Feature: joystick weights (#21883)

Co-authored-by: Nick Brassel <nick@tzarc.org>

2 files changed, 77 insertions, 10 deletions

diff --git a/docs/feature_pointing_device.md b/docs/feature_pointing_device.md
index 0ac0069ff8..fad9056e10 100644
--- a/docs/feature_pointing_device.md
+++ b/docs/feature_pointing_device.md
@@ -69,10 +69,29 @@ The Analog Joystick is an analog (ADC) driven sensor.  There are a variety of jo
 | `ANALOG_JOYSTICK_Y_AXIS_PIN`      | (Required) The pin used for the horizontal/Y axis.                         | _not defined_ |
 | `ANALOG_JOYSTICK_AXIS_MIN`        | (Optional) Sets the lower range to be considered movement.                 | `0`           |
 | `ANALOG_JOYSTICK_AXIS_MAX`        | (Optional) Sets the upper range to be considered movement.                 | `1023`        |
+| `ANALOG_JOYSTICK_AUTO_AXIS`       | (Optional) Sets ranges to be considered movement automatically.            | _not defined_ |
 | `ANALOG_JOYSTICK_SPEED_REGULATOR` | (Optional) The divisor used to slow down movement. (lower makes it faster) | `20`          |
 | `ANALOG_JOYSTICK_READ_INTERVAL`   | (Optional) The interval in milliseconds between reads.                     | `10`          |
 | `ANALOG_JOYSTICK_SPEED_MAX`       | (Optional) The maximum value used for motion.                              | `2`           |
 | `ANALOG_JOYSTICK_CLICK_PIN`       | (Optional) The pin wired up to the press switch of the analog stick.       | _not defined_ |
+| `ANALOG_JOYSTICK_WEIGHTS`         | (Optional) Use custom weights for lever positions.                         | _not defined_ |
+| `ANALOG_JOYSTICK_CUTOFF`          | (Optional) Cut off movement when joystick returns to start position.       | _not defined_ |
+
+If `ANALOG_JOYSTICK_AUTO_AXIS` is used, then `ANALOG_JOYSTICK_AXIS_MIN` and `ANALOG_JOYSTICK_AXIS_MAX` are ignored.
+
+By default analog joystick implementation uses `x^2` weighting for lever positions. `ANALOG_JOYSTICK_WEIGHTS` allows to experiment with different configurations that might feel better.
+
+E.g. This is weights for `((x-0.4)^3+0.064)/0.282`:
+
+```c
+#define ANALOG_JOYSTICK_WEIGHTS {0,2,4,5,7,8,9,10,12,13,14,15,15,16,17,18,18,19,19,20,20,21,21,21,22,22,22,22,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,23,24,24,24,24,24,24,25,25,25,26,26,26,27,28,28,29,29,30,31,32,33,34,35,36,37,38,40,41,43,44,46,48,49,51,53,56,58,60,62,65,68,70,73,76,79,82,85,89,92,96,100}
+```
+
+You can use following JS code to generate weights for different formulas:
+
+```js
+JSON.stringify(Array.from(Array(101).keys()).map(x => Math.ceil((((x/100-0.4)**3+0.064)/0.282*100))))
+```
 
 ### Azoteq IQS5XX Trackpad
 
diff --git a/drivers/sensors/analog_joystick.c b/drivers/sensors/analog_joystick.c
index 12256a8e7a..4aede4eacd 100644
--- a/drivers/sensors/analog_joystick.c
+++ b/drivers/sensors/analog_joystick.c
@@ -22,17 +22,28 @@
 #include <stdlib.h>
 
 // Set Parameters
+#ifndef ANALOG_JOYSTICK_AUTO_AXIS
 uint16_t minAxisValue = ANALOG_JOYSTICK_AXIS_MIN;
 uint16_t maxAxisValue = ANALOG_JOYSTICK_AXIS_MAX;
+#else
+int16_t minAxisValues[2];
+int16_t maxAxisValues[2];
+#endif
 
 uint8_t maxCursorSpeed = ANALOG_JOYSTICK_SPEED_MAX;
 uint8_t speedRegulator = ANALOG_JOYSTICK_SPEED_REGULATOR; // Lower Values Create Faster Movement
 
+#ifdef ANALOG_JOYSTICK_WEIGHTS
+int8_t weights[101] = ANALOG_JOYSTICK_WEIGHTS;
+#endif
+
 int16_t xOrigin, yOrigin;
 
 uint16_t lastCursor = 0;
 
