Use explicit flatbuffer IDs in y2017 and newer.

Non-explicit ids are risky.  We've seen backwards incompatible
changes...

Change-Id: Id6ceebe031ac80430191f367635d0e951c3d2cbc
diff --git a/y2020/control_loops/superstructure/superstructure_goal.fbs b/y2020/control_loops/superstructure/superstructure_goal.fbs
index 9200082..792b6b4 100644
--- a/y2020/control_loops/superstructure/superstructure_goal.fbs
+++ b/y2020/control_loops/superstructure/superstructure_goal.fbs
@@ -5,10 +5,10 @@
 table ShooterGoal {
   // Angular velocity in rad/s of the slowest (lowest) wheel in the kicker.
   // Positive is shooting the ball.
-  velocity_accelerator:double;
+  velocity_accelerator:double (id: 0);
 
   // Angular velocity in rad/s of the flywheel. Positive is shooting.
-  velocity_finisher:double;
+  velocity_finisher:double (id: 1);
 }
 
 table Goal {
diff --git a/y2020/control_loops/superstructure/superstructure_output.fbs b/y2020/control_loops/superstructure/superstructure_output.fbs
index fd57825..005d930 100644
--- a/y2020/control_loops/superstructure/superstructure_output.fbs
+++ b/y2020/control_loops/superstructure/superstructure_output.fbs
@@ -2,35 +2,35 @@
 
 table Output {
   // Votage sent to the hood. Positive moves up.
-  hood_voltage:double;
+  hood_voltage:double (id: 0);
 
   // Voltage sent to motors on intake joint. Positive extends rollers.
-  intake_joint_voltage:double;
+  intake_joint_voltage:double (id: 1);
 
   // Voltage sent to rollers on intake. Positive rolls inward.
-  intake_roller_voltage:double;
+  intake_roller_voltage:double (id: 2);
 
-  //Voltage sent to the motors.
-  //Positive rotates counterclockwise from a birds eye view.
-  turret_voltage:double;
+  // Voltage sent to the motors.
+  // Positive rotates counterclockwise from a birds eye view.
+  turret_voltage:double (id: 3);
 
   // Voltage sent to the feeder belt. Positive is feeding.
-  feeder_voltage:double;
+  feeder_voltage:double (id: 4);
 
   // Voltage sent to the washing_machine and control panel spinner.
   // Positive runs the washing machine CCW facing the front of the robot, and
   // the spinner runs CCW from a top down view.
-  washing_machine_spinner_voltage:double;
+  washing_machine_spinner_voltage:double (id: 5);
 
   // Voltage sent to the kicker. Positive is shooting.
-  accelerator_left_voltage:double;
-  accelerator_right_voltage:double;
+  accelerator_left_voltage:double (id: 6);
+  accelerator_right_voltage:double (id: 7);
 
   // Voltage sent to the flywheel. Positive is shooting.
-  finisher_voltage:double;
+  finisher_voltage:double (id: 8);
 
   // Positive is deploying climber and to climb; cannot run in reverse
-  climber_voltage:double;
+  climber_voltage:double (id: 9);
 }
 
 root_type Output;
diff --git a/y2020/control_loops/superstructure/superstructure_position.fbs b/y2020/control_loops/superstructure/superstructure_position.fbs
index ed4ba18..f139381 100644
--- a/y2020/control_loops/superstructure/superstructure_position.fbs
+++ b/y2020/control_loops/superstructure/superstructure_position.fbs
@@ -4,29 +4,29 @@
 
 table ShooterPosition {
   // Flywheel angle in radians, positive is shooting.
-  theta_finisher:double;
+  theta_finisher:double (id: 0);
 
   // Kicker angle in radians of the slowest (lowest) wheel, positive is
   // accelerating the ball toward the shooter.
-  theta_accelerator_left:double;
-  theta_accelerator_right:double;
+  theta_accelerator_left:double (id: 1);
+  theta_accelerator_right:double (id: 2);
 }
 
 table Position {
   // Zero is at the horizontal, positive towards the front (radians).
-  hood:frc971.AbsolutePosition;
+  hood:frc971.AbsolutePosition (id: 0);
 
   // Position of the intake. 0 when four-bar is vertical, positive extended.
-  intake_joint:frc971.AbsolutePosition;
+  intake_joint:frc971.AbsolutePosition (id: 1);
 
