]> Repositories - hackapet/Adafruit_Blinka_Displayio.git/blobdiff - displayio/_display.py
Add root_group property to display
[hackapet/Adafruit_Blinka_Displayio.git] / displayio / _display.py
index da94fb2bc433a8f0c769cffc1af70256b26f749f..a3da5c5a031a83729806dc7f3a0f6365e9d4d0a4 100644 (file)
@@ -18,20 +18,15 @@ displayio for Blinka
 """
 
 import time
-import struct
-import threading
 from typing import Optional
-from dataclasses import astuple
 import digitalio
-from PIL import Image
-import numpy
 import microcontroller
-import circuitpython_typing
+from circuitpython_typing import WriteableBuffer, ReadableBuffer
 from ._displaycore import _DisplayCore
 from ._displaybus import _DisplayBus
 from ._colorconverter import ColorConverter
-from ._group import Group
-from ._structs import RectangleStruct
+from ._group import Group, circuitpython_splash
+from ._area import Area
 from ._constants import (
     CHIP_SELECT_TOGGLE_EVERY_BYTE,
     CHIP_SELECT_UNTOUCHED,
@@ -39,16 +34,16 @@ from ._constants import (
     DISPLAY_DATA,
     BACKLIGHT_IN_OUT,
     BACKLIGHT_PWM,
+    NO_COMMAND,
+    DELAY,
 )
 
 __version__ = "0.0.0+auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_Blinka_displayio.git"
 
-displays = []
-
 
 class Display:
-    # pylint: disable=too-many-instance-attributes
+    # pylint: disable=too-many-instance-attributes, too-many-statements
     """This initializes a display and connects it into CircuitPython. Unlike other objects
     in CircuitPython, Display objects live until ``displayio.release_displays()`` is called.
     This is done so that CircuitPython can use the display itself.
@@ -60,7 +55,7 @@ class Display:
     def __init__(
         self,
         display_bus: _DisplayBus,
-        init_sequence: circuitpython_typing.ReadableBuffer,
+        init_sequence: ReadableBuffer,
         *,
         width: int,
         height: int,
@@ -79,16 +74,14 @@ class Display:
         backlight_pin: Optional[microcontroller.Pin] = None,
         brightness_command: Optional[int] = None,
         brightness: float = 1.0,
-        auto_brightness: bool = False,
         single_byte_bounds: bool = False,
         data_as_commands: bool = False,
         auto_refresh: bool = True,
         native_frames_per_second: int = 60,
         backlight_on_high: bool = True,
         SH1107_addressing: bool = False,
-        set_vertical_scroll: int = 0,
     ):
-        # pylint: disable=unused-argument,too-many-locals,invalid-name
+        # pylint: disable=too-many-locals,invalid-name, too-many-branches
         """Create a Display object on the given display bus (`displayio.FourWire` or
         `paralleldisplay.ParallelBus`).
 
@@ -118,11 +111,21 @@ class Display:
         The initialization sequence should always leave the display memory access inline with
         the scan of the display to minimize tearing artifacts.
         """
+
+        if rotation % 90 != 0:
+            raise ValueError("Display rotation must be in 90 degree increments")
+
+        if SH1107_addressing and color_depth != 1:
+            raise ValueError("color_depth must be 1 when SH1107_addressing is True")
+
+        # Turn off auto-refresh as we init
+        self._auto_refresh = False
         ram_width = 0x100
         ram_height = 0x100
         if single_byte_bounds:
             ram_width = 0xFF
             ram_height = 0xFF
+
         self._core = _DisplayCore(
             bus=display_bus,
             width=width,
@@ -138,63 +141,44 @@ class Display:
             bytes_per_cell=bytes_per_cell,
             reverse_pixels_in_byte=reverse_pixels_in_byte,
             reverse_bytes_in_word=reverse_bytes_in_word,
+            column_command=set_column_command,
+            row_command=set_row_command,
+            set_current_column_command=NO_COMMAND,
+            set_current_row_command=NO_COMMAND,
+            data_as_commands=data_as_commands,
+            always_toggle_chip_select=False,
+            sh1107_addressing=(SH1107_addressing and color_depth == 1),
+            address_little_endian=False,
         )
 
