Fix ProfiledPIDController profile direction for continuous input (#2279)

Previously, it could take the long way around. This recomputes the
profile goal with the shortest error, thus taking the shortest path.

Also removed the setpoint clamping from PIDController::SetSetpoint()
because it's unnecessary to make PIDController behave correctly for
a modular arithmetic input, and it breaks the setpoint calculation in
ProfiledPIDController otherwise.

Fixes #2277.

wpilibc/src/main/native/include/frc/controller/PIDController.h

@@ -140,6 +140,11 @@ class PIDController : public frc::Sendable,
    */
   void DisableContinuousInput();
 
+  /**
+   * Returns true if continuous input is enabled.
+   */
+  bool IsContinuousInputEnabled() const;
+
   /**
    * Sets the minimum and maximum values for the integrator.
    *
@@ -193,16 +198,6 @@ class PIDController : public frc::Sendable,
 
   void InitSendable(frc::SendableBuilder& builder) override;
 
- protected:
-  /**
-   * Wraps error around for continuous inputs. The original error is returned if
-   * continuous mode is disabled.
-   *
-   * @param error The current error of the PID controller.
-   * @return Error for continuous inputs.
-   */
-  double GetContinuousError(double error) const;
-
  private:
   // Factor for "proportional" control
   double m_Kp;
@@ -220,15 +215,10 @@ class PIDController : public frc::Sendable,
 
   double m_minimumIntegral = -1.0;
 
-  // Maximum input - limit setpoint to this
   double m_maximumInput = 0;
 
-  // Minimum input - limit setpoint to this
   double m_minimumInput = 0;
 
-  // Input range - difference between maximum and minimum
-  double m_inputRange = 0;
-
   // Do the endpoints wrap around? eg. Absolute encoder
   bool m_continuous = false;
 
@@ -248,14 +238,6 @@ class PIDController : public frc::Sendable,
   double m_velocityTolerance = std::numeric_limits<double>::infinity();
 
   double m_setpoint = 0;
-
-  /**
-   * Sets the minimum and maximum values expected from the input.
-   *
-   * @param minimumInput The minimum value expected from the input.
-   * @param maximumInput The maximum value expected from the input.
-   */
-  void SetInputRange(double minimumInput, double maximumInput);
 };
 
 }  // namespace frc2