Added new sample programs to the eclipse plugins for C++ and Java.

Modified examples.xml for the corresponding added programs.

Change-Id: I3d86c570f446ec8cf3013c58dd94215f2907bbb1

eclipse-plugins/edu.wpi.first.wpilib.plugins.cpp/resources/templates/examples/UltrasonicPID/src/Robot.cpp

@@ -0,0 +1,99 @@
+#include "WPILib.h"
+
+/**
+ * This is a sample program to demonstrate the use of a PID Controller with an ultrasonic
+ * sensor to reach and maintain a set distance from an object.
+ *
+ * WARNING: While it may look like a good choice to use for your code if you're inexperienced,
+ * don't. Unless you know what you are doing, complex code will be much more difficult under
+ * this system. Use IterativeRobot or Command-Based instead if you're new.
+ */
+class Robot: public SampleRobot {
+	AnalogInput *ultrasonic; //ultrasonic sensor
+	RobotDrive *myRobot;
+	PIDController *pidController;
+
+public:
+	const int ultrasonicChannel = 3; //analog input
+
+	//channels for motors
+	const int leftMotorChannel = 1;
+	const int rightMotorChannel = 0;
+	const int leftRearMotorChannel = 3;
+	const int rightRearMotorChannel = 2;
+
+	int holdDistance = 12; //distance in inches the robot wants to stay from an object
+
+	//proportional, integral, and derivative speed constants
+	//DANGER: when tuning PID constants, high/inappropriate values for pGain, iGain,
+	//and dGain may cause dangerous, uncontrollable, or undesired behavior!
+	const double pGain = 7, iGain = .018, dGain = 1.5;
+
+	//conversion factor specific to the sensor being used. For this sensor,
+	//the sensor returned values from 0.0V to 5.0V with a resolution of 9.8mV/in.
+	const double VoltsToInches = 0.0098;
+
+	//internal class to write to myRobot (a RobotDrive object) using a PIDOutput
+	class MyPIDOutput: public PIDOutput {
+	public:
+		RobotDrive* rd;
+		MyPIDOutput(RobotDrive *r)
+		{
+			rd = r;
+			rd->SetSafetyEnabled(false);
+		}
+		void PIDWrite(float output) {
+			rd->Drive(output, 0); //write to myRobot (RobotDrive) by reference
+		}
+	};
+
+	Robot() :
+		SampleRobot() {
+		//make objects for sensor and drive train
+		ultrasonic = new AnalogInput(ultrasonicChannel);
+		myRobot = new RobotDrive(new CANTalon(leftMotorChannel),
+					new CANTalon(leftRearMotorChannel),
+					new CANTalon(rightMotorChannel),
+					new CANTalon(rightRearMotorChannel));
+
+		//ultrasonic (AnalogInput) can be used as a PIDSource without modification,
+		//PIDOutput is an instance of the internal class MyPIDOutput made earlier
+		pidController = new PIDController(pGain, iGain, dGain, ultrasonic,
+				new MyPIDOutput(myRobot));
+
+	}
+
+	/**
+	 * Runs during autonomous.
+	 */
+	void Autonomous()
+	{
+
+	}
+
+	/**
+	 * Drives robot to set distance from an object using PID control and the ultrasonic
+	 * sensor.
+	 */
+	void OperatorControl() {
+		pidController->SetSetpoint(holdDistance * VoltsToInches); //set setpoint to 12 inches
+
+		//set expected range to 0-24 inches; e.g. at 24 inches from object go full
+		//forward, at 0 inches from object go full backward.
+		pidController->SetInputRange(0, 24 * VoltsToInches);
+
+		while (IsOperatorControl() && IsEnabled()) {
+			pidController->Enable(); //begin PID control
+		}
+	}
+
+	/**
+	 * Runs during test mode.
+	 */
+	void Test()
+	{
+
+	}
+};
+
+START_ROBOT_CLASS(Robot);