-        self._set_column_command = set_column_command
-        self._set_row_command = set_row_command
         self._write_ram_command = write_ram_command
         self._brightness_command = brightness_command
-        self._data_as_commands = data_as_commands
-        self._single_byte_bounds = single_byte_bounds
-        self._width = width
-        self._height = height
-        self._colstart = colstart
-        self._rowstart = rowstart
-        self._rotation = rotation
-        self._auto_brightness = auto_brightness
-        self._brightness = 1.0
-        self._auto_refresh = auto_refresh
-        self._initialize(init_sequence)
-        self._buffer = Image.new("RGB", (width, height))
-        self._subrectangles = []
-        self._bounds_encoding = ">BB" if single_byte_bounds else ">HH"
-        self._current_group = None
-        displays.append(self)
-        self._refresh_thread = None
-        if self._auto_refresh:
-            self.auto_refresh = True
-        self._colorconverter = ColorConverter()
+        self._first_manual_refresh = not auto_refresh
+        self._backlight_on_high = backlight_on_high
 
-        self._backlight_type = None
-        if backlight_pin is not None:
-            try:
-                from pwmio import PWMOut  # pylint: disable=import-outside-toplevel
+        self._native_frames_per_second = native_frames_per_second
+        self._native_ms_per_frame = 1000 // native_frames_per_second
 
-                # 100Hz looks decent and doesn't keep the CPU too busy
-                self._backlight = PWMOut(backlight_pin, frequency=100, duty_cycle=0)
-                self._backlight_type = BACKLIGHT_PWM
-            except ImportError:
-                # PWMOut not implemented on this platform
-                pass
-            if self._backlight_type is None:
-                self._backlight_type = BACKLIGHT_IN_OUT
-                self._backlight = digitalio.DigitalInOut(backlight_pin)
-                self._backlight.switch_to_output()
-            self.brightness = brightness
+        self._brightness = brightness
+        self._auto_refresh = auto_refresh
 
-    def _initialize(self, init_sequence):
         i = 0
         while i < len(init_sequence):
             command = init_sequence[i]
             data_size = init_sequence[i + 1]
-            delay = (data_size & 0x80) > 0
-            data_size &= ~0x80
+            delay = (data_size & DELAY) != 0
+            data_size &= ~DELAY
+            while self._core.begin_transaction():
+                pass
 
-            if self._data_as_commands:
+            if self._core.data_as_commands:
+                full_command = bytearray(data_size + 1)
+                full_command[0] = command
+                full_command[1:] = init_sequence[i + 2 : i + 2 + data_size]
                 self._core.send(
                     DISPLAY_COMMAND,
                     CHIP_SELECT_TOGGLE_EVERY_BYTE,
-                    bytes([command]) + init_sequence[i + 2 : i + 2 + data_size],
+                    full_command,
                 )
             else:
                 self._core.send(
@@ -205,6 +189,7 @@ class Display:
                     CHIP_SELECT_UNTOUCHED,
                     init_sequence[i + 2 : i + 2 + data_size],
                 )
+            self._core.end_transaction()
             delay_time_ms = 10
             if delay:
                 data_size += 1
@@ -214,33 +199,67 @@ class Display:
             time.sleep(delay_time_ms / 1000)
             i += 2 + data_size
 
-    def _send(self, command, data):
-        self._core.begin_transaction()
-        if self._data_as_commands:
-            self._core.send(
-                DISPLAY_COMMAND, CHIP_SELECT_TOGGLE_EVERY_BYTE, bytes([command]) + data
-            )
-        else:
-            self._core.send(
-                DISPLAY_COMMAND, CHIP_SELECT_TOGGLE_EVERY_BYTE, bytes([command])
-            )
-            self._core.send(DISPLAY_DATA, CHIP_SELECT_UNTOUCHED, data)
-        self._core.end_transaction()
+        self._current_group = None
+        self._last_refresh_call = 0
+        self._refresh_thread = None
+        self._colorconverter = ColorConverter()
+
+        self._backlight_type = None
+        if backlight_pin is not None:
+            try:
+                from pwmio import PWMOut  # pylint: disable=import-outside-toplevel
+
+                # 100Hz looks decent and doesn't keep the CPU too busy
+                self._backlight = PWMOut(backlight_pin, frequency=100, duty_cycle=0)
+                self._backlight_type = BACKLIGHT_PWM
+            except ImportError:
+                # PWMOut not implemented on this platform
+                pass
+            if self._backlight_type is None:
+                self._backlight_type = BACKLIGHT_IN_OUT
+                self._backlight = digitalio.DigitalInOut(backlight_pin)
+                self._backlight.switch_to_output()
+        self.brightness = brightness
+        if not circuitpython_splash._in_group:
+            self._set_root_group(circuitpython_splash)
+        self.auto_refresh = auto_refresh
+
+    def __new__(cls, *args, **kwargs):
+        from . import (  # pylint: disable=import-outside-toplevel, cyclic-import
+            allocate_display,
+        )
 
