Update camera track for unique targets and pgains.

Signed-off-by: Benjamin Perseghetti <[email protected]>

proto/gz/msgs/cameratrack.proto

@@ -31,19 +31,27 @@ message CameraTrack
 {
   enum TrackMode
   {
+    /// \brief Defaults to no tracking mode.
+    NONE              = 0;
     /// \brief TRACK observes a target from fixed x,y,z world camera point with pgain allowing only for orientation change.
-    TRACK             = 0;
+    TRACK             = 1;
     /// \brief FOLLOW moves with a target with an offset x,y,z camera and following pgain.
-    FOLLOW            = 1;
+    FOLLOW            = 2;
     /// \brief FOLLOW_FREE_LOOK moves with a target with an offset x,y,z camera and following pgain but allows for changing orientation for free looking around.
-    FOLLOW_FREE_LOOK  = 2;
+    FOLLOW_FREE_LOOK  = 3;
+    /// \brief FOLLOW_LOOK_AT moves with a target with an offset x,y,z camera and following pgain while looking at a specified target.
+    FOLLOW_LOOK_AT    = 4;
+    /// \brief USE_LAST updates offsets and pgains without changing the fundamental track mode or target(s)
+    USE_LAST          = 5;
   }
 
   /// \brief Optional header data
-  Header header         = 1;
-  TrackMode track_mode  = 2;
-  string target         = 3;
-  Vector3d offset       = 4;
-  Vector3d track_pose   = 5;
-  double pgain          = 6;
+  Header header           = 1;
+  TrackMode track_mode    = 2;
+  string follow_target    = 3;
+  string track_target     = 4;
+  Vector3d follow_offset  = 5;
+  Vector3d track_offset   = 6;
+  double follow_pgain     = 7;
+  double track_pgain      = 8;
 }