Cleaned up MaterialGraphPreviewGenerator

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/MaterialGraphPreviewGenerator.cs

         private Light Light0 { get; set; }
         private Light Light1 { get; set; }
 
-        //private SavedRenderTargetState m_SavedState;
-
-
-        public Light[] Lights
-        {
-            get
-            {
-                return new[] {Light0, Light1};
-            }
-        }
 
         private static readonly Mesh[] s_Meshes = {null, null, null, null, null};
         private static Mesh s_PlaneMesh;
             Light1.color = new Color(.4f, .4f, .45f, 0f) * .7f;
 
             m_CheckerboardMaterial = new Material(Shader.Find("Hidden/Checkerboard"));
-            m_CheckerboardMaterial.SetFloat("_X", 8);
-            m_CheckerboardMaterial.SetFloat("_Y", 8);
 
             if (s_Meshes[0] == null)
             {
             }
         }
 
-        public float GetScaleFactor(float width, float height)
-        {
-            float scaleFacX = Mathf.Max(Mathf.Min(width * 2, 1024), width) / width;
-            float scaleFacY = Mathf.Max(Mathf.Min(height * 2, 1024), height) / height;
-            float result = Mathf.Min(scaleFacX, scaleFacY) * EditorGUIUtility.pixelsPerPoint;
-            //if (m_PixelPerfect)  //m_PixelPerfect = false; in PreviewRenderUtility default constructor.
-            //    result = Mathf.Max(Mathf.Round(result), 1f);
-            return result;
-        }
-
-            
-
-            //utility.BeginPreview(size, GUIStyle.none);
-
-            float scaleFac = GetScaleFactor(size.width, size.height);
-
-            int rtWidth = (int)(size.width * scaleFac);
-            int rtHeight = (int)(size.height * scaleFac);
+            int rtWidth = (int)(size.width);
+            int rtHeight = (int)(size.height);
 
             if (!m_RenderTexture || m_RenderTexture.width != rtWidth || m_RenderTexture.height != rtHeight)
             {
                 m_RenderTexture.hideFlags = HideFlags.HideAndDontSave;
 
                 m_Camera.targetTexture = m_RenderTexture;
-
-                foreach (var light in Lights) //redundant?
-                    light.enabled = true;
-            Graphics.Blit(null, m_RenderTexture, m_CheckerboardMaterial);
-            
-            //m_SavedState = new SavedRenderTargetState();
-            //EditorGUIUtility.SetRenderTextureNoViewport(m_RenderTexture);
-            GL.LoadOrtho();
-            //GL.LoadPixelMatrix(0, m_RenderTexture.width, m_RenderTexture.height, 0);
-            //ShaderUtil.rawViewportRect = new Rect(0, 0, m_RenderTexture.width, m_RenderTexture.height);
-            //ShaderUtil.rawScissorRect = new Rect(0, 0, m_RenderTexture.width, m_RenderTexture.height);
-            //GL.Clear(true, true, m_Camera.backgroundColor);
-
-            foreach (var light in Lights)
-                light.enabled = true;
-
+
+            //Debug.Log(string.Format("RT: {0}, Material: {1}", m_RenderTexture, m_CheckerboardMaterial));
+            
+            m_CheckerboardMaterial.SetFloat("_X", 32);
+            m_CheckerboardMaterial.SetFloat("_Y", 32);
+            Graphics.Blit(Texture2D.whiteTexture, m_RenderTexture, m_CheckerboardMaterial);
             
             if (mode == PreviewMode.Preview3D)
             {
             }
 
             EditorUtility.SetCameraAnimateMaterialsTime(m_Camera, time);
-            Lights[0].intensity = 1.0f;
-            Lights[0].transform.rotation = Quaternion.Euler(50f, 50f, 0);
-            Lights[1].intensity = 1.0f;
+            Light0.enabled = true;
+            Light0.intensity = 1.0f;
+            Light0.transform.rotation = Quaternion.Euler(50f, 50f, 0);
+            Light1.enabled = true;
+            Light1.intensity = 1.0f;
             m_Camera.clearFlags = CameraClearFlags.Depth;
 
