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// Copyright (c) FIRST and other WPILib contributors.
// Open Source Software; you can modify and/or share it under the terms of
// the WPILib BSD license file in the root directory of this project.
#pragma once
#include <memory>
#include <wpi/sendable/Sendable.h>
#include <wpi/sendable/SendableHelper.h>
#include "frc/AnalogInput.h"
namespace frc {
/**
* Class for reading analog potentiometers. Analog potentiometers read in an
* analog voltage that corresponds to a position. The position is in whichever
* units you choose, by way of the scaling and offset constants passed to the
* constructor.
*/
class AnalogPotentiometer : public wpi::Sendable,
public wpi::SendableHelper<AnalogPotentiometer> {
public:
/**
* Construct an Analog Potentiometer object from a channel number.
*
* Use the fullRange and offset values so that the output produces meaningful
* values. I.E: you have a 270 degree potentiometer and you want the output to
* be degrees with the halfway point as 0 degrees. The fullRange value is
* 270.0 degrees and the offset is -135.0 since the halfway point after
* scaling is 135 degrees.
*
* This will calculate the result from the fullRange times the fraction of the
* supply voltage, plus the offset.
*
* @param channel The Analog Input channel number on the roboRIO the
* potentiometer is plugged into. 0-3 are on-board and 4-7
* are on the MXP port.
* @param fullRange The value (in desired units) representing the full
* 0-5V range of the input.
* @param offset The value (in desired units) representing the
* angular output at 0V.
*/
explicit AnalogPotentiometer(int channel, double fullRange = 1.0,
double offset = 0.0);
/**
* Construct an Analog Potentiometer object from an existing Analog Input
* pointer.
*
* Use the fullRange and offset values so that the output produces meaningful
* values. I.E: you have a 270 degree potentiometer and you want the output to
* be degrees with the halfway point as 0 degrees. The fullRange value is
* 270.0 degrees and the offset is -135.0 since the halfway point after
* scaling is 135 degrees.
*
* This will calculate the result from the fullRange times the fraction of the
* supply voltage, plus the offset.
*
* @param input The existing Analog Input pointer
* @param fullRange The value (in desired units) representing the full
* 0-5V range of the input.
* @param offset The value (in desired units) representing the
* angular output at 0V.
*/
explicit AnalogPotentiometer(AnalogInput* input, double fullRange = 1.0,
double offset = 0.0);
/**
* Construct an Analog Potentiometer object from an existing Analog Input
* pointer.
*
* Use the fullRange and offset values so that the output produces meaningful
* values. I.E: you have a 270 degree potentiometer and you want the output to
* be degrees with the halfway point as 0 degrees. The fullRange value is
* 270.0 degrees and the offset is -135.0 since the halfway point after
* scaling is 135 degrees.
*
* This will calculate the result from the fullRange times the fraction of the
* supply voltage, plus the offset.
*
* @param input The existing Analog Input pointer
* @param fullRange The value (in desired units) representing the full
* 0-5V range of the input.
* @param offset The value (in desired units) representing the
* angular output at 0V.
*/
explicit AnalogPotentiometer(std::shared_ptr<AnalogInput> input,
double fullRange = 1.0, double offset = 0.0);
~AnalogPotentiometer() override = default;
AnalogPotentiometer(AnalogPotentiometer&&) = default;
AnalogPotentiometer& operator=(AnalogPotentiometer&&) = default;
/**
* Get the current reading of the potentiometer.
*
* @return The current position of the potentiometer (in the units used for
* fullRange and offset).
*/
double Get() const;
void InitSendable(wpi::SendableBuilder& builder) override;
private:
std::shared_ptr<AnalogInput> m_analog_input;
double m_fullRange, m_offset;
};
} // namespace frc