Display module for microbit library

src/microbit/model/constants.py

@@ -95,6 +95,14 @@
     ],
 }
 
+# 5x5 Alphabet
+# Taken from https://github.com/raw/micropython/micropython/264d80c84e034541bd6e4b461bfece4443ffd0ac/ports/nrf/boards/microbit/modules/microbitfont.h
+ALPHABET = b"\x00\x00\x00\x00\x00\x08\x08\x08\x00\x08\x0a\x4a\x40\x00\x00\x0a\x5f\xea\x5f\xea\x0e\xd9\x2e\xd3\x6e\x19\x32\x44\x89\x33\x0c\x92\x4c\x92\x4d\x08\x08\x00\x00\x00\x04\x88\x08\x08\x04\x08\x04\x84\x84\x88\x00\x0a\x44\x8a\x40\x00\x04\x8e\xc4\x80\x00\x00\x00\x04\x88\x00\x00\x0e\xc0\x00\x00\x00\x00\x08\x00\x01\x22\x44\x88\x10\x0c\x92\x52\x52\x4c\x04\x8c\x84\x84\x8e\x1c\x82\x4c\x90\x1e\x1e\xc2\x44\x92\x4c\x06\xca\x52\x5f\xe2\x1f\xf0\x1e\xc1\x3e\x02\x44\x8e\xd1\x2e\x1f\xe2\x44\x88\x10\x0e\xd1\x2e\xd1\x2e\x0e\xd1\x2e\xc4\x88\x00\x08\x00\x08\x00\x00\x04\x80\x04\x88\x02\x44\x88\x04\x82\x00\x0e\xc0\x0e\xc0\x08\x04\x82\x44\x88\x0e\xd1\x26\xc0\x04\x0e\xd1\x35\xb3\x6c\x0c\x92\x5e\xd2\x52\x1c\x92\x5c\x92\x5c\x0e\xd0\x10\x10\x0e\x1c\x92\x52\x52\x5c\x1e\xd0\x1c\x90\x1e\x1e\xd0\x1c\x90\x10\x0e\xd0\x13\x71\x2e\x12\x52\x5e\xd2\x52\x1c\x88\x08\x08\x1c\x1f\xe2\x42\x52\x4c\x12\x54\x98\x14\x92\x10\x10\x10\x10\x1e\x11\x3b\x75\xb1\x31\x11\x39\x35\xb3\x71\x0c\x92\x52\x52\x4c\x1c\x92\x5c\x90\x10\x0c\x92\x52\x4c\x86\x1c\x92\x5c\x92\x51\x0e\xd0\x0c\x82\x5c\x1f\xe4\x84\x84\x84\x12\x52\x52\x52\x4c\x11\x31\x31\x2a\x44\x11\x31\x35\xbb\x71\x12\x52\x4c\x92\x52\x11\x2a\x44\x84\x84\x1e\xc4\x88\x10\x1e\x0e\xc8\x08\x08\x0e\x10\x08\x04\x82\x41\x0e\xc2\x42\x42\x4e\x04\x8a\x40\x00\x00\x00\x00\x00\x00\x1f\x08\x04\x80\x00\x00\x00\x0e\xd2\x52\x4f\x10\x10\x1c\x92\x5c\x00\x0e\xd0\x10\x0e\x02\x42\x4e\xd2\x4e\x0c\x92\x5c\x90\x0e\x06\xc8\x1c\x88\x08\x0e\xd2\x4e\xc2\x4c\x10\x10\x1c\x92\x52\x08\x00\x08\x08\x08\x02\x40\x02\x42\x4c\x10\x14\x98\x14\x92\x08\x08\x08\x08\x06\x00\x1b\x75\xb1\x31\x00\x1c\x92\x52\x52\x00\x0c\x92\x52\x4c\x00\x1c\x92\x5c\x90\x00\x0e\xd2\x4e\xc2\x00\x0e\xd0\x10\x10\x00\x06\xc8\x04\x98\x08\x08\x0e\xc8\x07\x00\x12\x52\x52\x4f\x00\x11\x31\x2a\x44\x00\x11\x31\x35\xbb\x00\x12\x4c\x8c\x92\x00\x11\x2a\x44\x98\x00\x1e\xc4\x88\x1e\x06\xc4\x8c\x84\x86\x08\x08\x08\x08\x08\x18\x08\x0c\x88\x18\x00\x00\x0c\x83\x60"
+# We support ASCII characters between these indexes on the microbit
+ASCII_START = 32
+ASCII_END = 126
+SPACE_BETWEEN_LETTERS_WIDTH = 1
+WHITESPACE_WIDTH = 3
 