   // See goal for definition of 0
-  turret:frc971.PotAndAbsolutePosition;
+  turret:frc971.PotAndAbsolutePosition (id: 2);
 
   // Position of the kicker and flywheel
-  shooter:ShooterPosition;
+  shooter:ShooterPosition (id: 3);
 
    // Position of the control panel, relative to start, positive counterclockwise from above.
-  control_panel:frc971.RelativePosition;
+  control_panel:frc971.RelativePosition (id: 4);
 }
 
 root_type Position;
diff --git a/y2020/control_loops/superstructure/superstructure_status.fbs b/y2020/control_loops/superstructure/superstructure_status.fbs
index dc6116c..fb94d32 100644
--- a/y2020/control_loops/superstructure/superstructure_status.fbs
+++ b/y2020/control_loops/superstructure/superstructure_status.fbs
@@ -6,63 +6,63 @@
 table FlywheelControllerStatus {
   // The current average velocity in radians/second over the last kHistoryLength
   // in shooter.h
-  avg_angular_velocity:double;
+  avg_angular_velocity:double (id: 0);
 
   // The current instantaneous filtered velocity in radians/second.
-  angular_velocity:double;
+  angular_velocity:double (id: 1);
 
   // The target speed selected by the lookup table or from manual override
   // Can be compared to velocity to determine if ready.
-  angular_velocity_goal:double;
+  angular_velocity_goal:double (id: 2);
 
   // Voltage error.
-  voltage_error:double;
+  voltage_error:double (id: 3);
 }
 
 table ShooterStatus {
   // The final wheel shooting the ball
-  finisher:FlywheelControllerStatus;
+  finisher:FlywheelControllerStatus (id: 0);
 
   // The subsystem to accelerate the ball before the finisher
   // Velocity is the fastest (top) wheel
-  accelerator_left:FlywheelControllerStatus;
-  accelerator_right:FlywheelControllerStatus;
+  accelerator_left:FlywheelControllerStatus (id: 1);
+  accelerator_right:FlywheelControllerStatus (id: 2);
 }
 
 table AimerStatus {
   // The current goal angle for the turret auto-tracking, in radians.
-  turret_position:double;
+  turret_position:double (id: 0);
   // The current goal velocity for the turret, in radians / sec.
-  turret_velocity:double;
+  turret_velocity:double (id: 1);
   // Whether we are currently aiming for the inner port.
-  aiming_for_inner_port:bool;
+  aiming_for_inner_port:bool (id: 2);
   // The current distance to the target, in meters.
-  target_distance:double;
+  target_distance:double (id: 3);
   // The current "shot distance." When shooting on the fly, this may be
   // different from the static distance to the target.
-  shot_distance:double;
+  shot_distance:double (id: 4);
 }
 
 table Status {
   // All subsystems know their location.
-  zeroed:bool;
+  zeroed:bool (id: 0);
 
   // If true, we have aborted. This is if one or all subsystem estops.
-  estopped:bool;
+  estopped:bool (id: 1);
 
   // Subsystem status.
-  hood:frc971.control_loops.AbsoluteEncoderProfiledJointStatus;
-  intake:frc971.control_loops.AbsoluteEncoderProfiledJointStatus;
-  turret:frc971.control_loops.PotAndAbsoluteEncoderProfiledJointStatus;
+  hood:frc971.control_loops.AbsoluteEncoderProfiledJointStatus (id: 2);
+  intake:frc971.control_loops.AbsoluteEncoderProfiledJointStatus (id: 3);
+  turret:frc971.control_loops.PotAndAbsoluteEncoderProfiledJointStatus (id: 4);
 
   // Shooter subsystem status.
-  shooter:ShooterStatus;
+  shooter:ShooterStatus (id: 5);
 
   // Status of the control_panel
-  control_panel:frc971.control_loops.RelativeEncoderProfiledJointStatus;
+  control_panel:frc971.control_loops.RelativeEncoderProfiledJointStatus (id: 6);
 
   // Status of the vision auto-tracking.
-  aimer:AimerStatus;
+  aimer:AimerStatus (id: 7);
 }
 
 root_type Status;
diff --git a/y2020/setpoint.fbs b/y2020/setpoint.fbs
index 5f1af72..74164e5 100644
--- a/y2020/setpoint.fbs
+++ b/y2020/setpoint.fbs
@@ -1,11 +1,11 @@
 namespace y2020.joysticks;
 
 table Setpoint {
-  accelerator:double;
+  accelerator:double (id: 0);
 
