar, if we are facing away from the world axis, a different axis will be flipped for each direction.
+	// This is particularly problematic for tangent space normal maps which need to be in the right direction.
+	// So we multiplying the offending coordinate by the sign of the normal.
+	ADD_IDX(layerTexCoord.base).uvYZ = float2(direction.x * position.z, position.y);
+    ADD_IDX(layerTexCoord.base).uvZX = -float2(position.x, direction.y * position.z);
+    ADD_IDX(layerTexCoord.base).uvXY = float2(-position.x, direction.z * position.y);
-    ADD_IDX(layerTexCoord.details).uvYZ = TRANSFORM_TEX(position.zy, ADD_IDX(_DetailMap));
-    ADD_IDX(layerTexCoord.details).uvZX = TRANSFORM_TEX(position.xz, ADD_IDX(_DetailMap));
-    ADD_IDX(layerTexCoord.details).uvXY = TRANSFORM_TEX(float2(-position.x, position.y), ADD_IDX(_DetailMap));
+	ADD_IDX(layerTexCoord.details).uvYZ = TRANSFORM_TEX(ADD_IDX(layerTexCoord.base).uvYZ, ADD_IDX(_DetailMap));
+	ADD_IDX(layerTexCoord.details).uvZX = TRANSFORM_TEX(ADD_IDX(layerTexCoord.base).uvZX, ADD_IDX(_DetailMap));
+	ADD_IDX(layerTexCoord.details).uvXY = TRANSFORM_TEX(ADD_IDX(layerTexCoord.base).uvXY, ADD_IDX(_DetailMap));
 }
 
 void ADD_IDX(ApplyDisplacement)(inout FragInput input, inout LayerTexCoord layerTexCoord)