-    def _send_pixels(self, data):
-        if not self._data_as_commands:
+        display_instance = super().__new__(cls)
+        allocate_display(display_instance)
+        return display_instance
+
+    def _send_pixels(self, pixels):
+        if not self._core.data_as_commands:
             self._core.send(
                 DISPLAY_COMMAND,
                 CHIP_SELECT_TOGGLE_EVERY_BYTE,
                 bytes([self._write_ram_command]),
             )
-        self._core.send(DISPLAY_DATA, CHIP_SELECT_UNTOUCHED, data)
+        self._core.send(DISPLAY_DATA, CHIP_SELECT_UNTOUCHED, pixels)
 
     def show(self, group: Group) -> None:
-        """Switches to displaying the given group of layers. When group is None, the
+        """
+        .. note:: `show()` is deprecated and will be removed when CircuitPython 9.0.0
+        is released. Use ``.root_group = group`` instead.
+
+        Switches to displaying the given group of layers. When group is None, the
         default CircuitPython terminal will be shown.
+
+        :param Group group: The group to show.
         """
-        self._core.show(group)
+        if group is None:
+            group = circuitpython_splash
+        self._core.set_root_group(group)
+
+    def _set_root_group(self, root_group: Group) -> None:
+        ok = self._core.set_root_group(root_group)
+        if not ok:
+            raise ValueError("Group already used")
 
     def refresh(
         self,
@@ -248,7 +267,6 @@ class Display:
         target_frames_per_second: Optional[int] = None,
         minimum_frames_per_second: int = 0,
     ) -> bool:
-        # pylint: disable=unused-argument, protected-access
         """When auto refresh is off, waits for the target frame rate and then refreshes the
         display, returning True. If the call has taken too long since the last refresh call
         for the given target frame rate, then the refresh returns False immediately without
@@ -260,122 +278,178 @@ class Display:
         When auto refresh is on, updates the display immediately. (The display will also
         update without calls to this.)
         """
-        if not self._core.start_refresh():
-            return False
+        maximum_ms_per_real_frame = 0xFFFFFFFF
+        if minimum_frames_per_second > 0:
+            maximum_ms_per_real_frame = 1000 // minimum_frames_per_second
 
-        # Go through groups and and add each to buffer
-        if self._core._current_group is not None:
-            buffer = Image.new("RGBA", (self._core._width, self._core._height))
-            # Recursively have everything draw to the image
-            self._core._current_group._fill_area(
-                buffer
-            )  # pylint: disable=protected-access
-            # save image to buffer (or probably refresh buffer so we can compare)
-            self._buffer.paste(buffer)
+        if target_frames_per_second is None:
+            target_ms_per_frame = 0xFFFFFFFF
+        else:
+            target_ms_per_frame = 1000 // target_frames_per_second
+
+        if (
+            not self._auto_refresh
+            and not self._first_manual_refresh
+            and target_ms_per_frame != 0xFFFFFFFF
+        ):
+            current_time = time.monotonic() * 1000
+            current_ms_since_real_refresh = current_time - self._core.last_refresh
+            if current_ms_since_real_refresh > maximum_ms_per_real_frame:
+                raise RuntimeError("Below minimum frame rate")
+            current_ms_since_last_call = current_time - self._last_refresh_call
+            self._last_refresh_call = current_time
+            if current_ms_since_last_call > target_ms_per_frame:
+                return False
+
+            remaining_time = target_ms_per_frame - (
+                current_ms_since_real_refresh % target_ms_per_frame
+            )
+            time.sleep(remaining_time / 1000)
+        self._first_manual_refresh = False
+        self._refresh_display()
+        return True
 
-        self._subrectangles = self._core.get_refresh_areas()
+    def _refresh_display(self):
+        if not self._core.start_refresh():
+            return False
 