-  finisher:double;
+  finisher:double (id: 1);
 
-  hood:double;
+  hood:double (id: 2);
 }
 
 root_type Setpoint;
diff --git a/y2020/vision/sift/sift.fbs b/y2020/vision/sift/sift.fbs
index f38e0fe..5c44858 100644
--- a/y2020/vision/sift/sift.fbs
+++ b/y2020/vision/sift/sift.fbs
@@ -2,9 +2,9 @@
 
 // Represents the location of a keypoint in field coordinates.
 struct KeypointFieldLocation {
-  x:float;
-  y:float;
-  z:float;
+  x:float (id: 0);
+  y:float (id: 1);
+  z:float (id: 2);
 }
 
 // Represents a single feature extracted from an image.
@@ -18,70 +18,70 @@
   // The size of this depends on the parameters. It is width*width*hist_bins.
   // Currently we have width=4 and hist_bins=8, which results in a size of
   // 4*4*8=128.
-  descriptor:[ubyte];
+  descriptor:[ubyte] (id: 0);
 
   // Location of the keypoint.
-  x:float;
-  y:float;
+  x:float (id: 1);
+  y:float (id: 2);
 
   // Size of the keypoint neighborhood.
-  size:float;
+  size:float (id: 3);
 
   // Angle of the keypoint.
   // This is in [0,360) clockwise.
-  angle:float;
+  angle:float (id: 4);
 
   // How good of a keypoint this is.
-  response:float;
+  response:float (id: 5);
 
   // Which octave this keypoint is from.
-  octave:int;
+  octave:int (id: 6);
 
   // Where this feature's keypoint is on the field. This will only be filled out
   // for training features, not ones extracted from query images.
-  field_location:KeypointFieldLocation;
+  field_location:KeypointFieldLocation (id: 7);
 }
 
 // Represents a single match between a training image and a query image.
 struct Match {
   // The index of the feature for the query image.
-  query_feature:int;
+  query_feature:int (id: 0);
   // The index of the feature for the training image.
-  train_feature:int;
+  train_feature:int (id: 1);
   // How "good" the match is.
-  distance:float;
+  distance:float (id: 2);
 }
 
 // Represents all the matches between a single training image and a query
 // image.
 table ImageMatch {
-  matches:[Match];
+  matches:[Match] (id: 0);
   // The index of the training image within all the training images.
-  train_image:int;
+  train_image:int (id: 1);
 }
 
 table TransformationMatrix {
   // The matrix data for a row-major 4x4 homogeneous transformation matrix.
   // This implies the bottom row is (0, 0, 0, 1).
-  data:[float];
+  data:[float] (id: 0);
 }
 
 // Calibration information for a given camera on a given robot.
 table CameraCalibration {
   // The name of the camera node which this calibration data applies to.
-  node_name:string;
+  node_name:string (id: 0);
   // The team number of the robot which this calibration data applies to.
-  team_number:int;
+  team_number:int (id: 1);
 
   // Intrinsics for the camera.
   //
   // This is the standard OpenCV intrinsics matrix in row major order (3x3).
-  intrinsics:[float];
+  intrinsics:[float] (id: 2);
 
   // Fixed extrinsics for the camera. This transforms from camera coordinates to
   // robot coordinates. For example: multiplying (0, 0, 0, 1) by this results in
   // the position of the camera aperature in robot coordinates.
-  fixed_extrinsics:TransformationMatrix;
+  fixed_extrinsics:TransformationMatrix (id: 3);
 
   // Extrinsics for a camera on a turret. This will only be filled out for
   // applicable cameras. For turret-mounted cameras, fixed_extrinsics defines
@@ -97,13 +97,13 @@
   //   fixed_extrinsics
   //   rotation around the Z axis by the turret angle
   //   turret_extrinsics
-  turret_extrinsics:TransformationMatrix;
+  turret_extrinsics:TransformationMatrix (id: 4);
 
   // This is the standard OpenCV 5 parameter distortion coefficients
-  dist_coeffs:[float];
+  dist_coeffs:[float] (id: 5);
 
   // Timestamp for when the calibration was taken on the realtime clock.
-  calibration_timestamp:int64;
+  calibration_timestamp:int64 (id: 6);
 }
 
