WIP decompose our giant LVGL driver into smaller classes

1 files changed, 81 insertions, 0 deletions

diff --git a/src/input/input_touch_wheel.cpp b/src/input/input_touch_wheel.cpp
new file mode 100644
index 00000000..302a17aa
--- /dev/null
+++ b/src/input/input_touch_wheel.cpp
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2024 jacqueline <me@jacqueline.id.au>
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#include "input_touch_wheel.hpp"
+#include <stdint.h>
+
+#include <cstdint>
+
+#include "hal/lv_hal_indev.h"
+
+#include "haptics.hpp"
+#include "input_device.hpp"
+#include "touchwheel.hpp"
+
+namespace input {
+
+TouchWheel::TouchWheel(drivers::TouchWheel& wheel)
+    : wheel_(wheel),
+      is_scrolling_(false),
+      sensitivity_(128),
+      threshold_(10),
+      is_first_read_(true),
+      last_angle_(0) {}
+
+auto TouchWheel::read(lv_indev_data_t* data) -> void {
+  wheel_.Update();
+  auto wheel_data = wheel_.GetTouchWheelData();
+  int8_t ticks = calculate_ticks(wheel_data);
+
+  if (!wheel_data.is_wheel_touched) {
+    // User has released the wheel.
+    is_scrolling_ = false;
+    data->enc_diff = 0;
+  } else if (ticks != 0) {
+    // User is touching the wheel, and has just passed the sensitivity
+    // threshold for a scroll tick.
+    is_scrolling_ = true;
+    data->enc_diff = ticks;
+  } else {
+    // User is touching the wheel, but hasn't moved.
+    data->enc_diff = 0;
+  }
+
+  if (!is_scrolling_ && wheel_data.is_button_touched) {
+    data->state = LV_INDEV_STATE_PRESSED;
+  } else {
+    data->state = LV_INDEV_STATE_RELEASED;
+  }
+}
+
+auto TouchWheel::calculate_ticks(const drivers::TouchWheelData& data)
+    -> int8_t {
+  if (!data.is_wheel_touched) {
+    is_first_read_ = true;
+    return 0;
+  }
+
+  uint8_t new_angle = data.wheel_position;
+  if (is_first_read_) {
+    is_first_read_ = false;
+    last_angle_ = new_angle;
+    return 0;
+  }
+
+  int delta = 128 - last_angle_;
+  uint8_t rotated_angle = new_angle + delta;
+  if (rotated_angle < 128 - threshold_) {
+    last_angle_ = new_angle;
+    return 1;
+  } else if (rotated_angle > 128 + threshold_) {
+    last_angle_ = new_angle;
+    return -1;
+  } else {
+    return 0;
+  }
+}
+
+}  // namespace input