Improved the slice rendering window: Added support for moving slice by clicking and dragging mouse. Added more descriptions. Added support for showing more than one slice rendering window.

Assets/Editor/SliceRenderingEditorWindow.cs

@@ -4,14 +4,26 @@ using UnityEditor;
 public class SliceRenderingEditorWindow : EditorWindow
 {
     private int selectedPlaneIndex = -1;
+    private bool handleMouseMovement = false;
+    private Vector2 prevMousePos;
 
     [MenuItem("Volume Rendering/Slice renderer")]
     static void ShowWindow()
     {
-        SliceRenderingEditorWindow wnd = (SliceRenderingEditorWindow)EditorWindow.GetWindow(typeof(SliceRenderingEditorWindow));
+        SliceRenderingEditorWindow wnd = new SliceRenderingEditorWindow();
         wnd.Show();
     }
 
+    private void OnFocus()
+    {
+        // set selected plane as active GameObject in Hierarchy
+        SlicingPlane[] spawnedPlanes = FindObjectsOfType<SlicingPlane>();
+        if (selectedPlaneIndex != -1 && spawnedPlanes.Length > 0)
+        {
+            Selection.activeGameObject = spawnedPlanes[selectedPlaneIndex].gameObject;
+        }
+    }
+
     private void OnGUI()
     {
         SlicingPlane[] spawnedPlanes = FindObjectsOfType<SlicingPlane>();
@@ -24,19 +36,49 @@ public class SliceRenderingEditorWindow : EditorWindow
         if(selectedPlaneIndex != -1 && spawnedPlanes.Length > 0)
         {
             SlicingPlane planeObj = spawnedPlanes[System.Math.Min(selectedPlaneIndex, spawnedPlanes.Length - 1)];
+            // Draw the slice view
             Material mat = planeObj.GetComponent<MeshRenderer>().sharedMaterial;
             Graphics.DrawTexture(bgRect, mat.GetTexture("_DataTex"), mat);
+
+            // Handle mouse click inside slice view (activates moving the plane with mouse)
+            if (Event.current.type == EventType.MouseDown && Event.current.button == 0 && bgRect.Contains(new Vector2(Event.current.mousePosition.x, Event.current.mousePosition.y)))
+            {
+                handleMouseMovement = true;
+                prevMousePos = Event.current.mousePosition;
+            }
+
+            // Handle mouse movement (move the plane)
+            if(handleMouseMovement)
+            {
+                Vector2 mouseOffset = (Event.current.mousePosition - prevMousePos) / new Vector2(bgRect.width, bgRect.height);
+                if(Mathf.Abs(mouseOffset.y) > 0.00001f)
+                {
+                    planeObj.transform.Translate(Vector3.up * mouseOffset.y);
+                    prevMousePos = Event.current.mousePosition;
+                }
+            }
         }
 
-        if(GUI.Button(new Rect(0.0f, bgRect.y + bgRect.height + 20.0f, 100.0f, 100.0f), "<"))
+        if(Event.current.type == EventType.MouseUp)
+            handleMouseMovement = false;
+
+        // Show buttons for changing the active plane
+        if(spawnedPlanes.Length > 0)
         {
-            selectedPlaneIndex = (selectedPlaneIndex - 1) % spawnedPlanes.Length;
+            if (GUI.Button(new Rect(0.0f, bgRect.y + bgRect.height + 20.0f, 100.0f, 30.0f), "previous\nplane"))
+            {
+                selectedPlaneIndex = (selectedPlaneIndex - 1) % spawnedPlanes.Length;
+                Selection.activeGameObject = spawnedPlanes[selectedPlaneIndex].gameObject;
+            }
+            if (GUI.Button(new Rect(120.0f, bgRect.y + bgRect.height + 20.0f, 100.0f, 30.0f), "next\nplane"))
+            {
+                selectedPlaneIndex = (selectedPlaneIndex + 1) % spawnedPlanes.Length;
+                Selection.activeGameObject = spawnedPlanes[selectedPlaneIndex].gameObject;
+            }
         }
-        if (GUI.Button(new Rect(120.0f, bgRect.y + bgRect.height + 20.0f, 100.0f, 100.0f), ">"))
-        {
-            selectedPlaneIndex = (selectedPlaneIndex + 1) % spawnedPlanes.Length;
-        }
-        if (GUI.Button(new Rect(240.0f, bgRect.y + bgRect.height + 20.0f, 100.0f, 100.0f), "+"))
+        
+        // Show button for adding new plane
+        if (GUI.Button(new Rect(240.0f, bgRect.y + bgRect.height + 20.0f, 100.0f, 30.0f), "add\nplane"))
         {
             VolumeRenderedObject volRend = FindObjectOfType<VolumeRenderedObject>();
             if(volRend != null)
@@ -45,6 +87,10 @@ public class SliceRenderingEditorWindow : EditorWindow
                 volRend.CreateSlicingPlane();
             }
         }
+
+        // Show hint
+        if (spawnedPlanes.Length > 0)
+            GUI.Label(new Rect(0.0f, bgRect.y + bgRect.height + 60.0f, 450.0f, 30.0f), "Move plane by left clicking in the above view and dragging the mouse,\n or simply move it in the object hierarchy.");
     }
 
     public void OnInspectorUpdate()