From de2a883115fb736c7b75417f55a1c800718b087c Mon Sep 17 00:00:00 2001
From: "A. Craig West" <acraigwest@gmail.com>
Date: Mon, 28 Feb 2022 21:08:57 -0500
Subject: [PATCH] Changes to make AccelStepper more subclassable. These changes
 are largely oriented to implementing new step-scheduling algorithms.

---
 src/AccelStepper.cpp | 29 +++++++++++++++++++++++++++--
 src/AccelStepper.h   | 28 ++++++++++++++++++++++------
 2 files changed, 49 insertions(+), 8 deletions(-)

diff --git a/src/AccelStepper.cpp b/src/AccelStepper.cpp
index 093d56d..a093b73 100644
--- a/src/AccelStepper.cpp
+++ b/src/AccelStepper.cpp
@@ -94,7 +94,8 @@ void AccelStepper::setCurrentPosition(long position)
     _speed = 0.0;
 }
 
-void AccelStepper::computeNewSpeed()
+// Subclasses can override
+unsigned long AccelStepper::computeNewSpeed()
 {
     long distanceTo = distanceToGo(); // +ve is clockwise from curent location
 
@@ -106,7 +107,7 @@ void AccelStepper::computeNewSpeed()
 	_stepInterval = 0;
 	_speed = 0.0;
 	_n = 0;
-	return;
+	return _stepInterval;
     }
 
     if (distanceTo > 0)
@@ -174,6 +175,7 @@ void AccelStepper::computeNewSpeed()
     Serial.println(stepsToStop);
     Serial.println("-----");
 #endif
+    return _stepInterval;
 }
 
 // Run the motor to implement speed and acceleration in order to proceed to the target position
@@ -295,6 +297,11 @@ void AccelStepper::setAcceleration(float acceleration)
     }
 }
 
+float   AccelStepper::acceleration()
+{
+    return _acceleration;
+}
+
 void AccelStepper::setSpeed(float speed)
 {
     if (speed == _speed)
@@ -350,6 +357,24 @@ void AccelStepper::step(long step)
     }
 }
 
+long AccelStepper::stepForward()
+{
+    // Clockwise
+    _currentPos += 1;
+	step(_currentPos);
+	_lastStepTime = micros();
+    return _currentPos;
+}
+
+long AccelStepper::stepBackward()
+{
+    // Counter-clockwise
+    _currentPos -= 1;
+	step(_currentPos);
+	_lastStepTime = micros();
+    return _currentPos;
+}
+
 // You might want to override this to implement eg serial output
 // bit 0 of the mask corresponds to _pin[0]
 // bit 1 of the mask corresponds to _pin[1]
diff --git a/src/AccelStepper.h b/src/AccelStepper.h
index 5ab5aba..f63fd79 100644
--- a/src/AccelStepper.h
+++ b/src/AccelStepper.h
@@ -429,6 +429,11 @@ class AccelStepper
     /// root to be calculated. Dont call more ofthen than needed
     void    setAcceleration(float acceleration);
 
+    /// Returns the acceleration/deceleration rate configured for this stepper
+    /// that was previously set by setAcceleration();
+    /// \return The currently configured acceleration/deceleration
+    float   acceleration();
+
     /// Sets the desired constant speed for use with runSpeed().
     /// \param[in] speed The desired constant speed in steps per
     /// second. Positive is clockwise. Speeds of more than 1000 steps per
@@ -471,7 +476,7 @@ class AccelStepper
     /// position. Dont use this in event loops, since it blocks.
     void    runToPosition();
 
-    /// Runs at the currently selected speed until the target position is reached.
+    /// Runs at the currently selected speed unless the target position is reached.
     /// Does not implement accelerations.
     /// \return true if it stepped
     boolean runSpeedToPosition();
@@ -551,7 +556,8 @@ class AccelStepper
     /// \li  after change to acceleration through setAcceleration()
     /// \li  after change to target position (relative or absolute) through
     /// move() or moveTo()
-    void           computeNewSpeed();
+    /// \return the new step interval
+    virtual unsigned long computeNewSpeed();
 
     /// Low level function to set the motor output pins
     /// bit 0 of the mask corresponds to _pin[0]
@@ -567,6 +573,16 @@ class AccelStepper
     /// \param[in] step The current step phase number (0 to 7)
     virtual void   step(long step);
 
+    /// Called to execute a clockwise(+) step. Only called when a new step is
+    /// required. This increments the _currentPos and calls step()
+    /// \return the updated current position
+    long   stepForward();
+
+    /// Called to execute a counter-clockwise(-) step. Only called when a new step is
+    /// required. This decrements the _currentPos and calls step()
+    /// \return the updated current position
+    long   stepBackward();
+
     /// Called to execute a step using stepper functions (pins = 0) Only called when a new step is
     /// required. Calls _forward() or _backward() to perform the step
     /// \param[in] step The current step phase number (0 to 7)
@@ -618,6 +634,10 @@ class AccelStepper
     /// Protected because some peoples subclasses need it to be so
     boolean _direction; // 1 == CW
     
+    /// The current interval between steps in microseconds.
+    /// 0 means the motor is currently stopped with _speed == 0
+    unsigned long  _stepInterval;
+
 private:
     /// Number of pins on the stepper motor. Permits 2 or 4. 2 pins is a
     /// bipolar, and 4 pins is a unipolar.
@@ -650,10 +670,6 @@ class AccelStepper
     float          _acceleration;
     float          _sqrt_twoa; // Precomputed sqrt(2*_acceleration)
 
-    /// The current interval between steps in microseconds.
-    /// 0 means the motor is currently stopped with _speed == 0
-    unsigned long  _stepInterval;
-
     /// The last step time in microseconds
     unsigned long  _lastStepTime;