klips/esp/cpp/07_lcd-panel/main/display.h

#ifndef DISPLAY_H
#define DISPLAY_H

#include <widgets/label/lv_label.h>

#include <unordered_map>
#include <esp_timer.h>

#include "panel.h"

#define LVGL_TICK_PERIOD_MS    5
#define LVGL_TASK_STACK_SIZE   (4 * 1024)
#define LVGL_TASK_PRIORITY     2

class Display {
public:
  explicit Display(IPanelDevice &device);

  ~Display() = default;

  [[nodiscard]] inline const lv_display_t *get() const { return lv_display_; }

  [[nodiscard]] inline lv_display_t *get() { return lv_display_; }

  [[nodiscard]] inline const lv_display_t *operator*() const { return get(); }

  [[nodiscard]] inline lv_display_t *operator*() { return get(); }

  void set_text(const char *text,
                const char *name,
                lv_label_long_mode_t long_mode = LV_LABEL_LONG_SCROLL_CIRCULAR,
                lv_align_t align = LV_ALIGN_TOP_MID);

  static bool lvgl_flush_ready(esp_lcd_panel_io_handle_t panel,
                               esp_lcd_panel_io_event_data_t *data,
                               void *user_ctx);

  static void lvgl_flush_cb(lv_display_t *display,
                            const lv_area_t *area,
                            uint8_t *px_map);

  static void lvgl_increase_tick(void *arg);

  [[noreturn]] static void lvgl_port_task(void *arg);

private:
  void register_lvgl_tick_timer();

  Panel panel_;

  lv_display_t *lv_display_;

  // Draw buffer associated with the lv_display_t.
  void *lv_buf_;

  // Objects stored in the screen associated with this display.
  // @sa Display::set_text
  // @sa lv_display_get_screen_active
  std::unordered_map<const char *, lv_obj_t *> lv_objects_;

  // TODO: This could be a private struct
  esp_timer_handle_t lv_tick_timer_;

  struct ScopedLock {
    explicit ScopedLock() { _lock_acquire(&lv_lock_); }

    ~ScopedLock() { _lock_release(&lv_lock_); }

    // LVGL library is not thread-safe, this example calls LVGL APIs from tasks.
    // We must use a mutex to protect it.
    static _lock_t lv_lock_;
  };
};

#endif // DISPLAY_H