Add touchwheel -> encoder adapter

1 files changed, 78 insertions, 0 deletions

diff --git a/src/drivers/relative_wheel.cpp b/src/drivers/relative_wheel.cpp
new file mode 100644
index 00000000..f64d213d
--- /dev/null
+++ b/src/drivers/relative_wheel.cpp
@@ -0,0 +1,78 @@
+/*
+ * Copyright 2023 jacqueline <me@jacqueline.id.au>
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#include "relative_wheel.hpp"
+
+#include <stdint.h>
+#include <cstdint>
+
+#include "esp_log.h"
+
+namespace drivers {
+
+RelativeWheel::RelativeWheel(TouchWheel *touch) 
+  :touch_(touch),
+  is_pressed_(false),
+  is_first_read_(true),
+  ticks_(0),
+  last_angle_(0) {}
+
+auto RelativeWheel::Update() -> void {
+  touch_->Update();
+  TouchWheelData d = touch_->GetTouchWheelData();
+  is_pressed_ = d.is_touched;
+
+  uint8_t new_angle = d.wheel_position;
+  if (is_first_read_) {
+    is_first_read_ = false;
+    last_angle_ = new_angle;
+    return;
+  }
+
+  // Work out the magnitude of travel.
+  uint8_t change_cw = last_angle_ - new_angle;
+  uint8_t change_ccw = new_angle - last_angle_;
+  int change = std::min(change_cw, change_ccw);
+
+  last_angle_ = new_angle;
+
+  // Round to eliminate noise.
+  if (change <= 2) {
+    ticks_ = 0;
+    return;
+  }
+
+  // Quantize into ticks.
+  change /= 4;
+
+  // Clamp to reliminate more noise.
+  if (change > 10) {
+    change = 0;
+  }
+
+  // Work out the direction of travel.
+  if (change_cw > change_ccw) {
+    change *= -1;
+  }
+
+  ticks_ = change;
+}
+
+auto RelativeWheel::is_pressed() -> bool {
+  return is_pressed_;
+}
+
+auto RelativeWheel::ticks() -> std::int_fast16_t {
+  int_fast16_t t = ticks_;
+  if (t != 0) {
+  ESP_LOGI("teeks", "ticks %d", t);
+  }
+  ticks_ = 0;
+  return t;
+}
+
+
+}  // namespace drivers