-        for area in self._subrectangles:
-            self._refresh_display_area(area)
+        areas_to_refresh = self._get_refresh_areas()
+        for area in areas_to_refresh:
+            self._refresh_area(area)
 
         self._core.finish_refresh()
 
         return True
 
-    def _refresh_loop(self):
-        while self._auto_refresh:
+    def _get_refresh_areas(self) -> list[Area]:
+        """Get a list of areas to be refreshed"""
+        areas = []
+        if self._core.full_refresh:
+            areas.append(self._core.area)
+        elif self._core.current_group is not None:
+            self._core.current_group._get_refresh_areas(  # pylint: disable=protected-access
+                areas
+            )
+        return areas
+
+    def _background(self):
+        """Run background refresh tasks. Do not call directly"""
+        if (
+            self._auto_refresh
+            and (time.monotonic() * 1000 - self._core.last_refresh)
+            > self._native_ms_per_frame
+        ):
             self.refresh()
 
-    def _refresh_display_area(self, rectangle):
-        """Loop through dirty rectangles and redraw that area."""
-        img = self._buffer.convert("RGB").crop(astuple(rectangle))
-        img = img.rotate(360 - self._rotation, expand=True)
-
-        display_rectangle = self._apply_rotation(rectangle)
-        img = img.crop(astuple(self._clip(display_rectangle)))
-
-        data = numpy.array(img).astype("uint16")
-        color = (
-            ((data[:, :, 0] & 0xF8) << 8)
-            | ((data[:, :, 1] & 0xFC) << 3)
-            | (data[:, :, 2] >> 3)
-        )
-
-        pixels = bytes(
-            numpy.dstack(((color >> 8) & 0xFF, color & 0xFF)).flatten().tolist()
-        )
-
-        self._send(
-            self._set_column_command,
-            self._encode_pos(
-                display_rectangle.x1 + self._colstart,
-                display_rectangle.x2 + self._colstart - 1,
-            ),
-        )
-        self._send(
-            self._set_row_command,
-            self._encode_pos(
-                display_rectangle.y1 + self._rowstart,
-                display_rectangle.y2 + self._rowstart - 1,
-            ),
-        )
+    def _refresh_area(self, area) -> bool:
+        """Loop through dirty areas and redraw that area."""
+        # pylint: disable=too-many-locals, too-many-branches
+
+        clipped = Area()
+        # Clip the area to the display by overlapping the areas.
+        # If there is no overlap then we're done.
+        if not self._core.clip_area(area, clipped):
+            return True
+
+        rows_per_buffer = clipped.height()
+        pixels_per_word = 32 // self._core.colorspace.depth
+        pixels_per_buffer = clipped.size()
+
+        # We should have lots of memory
+        buffer_size = clipped.size() // pixels_per_word
+
+        subrectangles = 1
+        # for SH1107 and other boundary constrained controllers
+        #      write one single row at a time
+        if self._core.sh1107_addressing:
+            subrectangles = rows_per_buffer // 8
+            rows_per_buffer = 8
+        elif clipped.size() > buffer_size * pixels_per_word:
+            rows_per_buffer = buffer_size * pixels_per_word // clipped.width()
+            if rows_per_buffer == 0:
+                rows_per_buffer = 1
+            # If pixels are packed by column then ensure rows_per_buffer is on a byte boundary
+            if (
+                self._core.colorspace.depth < 8
+                and self._core.colorspace.pixels_in_byte_share_row
+            ):
+                pixels_per_byte = 8 // self._core.colorspace.depth
+                if rows_per_buffer % pixels_per_byte != 0:
+                    rows_per_buffer -= rows_per_buffer % pixels_per_byte
+            subrectangles = clipped.height() // rows_per_buffer
+            if clipped.height() % rows_per_buffer != 0:
+                subrectangles += 1
+            pixels_per_buffer = rows_per_buffer * clipped.width()
+            buffer_size = pixels_per_buffer // pixels_per_word
+            if pixels_per_buffer % pixels_per_word:
+                buffer_size += 1
+        mask_length = (pixels_per_buffer // 32) + 1  # 1 bit per pixel + 1
+        remaining_rows = clipped.height()
+
+        for subrect_index in range(subrectangles):
+            subrectangle = Area(
+                x1=clipped.x1,
+                y1=clipped.y1 + rows_per_buffer * subrect_index,
+                x2=clipped.x2,
+                y2=clipped.y1 + rows_per_buffer * (subrect_index + 1),
+            )
+            if remaining_rows < rows_per_buffer:
+                subrectangle.y2 = subrectangle.y1 + remaining_rows
+            remaining_rows -= rows_per_buffer
+            self._core.set_region_to_update(subrectangle)
+            if self._core.colorspace.depth >= 8:
+                subrectangle_size_bytes = subrectangle.size() * (
+                    self._core.colorspace.depth // 8
+                )
+            else:
+                subrectangle_size_bytes = subrectangle.size() // (
+                    8 // self._core.colorspace.depth
+                )
 
