feat(t-deck): Add methods / tests for getting current rotated display size, use it to update display when it rotates in example (#554)

Author: finger563

components/t-deck/example/main/t_deck_example.cpp

@@ -27,7 +27,18 @@ extern "C" void app_main(void) {
   espp::TDeck &tdeck = espp::TDeck::get();
   tdeck.set_log_level(espp::Logger::Verbosity::INFO);
 
+  lv_obj_t *bg = nullptr;
+
   static auto rotation = LV_DISPLAY_ROTATION_0;
+  static auto rotate_display = [&]() {
+    std::lock_guard<std::recursive_mutex> lock(lvgl_mutex);
+    clear_circles();
+    rotation = static_cast<lv_display_rotation_t>((static_cast<int>(rotation) + 1) % 4);
+    lv_display_t *disp = lv_display_get_default();
+    lv_disp_set_rotation(disp, rotation);
+    // update the size of the screen
+    lv_obj_set_size(bg, tdeck.rotated_display_width(), tdeck.rotated_display_height());
+  };
 
   auto keypress_callback = [&](uint8_t key) {
     logger.info("Key pressed: {}", key);
@@ -41,9 +52,7 @@ extern "C" void app_main(void) {
       logger.info("Rotating display");
       std::lock_guard<std::recursive_mutex> lock(lvgl_mutex);
       clear_circles();
-      rotation = static_cast<lv_display_rotation_t>((static_cast<int>(rotation) + 1) % 4);
-      lv_display_t *disp = lv_display_get_default();
-      lv_disp_set_rotation(disp, rotation);
+      rotate_display();
     } else if (key == 'm') {
       // 'm' key will toggle audio mute
       logger.info("Toggling mute");
@@ -126,7 +135,7 @@ extern "C" void app_main(void) {
   }
 
   // set the background color to black
-  lv_obj_t *bg = lv_obj_create(lv_screen_active());
+  bg = lv_obj_create(lv_screen_active());
   lv_obj_set_size(bg, tdeck.lcd_width(), tdeck.lcd_height());
   lv_obj_set_style_bg_color(bg, lv_color_make(0, 0, 0), 0);
 
@@ -147,15 +156,7 @@ extern "C" void app_main(void) {
   // center the text in the button
   lv_obj_align(label_btn, LV_ALIGN_CENTER, 0, 0);
   lv_obj_add_event_cb(
-      btn,
-      [](auto event) {
-        std::lock_guard<std::recursive_mutex> lock(lvgl_mutex);
-        clear_circles();
-        rotation = static_cast<lv_display_rotation_t>((static_cast<int>(rotation) + 1) % 4);
-        lv_display_t *disp = lv_display_get_default();
-        lv_disp_set_rotation(disp, rotation);
-      },
-      LV_EVENT_PRESSED, nullptr);
+      btn, [](auto event) { rotate_display(); }, LV_EVENT_PRESSED, nullptr);
 
   // disable scrolling on the screen (so that it doesn't behave weirdly when
   // rotated and drawing with your finger)

components/t-deck/include/t-deck.hpp

@@ -317,6 +317,22 @@ class TDeck : public BaseComponent {
   /// \return The GPIO pin for the LCD data/command signal
   static constexpr auto get_lcd_dc_gpio() { return lcd_dc_io; }
 
+  /// Get the display width in pixels
+  /// \return The display width in pixels
+  static constexpr size_t display_width() { return lcd_width_; }
+
+  /// Get the display height in pixels
+  /// \return The display height in pixels
+  static constexpr size_t display_height() { return lcd_height_; }
+
+  /// Get the display width in pixels, according to the current orientation
+  /// \return The display width in pixels, according to the current orientation
+  size_t rotated_display_width() const;
+
+  /// Get the display height in pixels, according to the current orientation
+  /// \return The display height in pixels, according to the current orientation
+  size_t rotated_display_height() const;
+
   /// Get a shared pointer to the display
   /// \return A shared pointer to the display
   std::shared_ptr<Display<Pixel>> display() const;

components/t-deck/src/t-deck.cpp

@@ -543,3 +543,33 @@ float TDeck::brightness() const {
   }
   return 0.0f;
 }
+
+size_t TDeck::rotated_display_width() const {
+  auto rotation = lv_display_get_rotation(lv_display_get_default());
+  switch (rotation) {
+  // swap
+  case LV_DISPLAY_ROTATION_90:
+  case LV_DISPLAY_ROTATION_270:
+    return lcd_height_;
+  // as configured
+  case LV_DISPLAY_ROTATION_0:
+  case LV_DISPLAY_ROTATION_180:
+  default:
+    return lcd_width_;
+  }
+}
+
+size_t TDeck::rotated_display_height() const {
+  auto rotation = lv_display_get_rotation(lv_display_get_default());
+  switch (rotation) {
+  // swap
+  case LV_DISPLAY_ROTATION_90:
+  case LV_DISPLAY_ROTATION_270:
+    return lcd_width_;
+  // as configured
+  case LV_DISPLAY_ROTATION_0:
+  case LV_DISPLAY_ROTATION_180:
+  default:
+    return lcd_height_;
+  }
+}