-int16_t axisCoordinate(pin_t pin, uint16_t origin) {
+uint8_t prevValues[2] = {0, 0};
+
+int16_t axisCoordinate(pin_t pin, uint16_t origin, uint8_t axis) {
     int8_t  direction;
     int16_t distanceFromOrigin;
     int16_t range;
@@ -43,12 +54,27 @@ int16_t axisCoordinate(pin_t pin, uint16_t origin) {
         return 0;
     } else if (origin > position) {
         distanceFromOrigin = origin - position;
-        range              = origin - minAxisValue;
-        direction          = -1;
+#ifdef ANALOG_JOYSTICK_AUTO_AXIS
+        if (position < minAxisValues[axis]) {
+            minAxisValues[axis] = position;
+        }
+        range = origin - minAxisValues[axis];
+#else
+        range = origin - minAxisValue;
+#endif
+        direction = -1;
     } else {
         distanceFromOrigin = position - origin;
-        range              = maxAxisValue - origin;
-        direction          = 1;
+
+#ifdef ANALOG_JOYSTICK_AUTO_AXIS
+        if (position > maxAxisValues[axis]) {
+            maxAxisValues[axis] = position;
+        }
+        range = maxAxisValues[axis] - origin;
+#else
+        range = maxAxisValue - origin;
+#endif
+        direction = 1;
     }
 
     float   percent    = (float)distanceFromOrigin / range;
@@ -62,14 +88,29 @@ int16_t axisCoordinate(pin_t pin, uint16_t origin) {
     }
 }
 
-int8_t axisToMouseComponent(pin_t pin, int16_t origin, uint8_t maxSpeed) {
-    int16_t coordinate = axisCoordinate(pin, origin);
+int8_t axisToMouseComponent(pin_t pin, int16_t origin, uint8_t maxSpeed, uint8_t axis) {
+    int16_t coordinate = axisCoordinate(pin, origin, axis);
+    int8_t  result;
+#ifndef ANALOG_JOYSTICK_WEIGHTS
     if (coordinate != 0) {
         float percent = (float)coordinate / 100;
-        return percent * maxCursorSpeed * (abs(coordinate) / speedRegulator);
+        result        = percent * maxCursorSpeed * (abs(coordinate) / speedRegulator);
     } else {
         return 0;
     }
+#else
+    result = weights[abs(coordinate)] * (coordinate < 0 ? -1 : 1) * maxCursorSpeed / speedRegulator;
+#endif
+
+#ifdef ANALOG_JOYSTICK_CUTOFF
+    uint8_t pv       = prevValues[axis];
+    prevValues[axis] = abs(result);
+    if (pv > abs(result)) {
+        return 0;
+    }
+#endif
+
+    return result;
 }
 
 report_analog_joystick_t analog_joystick_read(void) {
@@ -77,8 +118,8 @@ report_analog_joystick_t analog_joystick_read(void) {
 
     if (timer_elapsed(lastCursor) > ANALOG_JOYSTICK_READ_INTERVAL) {
         lastCursor = timer_read();
-        report.x   = axisToMouseComponent(ANALOG_JOYSTICK_X_AXIS_PIN, xOrigin, maxCursorSpeed);
-        report.y   = axisToMouseComponent(ANALOG_JOYSTICK_Y_AXIS_PIN, yOrigin, maxCursorSpeed);
+        report.x   = axisToMouseComponent(ANALOG_JOYSTICK_X_AXIS_PIN, xOrigin, maxCursorSpeed, 0);
+        report.y   = axisToMouseComponent(ANALOG_JOYSTICK_Y_AXIS_PIN, yOrigin, maxCursorSpeed, 1);
     }
 #ifdef ANALOG_JOYSTICK_CLICK_PIN
     report.button = !readPin(ANALOG_JOYSTICK_CLICK_PIN);
@@ -93,4 +134,11 @@ void analog_joystick_init(void) {
     // Account for drift
     xOrigin = analogReadPin(ANALOG_JOYSTICK_X_AXIS_PIN);
     yOrigin = analogReadPin(ANALOG_JOYSTICK_Y_AXIS_PIN);
+
+#ifdef ANALOG_JOYSTICK_AUTO_AXIS
+    minAxisValues[0] = xOrigin - 100;
+    minAxisValues[1] = yOrigin - 100;
+    maxAxisValues[0] = xOrigin + 100;
+    maxAxisValues[1] = yOrigin + 100;
+#endif
 }