PreviewRenderUtilityExample

PreviewRenderUtilityExample.cs

using UnityEditor;
using UnityEngine;
using UnityLogging;

public class PreviewRenderUtilityExample : EditorWindow
{
    private GameObject _gameObject;
    private GameObject previewObject;

    [MenuItem("Window/PreviewRenderUtilityExample")]
    private static void CreateWindow()
    {
        var win = GetWindow<PreviewRenderUtilityExample>();
        win.Show();
    }

    private PreviewRenderUtility _previewRenderUtility;
    private Texture _outputTexture;

    private void OnEnable()
    {
        if (_previewRenderUtility != null)
            _previewRenderUtility.Cleanup();
        _previewRenderUtility = new PreviewRenderUtility(true);
        System.GC.SuppressFinalize(_previewRenderUtility);
        var camera = _previewRenderUtility.camera;
        camera.fieldOfView = 30f;
        camera.nearClipPlane = 0.3f;
        camera.farClipPlane = 1000;
        camera.transform.position = new Vector3(2.5f, 1f, -2.5f);
        camera.transform.LookAt(Vector3.zero);

        // var obj = GameObject.CreatePrimitive(PrimitiveType.Cube);
        // DestroyImmediate(obj);
    }

    private RenderTexture CreatePreviewTexture(GameObject obj)
    {
        if (obj == null)
        {
            return null;
        }

        _previewRenderUtility.BeginPreview(new Rect(0, 0, 128, 128), GUIStyle.none);

        _previewRenderUtility.lights[0].transform.localEulerAngles = new Vector3(30, 30, 0);
        _previewRenderUtility.lights[0].intensity = 2;
        _previewRenderUtility.AddSingleGO(obj);
        _previewRenderUtility.camera.Render();

        return (RenderTexture) _previewRenderUtility.EndPreview();
    }

    private void OnGUI()
    {
        GameObject oldGameObject = _gameObject;
        _gameObject = EditorGUILayout.ObjectField("Object", _gameObject, typeof(GameObject), true) as GameObject;
        if (oldGameObject != null && _gameObject != null && !_gameObject.Equals(oldGameObject))
        {
            oldGameObject = _gameObject;
            Logging.Log("Instantiate", "Preview");
            DestroyImmediate(previewObject);
            previewObject = Instantiate(oldGameObject);
        }

        if (_previewRenderUtility != null || _outputTexture != null)
        {
            // if (_gameObject!=null)
            {
                Logging.Log("start preview", "Preview");
                _outputTexture = CreatePreviewTexture(previewObject);
                // GUI.DrawTexture(new Rect(0,0, 300, 300), _outputTexture);
                GUILayout.Box(_outputTexture);
            }
        }
    }

    private void OnDisable()
    {
        _previewRenderUtility.Cleanup();
    }
}