Squashed 'third_party/allwpilib_2017/' content from commit 35ac87d

Change-Id: I7bb6f5556c30d3f5a092e68de0be9c710c60c9f4
git-subtree-dir: third_party/allwpilib_2017
git-subtree-split: 35ac87d6ff8b7f061c4f18c9ea316e5dccd4888a
diff --git a/wpilibc/sim/include/simulation/SimEncoder.h b/wpilibc/sim/include/simulation/SimEncoder.h
new file mode 100644
index 0000000..1c0e9a7
--- /dev/null
+++ b/wpilibc/sim/include/simulation/SimEncoder.h
@@ -0,0 +1,39 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2014-2017. All Rights Reserved.                        */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#pragma once
+
+#include <string>
+
+#include <gazebo/common/Time.hh>
+#include <gazebo/transport/transport.hh>
+
+#include "simulation/gz_msgs/msgs.h"
+
+namespace frc {
+
+class SimEncoder {
+ public:
+  explicit SimEncoder(std::string topic);
+
+  void Reset();
+  void Start();
+  void Stop();
+  double GetPosition();
+  double GetVelocity();
+
+ private:
+  void sendCommand(std::string cmd);
+
+  double position, velocity;
+  gazebo::transport::SubscriberPtr posSub, velSub;
+  gazebo::transport::PublisherPtr commandPub;
+  void positionCallback(const gazebo::msgs::ConstFloat64Ptr& msg);
+  void velocityCallback(const gazebo::msgs::ConstFloat64Ptr& msg);
+};
+
+}  // namespace frc