 # numerical LED values
 LED_HEIGHT = 5

src/microbit/model/display.py

@@ -0,0 +1,269 @@
+import copy
+import time
+import threading
+
+from . import constants as CONSTANTS
+from .image import Image
+from .. import shim
+
+
+class Display:
+    # The implementation based off of https://github.com/bbcmicrobit/micropython/blob/master/docs/display.rst.
+
+    def __init__(self):
+        self.__image = Image()
+        self.__on = True
+        self.__current_pid = None
+        self.__blank_image = Image()
+
+        self.__lock = threading.Lock()
+
+    def scroll(self, value, delay=150, wait=True, loop=False, monospace=False):
+        if not wait:
+            thread = threading.Thread(
+                target=self.scroll, args=(value, delay, True, loop, monospace)
+            )
+            thread.start()
+            return
+
+        # Set current_pid to the thread's identifier
+        self.__lock.acquire()
+        self.__current_pid = threading.get_ident()
+        self.__lock.release()
+
+        if isinstance(value, (str, int, float)):
+            value = str(value)
+        else:
+            raise TypeError(f"can't convert {type(value)} object to str implicitly")
+
+        letters = []
+        for c in value:
+            if monospace:
+                letters.append(Display.__get_image_from_char(c))
+                letters.append(
+                    Image(CONSTANTS.SPACE_BETWEEN_LETTERS_WIDTH, CONSTANTS.LED_HEIGHT)
+                )
+            else:
+                if c == " ":
+                    letters.append(
+                        Image(CONSTANTS.WHITESPACE_WIDTH, CONSTANTS.LED_HEIGHT)
+                    )
+                else:
+                    letters.append(
+                        Display.__strip_unlit_columns(Display.__get_image_from_char(c))
+                    )
+                    letters.append(
+                        Image(
+                            CONSTANTS.SPACE_BETWEEN_LETTERS_WIDTH, CONSTANTS.LED_HEIGHT,
+                        )
+                    )
+        appended_image = Display.__create_scroll_image(letters)
+
+        while True:
+            # Show the scrolled image one square at a time.
+            for x in range(appended_image.width() - CONSTANTS.LED_WIDTH + 1):
+                self.__lock.acquire()
+
+                # If show or scroll is called again, there will be a different pid and break
+                if self.__current_pid != threading.get_ident():
+                    self.__lock.release()
+                    break
+
+                self.__image.blit(
+                    appended_image, x, 0, CONSTANTS.LED_WIDTH, CONSTANTS.LED_HEIGHT
+                )
+                self.__lock.release()
+
+                Display.sleep_ms(delay)
+
+            if not loop:
+                break
+
+    def show(self, value, delay=400, wait=True, loop=False, clear=False):
+        if not wait:
+            thread = threading.Thread(
+                target=self.show, args=(value, delay, True, loop, clear)
+            )
+            thread.start()
+            return
+
+        # Set current_pid to the thread's identifier
+        self.__lock.acquire()
+        self.__current_pid = threading.get_ident()
+        self.__lock.release()
+
+        images = []
+        use_delay = False
+        if isinstance(value, Image):
+            images.append(value.crop(0, 0, CONSTANTS.LED_WIDTH, CONSTANTS.LED_HEIGHT))
+        elif isinstance(value, (str, int, float)):
+            chars = list(str(value))
+            for c in chars:
+                images.append(Display.__get_image_from_char(c))
+            if len(chars) > 1:
+                use_delay = True
+        else:
+            # Check if iterable
+            try:
+                _ = iter(value)
+            except TypeError as e:
+                raise e
+
+            for elem in value:
+                if isinstance(elem, Image):
+                    images.append(
+                        elem.crop(0, 0, CONSTANTS.LED_WIDTH, CONSTANTS.LED_HEIGHT)
+                    )
+                elif isinstance(elem, str) and len(elem) == 1:
+                    images.append(Display.__get_image_from_char(elem))
+                # If elem is not char or image, break without iterating through rest of list
+                else:
+                    break
+            use_delay = True
+
+        while True:
+            for image in images:
+                self.__lock.acquire()
+
+                # If show or scroll is called again, there will be a different pid and break
+                if self.__current_pid != threading.get_ident():