             DrawMesh(
                 mat,
                 0);
-            Render(true, false);
+            m_Camera.Render();
-            return EndPreview();
+            Light0.enabled = false;
+            Light1.enabled = false;
+            return m_RenderTexture;
-            //EditorSceneManager.ClosePreviewScene(m_Scene); //Removing this line makes it work in the shader graph viewer (checkerboard disappears after windows loses and regains focus)
-
-            /*foreach (var go in m_GameObjects)
-                Object.DestroyImmediate(go);
-
-            m_GameObjects.Clear();*/
-        }
-
-        public void Reset() {
-            if (m_RenderTexture)
+            if (m_RenderTexture == null)
-            /*if (m_InvisibleMaterial != null)
+            if (Light0 == null) 
-                UnityEngine.Object.DestroyImmediate(m_InvisibleMaterial);
-                m_InvisibleMaterial = null;
-            }*/
+                UnityEngine.Object.DestroyImmediate(Light0.gameObject);
+                Light0 = null;
+            }
-            Dispose();
-        }
+            if (Light1 == null) 
+            {
+                UnityEngine.Object.DestroyImmediate(Light1.gameObject);
+                Light1 = null;
+            }
-        public Texture EndPreview()
-        {
-            //Unsupported.RestoreOverrideRenderSettings();
+            if (m_Camera == null) 
+            {
+                UnityEngine.Object.DestroyImmediate(m_Camera.gameObject);
+                m_Camera = null;
+            }
-            //m_SavedState.Restore();
-            FinishFrame();
-            return m_RenderTexture;
-        }
+            if (m_CheckerboardMaterial == null) 
+            {
+                UnityEngine.Object.DestroyImmediate(m_CheckerboardMaterial);
+                m_CheckerboardMaterial = null;
+            }
-        private void FinishFrame()
-        {
-            foreach (var light in Lights)
-                light.enabled = false;
+            EditorSceneManager.ClosePreviewScene(m_Scene);
-        public void DrawMesh(Mesh mesh, Vector3 pos, Quaternion rot, Material mat, int subMeshIndex)
+        private void DrawMesh(Mesh mesh, Vector3 pos, Quaternion rot, Material mat, int subMeshIndex)
-        public void DrawMesh(Mesh mesh, Vector3 pos, Quaternion rot, Material mat, int subMeshIndex, MaterialPropertyBlock customProperties, Transform probeAnchor, bool useLightProbe)
+        private void DrawMesh(Mesh mesh, Vector3 pos, Quaternion rot, Material mat, int subMeshIndex, MaterialPropertyBlock customProperties, Transform probeAnchor, bool useLightProbe)
-        }
-
-        public void Render(bool allowScriptableRenderPipeline = false, bool updatefov = true)
-        {
-            foreach (var light in Lights)
-                light.enabled = true;
-
-            //var oldAllowPipes = Unsupported.useScriptableRenderPipeline;
-            //Unsupported.useScriptableRenderPipeline = allowScriptableRenderPipeline;
-
-            float saveFieldOfView = m_Camera.fieldOfView;
-
-            if (updatefov)
-            {
-                // Calculate a view multiplier to avoid clipping when the preview width is smaller than the height.
-                float viewMultiplier = (m_RenderTexture.width <= 0 ? 1.0f : Mathf.Max(1.0f, (float)m_RenderTexture.height / m_RenderTexture.width));
-                // Multiply the viewing area by the viewMultiplier - it requires some conversions since the camera view is expressed as an angle.
-                m_Camera.fieldOfView = Mathf.Atan(viewMultiplier * Mathf.Tan(m_Camera.fieldOfView * 0.5f * Mathf.Deg2Rad)) * Mathf.Rad2Deg * 2.0f;
-            }
-
-            m_Camera.Render();
-
-            m_Camera.fieldOfView = saveFieldOfView;
-            //Unsupported.useScriptableRenderPipeline = oldAllowPipes;
         }
     }
 }

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/Presenters/NodePreviewPresenter.cs

                 bool status = false;
                 if (m_modificationScope >= ModificationScope.Graph)
                 {
-                    previewGenerator.Reset();
-
                     // TODO: Handle shader regeneration error
                     status = UpdatePreviewShader();
                 }
 
             return m_texture;
         }
+        void OnDisable()
+        {
+            if (m_PreviewGenerator != null)
+                m_PreviewGenerator.Dispose();
+        }
+
 
         protected virtual string GetPreviewShaderString()
         {

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Resources/Shaders/Checkerboard.shader

 
 			uniform float _X;
 			uniform float _Y;
+			
+			static const float4 col1 = float4(0.25, 0.25, 0.25, 1.0);
+			static const float4 col2 = float4(0.75, 0.75, 0.75, 1.0);
-				//float2 size = float2(16, 16);//textureSize2D(Texture0,0);
-				float4 col1 = float4(0.0, 0.0, 0.0, 1.0);
-				float4 col2 = float4(1.0, 1.0, 1.0, 1.0);
-				fixed4 col = (isEven) ? col1 : col2;
-				return col;//fixed4(1.0, 0.0, 0.0, 1.0);
+				return isEven ? col1 : col2;
 			}
 			ENDCG
 		}