WeirdPerspectiveThing

using UnityEngine;
using System.Collections;

[ExecuteInEditMode]
public class TreesCamera : MonoBehaviour {
	private void OnEnable(){
		Camera.onPreRender += PreRender;
		Camera.onPostRender += PostRender;
	}

	private void OnDisable(){
		Camera.onPreRender -= PreRender;
		Camera.onPostRender -= PostRender;
	}

	private void Start(){
		GetComponent<Camera>().transparencySortMode = TransparencySortMode.Orthographic;
	}

	private static Matrix4x4 flipZ = Matrix4x4.Scale(new Vector3(1, 1, -1));
	private void PreRender(Camera cam){
		var transform = cam.transform;
		var m = Matrix4x4.identity;
		m.SetColumn(2, -transform.up);

		cam.worldToCameraMatrix = flipZ*transform.worldToLocalMatrix*m;
	}

	private void PostRender(Camera cam){
		if(cam.cameraType == CameraType.SceneView) cam.ResetWorldToCameraMatrix();
	}
}