+                    self.__lock.release()
+                    break
+
+                self.__image = image
+                self.__lock.release()
+
+                if use_delay:
+                    Display.sleep_ms(delay)
+
+            if not loop:
+                break
+        if clear:
+            self.clear()
+
+    def get_pixel(self, x, y):
+        self.__lock.acquire()
+        pixel = self.__image.get_pixel(x, y)
+        self.__lock.release()
+        return pixel
+
+    def set_pixel(self, x, y, value):
+        self.__lock.acquire()
+        self.__image.set_pixel(x, y, value)
+        self.__lock.release()
+
+    def clear(self):
+        self.__lock.acquire()
+        self.__image = Image()
+        self.__lock.release()
+
+    def on(self):
+        self.__on = True
+
+    def off(self):
+        self.__on = False
+
+    def is_on(self):
+        return self.__on
+
+    def read_light_level(self):
+        raise NotImplementedError(CONSTANTS.NOT_IMPLEMENTED_ERROR)
+
+    # Helpers
+
+    def __get_array(self):
+        if self.is_on():
+            self.__lock.acquire()
+            leds = copy.deepcopy(self.__image._Image__LED)
+            self.__lock.release()
+            return leds
+        else:
+            return self.__blank_image._Image__LED
+
+    @staticmethod
+    def __get_image_from_char(c):
+        # If c is not between the ASCII alphabet we cover, make it a question mark
+        if ord(c) < CONSTANTS.ASCII_START or ord(c) > CONSTANTS.ASCII_END:
+            c = "?"
+        offset = (ord(c) - CONSTANTS.ASCII_START) * CONSTANTS.LED_WIDTH
+        representative_bytes = CONSTANTS.ALPHABET[
+            offset : offset + CONSTANTS.LED_HEIGHT
+        ]
+        return Image(Display.__convert_bytearray_to_image_str(representative_bytes))
+
+    # Removes columns that are not lit
+    @staticmethod
+    def __strip_unlit_columns(image):
+        min_index = CONSTANTS.LED_WIDTH - 1
+        max_index = 0
+        for row in image._Image__LED:
+            for index, bit in enumerate(row):
+                if bit > 0:
+                    min_index = min(min_index, index)
+                    max_index = max(max_index, index)
+        return image.crop(min_index, 0, max_index - min_index + 1, CONSTANTS.LED_HEIGHT)
+
+    # This method is different from Image's __bytes_to_array.
+    # This one requires a conversion from binary of the ALPHABET constant to an image.
+    @staticmethod
+    def __convert_bytearray_to_image_str(byte_array):
+        arr = []
+        for b in byte_array:
+            # Convert byte to binary
+            b_as_bits = str(bin(b))[2:]
+            sub_arr = []
+            while len(sub_arr) < 5:
+                # Iterate throught bits
+                # If there is a 1 at b, then the pixel at column b is lit
+                for bit in b_as_bits[::-1]:
+                    if len(sub_arr) < 5:
+                        sub_arr.insert(0, int(bit) * CONSTANTS.BRIGHTNESS_MAX)
+                    else:
+                        break
+                # Add 0s to the front until the list is 5 long
+                while len(sub_arr) < 5:
+                    sub_arr.insert(0, 0)
+            arr.append(sub_arr)
+        image_str = ""
+        for row in arr:
+            for elem in row:
+                image_str += str(elem)
+            image_str += ":"
+        return image_str
+
+    @staticmethod
+    def __insert_blank_column(image):
+        for row in image._Image__LED:
+            row.append(0)
+
+    @staticmethod
+    def __create_scroll_image(images):
+        blank_5x5_image = Image()
+        front_of_scroll_image = Image(4, 5)
+        images.insert(0, front_of_scroll_image)
+
+        scroll_image = Image._Image__append_images(images)
+        end_of_scroll_image = Image()
+        # Insert columns of 0s until the ending is a 5x5 blank
+        end_of_scroll_image.blit(
+            scroll_image,
+            scroll_image.width() - CONSTANTS.LED_WIDTH,
+            0,
+            CONSTANTS.LED_WIDTH,
+            CONSTANTS.LED_HEIGHT,
+        )
+        while not Image._Image__same_image(end_of_scroll_image, blank_5x5_image):
+            Display.__insert_blank_column(scroll_image)
+            end_of_scroll_image.blit(
+                scroll_image,
+                scroll_image.width() - CONSTANTS.LED_WIDTH,
+                0,
+                CONSTANTS.LED_WIDTH,
+                CONSTANTS.LED_HEIGHT,
+            )
+
+        return scroll_image
+
+    @staticmethod
+    def sleep_ms(ms):
+        time.sleep(ms / 1000)