-        self._core.begin_transaction()
-        self._send_pixels(pixels)
-        self._core.end_transaction()
+            buffer = memoryview(bytearray([0] * (buffer_size * 4))).cast("I")
+            mask = memoryview(bytearray([0] * (mask_length * 4))).cast("I")
+            self._core.fill_area(subrectangle, mask, buffer)
 
-    def _clip(self, rectangle):
-        if self._rotation in (90, 270):
-            width, height = self._height, self._width
-        else:
-            width, height = self._width, self._height
-
-        rectangle.x1 = max(rectangle.x1, 0)
-        rectangle.y1 = max(rectangle.y1, 0)
-        rectangle.x2 = min(rectangle.x2, width)
-        rectangle.y2 = min(rectangle.y2, height)
-
-        return rectangle
-
-    def _apply_rotation(self, rectangle):
-        """Adjust the rectangle coordinates based on rotation"""
-        if self._rotation == 90:
-            return RectangleStruct(
-                self._height - rectangle.y2,
-                rectangle.x1,
-                self._height - rectangle.y1,
-                rectangle.x2,
-            )
-        if self._rotation == 180:
-            return RectangleStruct(
-                self._width - rectangle.x2,
-                self._height - rectangle.y2,
-                self._width - rectangle.x1,
-                self._height - rectangle.y1,
-            )
-        if self._rotation == 270:
-            return RectangleStruct(
-                rectangle.y1,
-                self._width - rectangle.x2,
-                rectangle.y2,
-                self._width - rectangle.x1,
-            )
-        return rectangle
+            # Can't acquire display bus; skip the rest of the data.
+            if not self._core.bus_free():
+                return False
 
-    def _encode_pos(self, x, y):
-        """Encode a postion into bytes."""
-        return struct.pack(self._bounds_encoding, x, y)  # pylint: disable=no-member
+            self._core.begin_transaction()
+            self._send_pixels(buffer.tobytes()[:subrectangle_size_bytes])
+            self._core.end_transaction()
+        return True
 
-    def fill_row(
-        self, y: int, buffer: circuitpython_typing.WriteableBuffer
-    ) -> circuitpython_typing.WriteableBuffer:
+    def fill_row(self, y: int, buffer: WriteableBuffer) -> WriteableBuffer:
         """Extract the pixels from a single row"""
-        for x in range(0, self._width):
-            _rgb_565 = self._colorconverter.convert(self._buffer.getpixel((x, y)))
-            buffer[x * 2] = (_rgb_565 >> 8) & 0xFF
-            buffer[x * 2 + 1] = _rgb_565 & 0xFF
+        if self._core.colorspace.depth != 16:
+            raise ValueError("Display must have a 16 bit colorspace.")
+
+        area = Area(0, y, self._core.width, y + 1)
+        pixels_per_word = 32 // self._core.colorspace.depth
+        buffer_size = self._core.width // pixels_per_word
+        pixels_per_buffer = area.size()
+        if pixels_per_buffer % pixels_per_word:
+            buffer_size += 1
+
+        buffer = memoryview(bytearray([0] * (buffer_size * 4))).cast("I")
+        mask_length = (pixels_per_buffer // 32) + 1
+        mask = memoryview(bytearray([0] * (mask_length * 4))).cast("I")
+        self._core.fill_area(area, mask, buffer)
         return buffer
 
+    def _release(self) -> None:
+        """Release the display and free its resources"""
+        self.auto_refresh = False
+        self._core.release_display_core()
+
+    def _reset(self) -> None:
+        """Reset the display"""
+        self.auto_refresh = True
+        circuitpython_splash.x = 0
+        circuitpython_splash.y = 0
+        if not circuitpython_splash._in_group:  # pylint: disable=protected-access
+            self._set_root_group(circuitpython_splash)
+
     @property
     def auto_refresh(self) -> bool:
         """True when the display is refreshed automatically."""
@@ -383,52 +457,47 @@ class Display:
 
