Added call to CheckDisplayStartup and setting flag when DisplayConfig has received its first pose. This fixes the error when no HMD is connected.

Author: DuFF14

OSVR-Unity/Assets/OSVRUnity/src/DisplayController.cs

@@ -52,6 +52,7 @@ public class DisplayController : MonoBehaviour
             private uint _viewerCount;
             private bool _renderedStereo = false;
             private bool _displayConfigInitialized = false;
+            private bool _checkDisplayStartup = false;
             private Camera _camera;
             private bool _disabledCamera = true;
 
@@ -210,11 +211,19 @@ void OnPreCull()
                     //update the client
                     UpdateClient();
 
-                    //update the viewer's head pose
-                    viewer.UpdateViewerHeadPose(DisplayConfig.GetViewerPose(viewerIndex));
+                    //update poses once DisplayConfig is ready
+                    if (_checkDisplayStartup)
+                    {
+                        //update the viewer's head pose
+                        viewer.UpdateViewerHeadPose(DisplayConfig.GetViewerPose(viewerIndex));
 
-                    //each viewer update its eyes
-                    viewer.UpdateEyes();
+                        //each viewer update its eyes
+                        viewer.UpdateEyes();
+                    }
+                    else
+                    {
+                        _checkDisplayStartup = DisplayConfig.CheckDisplayStartup();
+                    }
                 }       
 
                 // Flag that we disabled the camera