866112: UG updated for annotation rotation

Author: sandhiyanatesh

ej2-asp-core-mvc/diagram/images/page_rotationreference.gif

@@ -650,4 +650,25 @@ You can add any number of annotations to a node or connector.
 
 ## Constraints
 
-The constraints property of annotation allows to enable or disable certain annotation behaviours. For instance, you can disable annotation editing.
+The constraints property of annotation allows to enable or disable certain annotation behaviours. For instance, you can disable annotation editing.
+
+## Annotation rotation
+
+The [`rotationReference`] property of an annotation allows you to control whether the text should rotate relative to its parent node or the Page. The following code examples illustrate how to configure rotationReference for an annotation.
+
+```javascript
+var diagramElement = document.getElementById('element');
+var diagram = diagramElement.ej2_instances[0];
+var annotation = [{
+    id: 'label1',
+    content: 'Annotation',
+    //To disable annotation rotation
+    rotationReference: 'Page'
+}]
+diagram.dataBind();
+```
+
+| Value | Description | Image |
+| -------- | -------- | -------- |
+| Page | When this option is set, the annotation remains fixed in its original orientation even if its parent node is rotated. | ![No_Rotation](images/page_rotationreference.gif) |
+| Parent | In this case, the annotation rotates along with its parent node. | ![Rotation](images/parent_rotationreference.gif)|