How can I rotate cubemap in shadergraph?

Question

I know how to rotate cube map with legacy surface shader

Shader Rotation Matrix:

uniform float4x4 _Rotation;
          o.Emission = texCUBE (_Cube,  mul(_Rotation, float4(IN.worldRefl,0))).rgb;

RotateCubeMap:

using UnityEngine;

public class RotateCubeMap : MonoBehaviour
{
    public float speed = 20;
    private MeshRenderer _meshRenderer;

    private void Awake()
    {
        _meshRenderer = GetComponent<MeshRenderer>();
    }

    public void Update()
    {
        var rot = Quaternion.Euler (0, Time.time*speed, 0); 
        var m = new Matrix4x4 ();
        m.SetTRS(Vector3.zero, rot,new Vector3(1,1,1) );
        _meshRenderer.material.SetMatrix ("_Rotation", m);
    }
}

I tried to recreate it by shadergraph

but it didn't work!

I need a result like this:

Answer 1

I understood what is my problem!

It's because Instead of multiplying WorldReflect with Rotation Matrix

I multiplied the ObjectSpaceViewDirection with Rotation Matrix

so I could fix it by using custom function:

Custom function basic setup:

use this script inside the shader:

float3 WorldReflect = reflect(-ObjectSpaceViewDirection, ObjectSpaceNormal);
OutPut =  SAMPLE_TEXTURECUBE_LOD(_CubeMap, sampler_CubeMap, mul(Rotation, float4(WorldReflect,0)) , 0);

Answer 2

Possibly found a simpler way without a custom function.

Use the Rotate About Axis Node and just set the Axis you want to rotate around (vertical is Y) to 1 and others to 0.

Connect the ViewDirection Node to the In and the Out to the SampleCubeMap ViewDir.

Answer 3

I stumbled uppon this thread a bit late, but this could be of help to other people.

I recreated the rotation inside shadergraph. Heres the image:

Basically is just calculate reflection vector between view direction and normal vector, and then rotate about axis, in this case Y needs to be set to 1 and voila. Plug it into a Sample Cubemap.

Hope this helps!