src/microbit/model/image.py

@@ -216,6 +216,24 @@ def __mul__(self, other):
 
         return res
 
+    def __repr__(self):
+        ret_str = "Image('"
+        for index_y in range(self.height()):
+            ret_str += self.__row_to_str(index_y)
+
+        ret_str += "')"
+
+        return ret_str
+
+    def __str__(self):
+        ret_str = "Image('\n"
+        for index_y in range(self.height()):
+            ret_str += "\t" + self.__row_to_str(index_y) + "\n"
+
+        ret_str += "')"
+
+        return ret_str
+
     # HELPER FUNCTIONS
 
     # This create 2D array of off LEDs with
@@ -338,23 +356,29 @@ def __row_to_str(self, y):
 
         return new_str
 
-    def __repr__(self):
-        ret_str = "Image('"
-        for index_y in range(self.height()):
-            ret_str += self.__row_to_str(index_y)
-
-        ret_str += "')"
-
-        return ret_str
-
-    def __str__(self):
-        ret_str = "Image('\n"
-        for index_y in range(self.height()):
-            ret_str += "\t" + self.__row_to_str(index_y) + "\n"
-
-        ret_str += "')"
+    @staticmethod
+    def __append_images(images):
+        width = 0
+        height = 0
+        for image in images:
+            width += image.width()
+            height = max(height, image.height())
+        res = Image(width, height)
+        x_ind = 0
+        for image in images:
+            res.blit(image, 0, 0, image.width(), image.height(), xdest=x_ind)
+            x_ind += image.width()
+        return res
 
-        return ret_str
+    @staticmethod
+    def __same_image(i1, i2):
+        if i1.width() != i2.width() or i1.height() != i2.height():
+            return False
+        for y in range(i1.height()):
+            for x in range(i1.width()):
+                if i1.get_pixel(x, y) != i2.get_pixel(x, y):
+                    return False
+        return True
 
 
 # This is for generating functions like Image.HEART

src/microbit/model/microbit_model.py

@@ -1,6 +1,7 @@
 import time
 
 from .button import Button
+from .display import Display
 
 
 class MicrobitModel:
@@ -9,6 +10,7 @@ def __init__(self):
         self.button_a = Button()
         self.button_b = Button()
         self.__start_time = time.time()
+        self.display = Display()
 
     def sleep(self, n):
         time.sleep(n / 1000)