fix/feat: NI.AssignAuthority sends owner data + Example (#4032)

* fix: NI.AssignAuthority ensures owner data is sent

* feat: AssignAuthority example

Author: imerr

Assets/Mirror/Core/NetworkIdentity.cs

@@ -1558,6 +1558,19 @@ public bool AssignClientAuthority(NetworkConnectionToClient conn)
 
             clientAuthorityCallback?.Invoke(conn, this, true);
 
+            // If the connection is already observing the object we need to sync owner data only:
+            if (conn.observing.Contains(this))
+            {
+                foreach (NetworkBehaviour comp in NetworkBehaviours)
+                    if (comp.syncMode == SyncMode.Owner)
+                        comp.SetDirty();
+            }
+            else
+            {
+                // otherwise rebuild so the owner sees their NI without further delays
+                NetworkServer.RebuildObservers(this, false);
+            }
+            
             return true;
         }
 

Assets/Mirror/Examples/AssignAuthority.meta

@@ -0,0 +1,80 @@
+%YAML 1.1
+%TAG !u! tag:unity3d.com,2011:
+--- !u!21 &2100000
+Material:
+  serializedVersion: 8
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_Name: Object
+  m_Shader: {fileID: 46, guid: 0000000000000000f000000000000000, type: 0}
+  m_ValidKeywords: []
+  m_InvalidKeywords: []
+  m_LightmapFlags: 4
+  m_EnableInstancingVariants: 0
+  m_DoubleSidedGI: 0
+  m_CustomRenderQueue: -1
+  stringTagMap: {}
+  disabledShaderPasses: []
+  m_SavedProperties:
+    serializedVersion: 3
+    m_TexEnvs:
+    - _BumpMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailAlbedoMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailMask:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailNormalMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _EmissionMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _MainTex:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _MetallicGlossMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _OcclusionMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _ParallaxMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    m_Ints: []
+    m_Floats:
+    - _BumpScale: 1
+    - _Cutoff: 0.5
+    - _DetailNormalMapScale: 1
+    - _DstBlend: 0
+    - _GlossMapScale: 1
+    - _Glossiness: 0.5
+    - _GlossyReflections: 1
+    - _Metallic: 0
+    - _Mode: 0
+    - _OcclusionStrength: 1
+    - _Parallax: 0.02
+    - _SmoothnessTextureChannel: 0
+    - _SpecularHighlights: 1
+    - _SrcBlend: 1
+    - _UVSec: 0
+    - _ZWrite: 1
+    m_Colors:
+    - _Color: {r: 0.5, g: 0.5, b: 0.5, a: 1}
+    - _EmissionColor: {r: 0, g: 0, b: 0, a: 1}
+  m_BuildTextureStacks: []