     @auto_refresh.setter
     def auto_refresh(self, value: bool):
+        self._first_manual_refresh = not value
         self._auto_refresh = value
-        if self._refresh_thread is None:
-            self._refresh_thread = threading.Thread(
-                target=self._refresh_loop, daemon=True
-            )
-        if value and not self._refresh_thread.is_alive():
-            # Start the thread
-            self._refresh_thread.start()
-        elif not value and self._refresh_thread.is_alive():
-            # Stop the thread
-            self._refresh_thread.join()
 
     @property
     def brightness(self) -> float:
-        """The brightness of the display as a float. 0.0 is off and 1.0 is full `brightness`.
-        When `auto_brightness` is True, the value of `brightness` will change automatically.
-        If `brightness` is set, `auto_brightness` will be disabled and will be set to False.
-        """
+        """The brightness of the display as a float. 0.0 is off and 1.0 is full `brightness`."""
         return self._brightness
 
     @brightness.setter
     def brightness(self, value: float):
         if 0 <= float(value) <= 1.0:
-            self._brightness = value
-            if self._backlight_type == BACKLIGHT_IN_OUT:
-                self._backlight.value = round(self._brightness)
-            elif self._backlight_type == BACKLIGHT_PWM:
-                self._backlight.duty_cycle = self._brightness * 65535
+            if not self._backlight_on_high:
+                value = 1.0 - value
+
+            if self._backlight_type == BACKLIGHT_PWM:
+                self._backlight.duty_cycle = value * 0xFFFF
+            elif self._backlight_type == BACKLIGHT_IN_OUT:
+                self._backlight.value = value > 0.99
             elif self._brightness_command is not None:
-                self._send(self._brightness_command, round(value * 255))
+                okay = self._core.begin_transaction()
+                if okay:
+                    if self._core.data_as_commands:
+                        self._core.send(
+                            DISPLAY_COMMAND,
+                            CHIP_SELECT_TOGGLE_EVERY_BYTE,
+                            bytes([self._brightness_command, round(0xFF * value)]),
+                        )
+                    else:
+                        self._core.send(
+                            DISPLAY_COMMAND,
+                            CHIP_SELECT_TOGGLE_EVERY_BYTE,
+                            bytes([self._brightness_command]),
+                        )
+                        self._core.send(
+                            DISPLAY_DATA, CHIP_SELECT_UNTOUCHED, round(value * 255)
+                        )
+                    self._core.end_transaction()
+            self._brightness = value
         else:
             raise ValueError("Brightness must be between 0.0 and 1.0")
 
-    @property
-    def auto_brightness(self) -> bool:
-        """True when the display brightness is adjusted automatically, based on an ambient
-        light sensor or other method. Note that some displays may have this set to True by
-        default, but not actually implement automatic brightness adjustment.
-        `auto_brightness` is set to False if `brightness` is set manually.
-        """
-        return self._auto_brightness
-
-    @auto_brightness.setter
-    def auto_brightness(self, value: bool):
-        self._auto_brightness = value
-
     @property
     def width(self) -> int:
         """Display Width"""
@@ -446,9 +515,31 @@ class Display:
 
     @rotation.setter
     def rotation(self, value: int):
+        if value % 90 != 0:
+            raise ValueError("Display rotation must be in 90 degree increments")
+        transposed = self._core.rotation in (90, 270)
+        will_transposed = value in (90, 270)
+        if transposed != will_transposed:
+            self._core.width, self._core.height = self._core.height, self._core.width
         self._core.set_rotation(value)
+        if self._core.current_group is not None:
+            self._core.current_group._update_transform(  # pylint: disable=protected-access
+                self._core.transform
+            )
 
     @property
     def bus(self) -> _DisplayBus:
         """Current Display Bus"""
         return self._core.get_bus()
+
+    @property
+    def root_group(self) -> Group:
+        """The root group on the display.
+        If the root group is set to `displayio.CIRCUITPYTHON_TERMINAL`, the default
+        CircuitPython terminal will be shown.
+        If the root group is set to ``None``, no output will be shown."""
+        return self._core.current_group
+
+    @root_group.setter
+    def root_group(self, new_group: Group) -> None:
+        self._set_root_group(new_group)