 // Contains the information the EKF wants from an image matched against a single
@@ -120,7 +120,7 @@
   // (0, 0, 0) is the aperture of the camera (we pretend it's an ideal pinhole
   // camera). Positive Z is out of the camera. Positive X and Y are right
   // handed, but which way they face depends on the camera extrinsics.
-  camera_to_target:TransformationMatrix;
+  camera_to_target:TransformationMatrix (id: 0);
 
   // Field coordinates of the target, represented as a transformation matrix
   // from the field to the target.
@@ -133,36 +133,36 @@
   //
   // The value here will be selected from a small, static set of targets we
   // train images on.
-  field_to_target:TransformationMatrix;
+  field_to_target:TransformationMatrix (id: 1);
 
   // The pose of the camera in the field coordinate frame
-  field_to_camera:TransformationMatrix;
+  field_to_camera:TransformationMatrix (id: 2);
 
   // 2D image coordinate representing target location on the matched image
-  query_target_point_x:float;
-  query_target_point_y:float;
+  query_target_point_x:float (id: 3);
+  query_target_point_y:float (id: 4);
   // Perceived radius of target circle
-  query_target_point_radius:float;
+  query_target_point_radius:float (id: 5);
 }
 
 table ImageMatchResult {
   // The matches from this image to each of the training images which matched.
   // Each member is against the same captured image.
-  image_matches:[ImageMatch];
+  image_matches:[ImageMatch] (id: 0);
 
   // The transformations for this image for each of the training images which
   // matched.
   // TODO(Brian): Include some kind of covariance information for these.
-  camera_poses:[CameraPose];
+  camera_poses:[CameraPose] (id: 1);
 
   // The features for this image.
-  features:[Feature];
+  features:[Feature] (id: 2);
 
   // Timestamp when the frame was captured.
-  image_monotonic_timestamp_ns:long;
+  image_monotonic_timestamp_ns:long (id: 3);
 
   // Information about the camera which took this image.
-  camera_calibration:CameraCalibration;
+  camera_calibration:CameraCalibration (id: 4);
 }
 
 root_type ImageMatchResult;
diff --git a/y2020/vision/sift/sift_training.fbs b/y2020/vision/sift/sift_training.fbs
index 12ad9b4..c093e3b 100644
--- a/y2020/vision/sift/sift_training.fbs
+++ b/y2020/vision/sift/sift_training.fbs
@@ -4,26 +4,26 @@
 
 // Represents a single image we train against.
 table TrainingImage {
-  features:[Feature];
+  features:[Feature] (id: 0);
 
   // Field coordinates of the target, represented as a transformation matrix
   // from the target to the field. See CameraPose in :sift_fbs for details of
   // the conventions of this.
-  field_to_target:TransformationMatrix;
+  field_to_target:TransformationMatrix (id: 1);
 
   // 2D image coordinate representing target location on the training image
-  target_point_x:float;
-  target_point_y:float;
+  target_point_x:float (id: 2);
+  target_point_y:float (id: 3);
   // Radius of target circle
-  target_point_radius:float;
+  target_point_radius:float (id: 4);
 }
 
 // Represents the information used to match incoming images against.
 table TrainingData {
-  images:[TrainingImage];
+  images:[TrainingImage] (id: 0);
 
   // Calibration information for all the cameras we know about.
-  camera_calibrations:[CameraCalibration];
+  camera_calibrations:[CameraCalibration] (id: 1);
 }
 
 root_type TrainingData;
diff --git a/y2020/vision/vision.fbs b/y2020/vision/vision.fbs
index 17dc4a4..e89a181 100644
--- a/y2020/vision/vision.fbs
+++ b/y2020/vision/vision.fbs
@@ -10,13 +10,13 @@
 //   * Order: row major (index 0 is upper left, index 1 is to its right)
 table CameraImage {
   // The number of rows in the image.
-  rows:int;
+  rows:int32 (id: 0);
   // The number of columns in the image.
-  cols:int;
+  cols:int32 (id: 1);
   // The image data.
-  data:[ubyte];
+  data:[ubyte] (id: 2);
   // Timestamp when the frame was captured. This is the end-of-frame timestamp.
-  monotonic_timestamp_ns:long;
+  monotonic_timestamp_ns:int64 (id: 3);
 }
 
 root_type CameraImage;