Reflection shading now working. Added example with distortion.

Code/PlanarReflection.cs

-using System.Collections;
-using System.Collections.Generic;
-using UnityEngine.Rendering;
-using UnityEngine.Rendering.LWRP;
+using UnityEngine.Rendering;
 using UnityEngine;
 
-
 public class PlanarReflection : MonoBehaviour
 {
   public Vector3 planeNormal;
@@ -16,71 +12,46 @@ public class PlanarReflection : MonoBehaviour
   Camera reflectionCamera;
   Vector3 reflectionScale;
   RenderTexture reflectionTexture;
+  Vector4 reflectionPlane;
 
+  //-----------------------------------------------------------------------------
   void Start()
   {
     reflectionTexture = new RenderTexture(Screen.width, Screen.height, 24);
     reflectionMaterial.SetTexture("_PlanarReflectionTexture", reflectionTexture);
-    // reflectionCamera = gameObject.AddComponent<Camera>();
     reflectionCamera = GetComponent<Camera>();
     RenderPipelineManager.beginCameraRendering += OnBeginRendering;
+    reflectionPlane = new Vector4(planeNormal.x, planeNormal.y, planeNormal.z, -Vector3.Dot(pointOnPlane, planeNormal.normalized));
   }
 
+  //-----------------------------------------------------------------------------
   void OnBeginRendering(ScriptableRenderContext context, Camera camera)
   {
     if (camera.tag == "MainCamera")
     {
       reflectionCamera.CopyFrom(camera);
+      reflectionCamera.clearFlags = CameraClearFlags.SolidColor;
+      reflectionCamera.backgroundColor = Color.black;
       reflectionCamera.depth -= 1;
       reflectionCamera.targetTexture = reflectionTexture;
       reflectionCamera.cullingMask = reflectionLayers;
 
       Vector3 cameraForwardWorld = camera.transform.forward;
-      Vector3 cameraUpWorld = camera.transform.up;
       Vector3 cameraPosWorld = camera.transform.position;
 
+      // temp - remove this
+      reflectionPlane = new Vector4(planeNormal.x, planeNormal.y, planeNormal.z, -Vector3.Dot(pointOnPlane, planeNormal.normalized));
 
       Matrix4x4 refMat = Matrix4x4.identity;
-      CalculateReflectionMatrix(ref refMat, planeNormal);
+      CalculateReflectionMatrix(ref refMat, reflectionPlane);
 
-      reflectionCamera.transform.position = refMat * cameraPosWorld;
+      reflectionCamera.transform.position = refMat * new Vector4(cameraPosWorld.x, cameraPosWorld.y, cameraPosWorld.z, 1.0f);
       reflectionCamera.transform.forward = refMat * cameraForwardWorld;
       reflectionMaterial.SetTexture("_PlanarReflectionTexture", reflectionTexture);
-
-
-      // Vector3 test = reflection * cameraForwardWorld;
-      // Debug.Log("from " + cameraForwardWorld + " -to- " + test);
-      // Matrix4x4 planeReflection = reflectionPlaneObject.transform.worldToLocalMatrix;
-      // planeReflection.m30 = 0f;
-      // planeReflection.m31 = 0f;
-      // planeReflection.m32 = 0f;
-      // planeReflection.m33 = 1f;
-
-      // var test = planeReflection * reflection;
-      // var test3 = reflection * planeReflection;
-      // var test2 = test * Vector3.up;
-      // Debug.Log(test3);
-      // Debug.Log(test);
-      // planeReflection = planeReflection * reflection;
-
-      // Vector3 cameraForwardPlane = reflectionPlaneObject.InverseTransformDirection(cameraForwardWorld);
-      // Vector3 cameraUpPlane = reflectionPlaneObject.InverseTransformDirection(cameraUpWorld);
-      // Vector3 cameraPosPlane = reflectionPlaneObject.InverseTransformPoint(cameraPosWorld);
-
-      // cameraForwardPlane = planeReflection * cameraForwardPlane;
-      // cameraUpPlane = planeReflection * cameraUpPlane;
-      // cameraPosPlane = planeReflection * cameraPosPlane;
-
-      // cameraForwardWorld = reflectionPlaneObject.TransformDirection(cameraForwardPlane);
-      // cameraUpWorld = reflectionPlaneObject.TransformDirection(cameraUpPlane);
-      // cameraPosWorld = reflectionPlaneObject.TransformPoint(cameraPosPlane);
-
-      // reflectionCamera.transform.position = cameraPosWorld;
-      // reflectionCamera.transform.LookAt(cameraPosWorld + cameraForwardWorld, cameraUpWorld);
     }
-
   }
 
+  //-----------------------------------------------------------------------------
   private static void CalculateReflectionMatrix(ref Matrix4x4 reflectionMat, Vector4 plane)
   {
     reflectionMat.m00 = (1F - 2F * plane[0] * plane[0]);

ShaderGraphs/Demo/[Demo] Planar Reflection Distortion.shadergraph.meta

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ShaderGraphs/Misc/Normalized Device Coordinate.shadersubgraph.meta

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