demo_bouncing_text.py

"""SSD1322 demo (bouncing text)."""
from machine import Pin, SPI  # type: ignore
from utime import sleep_us, ticks_us, ticks_diff  # type: ignore
from ssd1322 import Display
from xglcd_font import XglcdFont


class BouncingText(object):
    """Bouncing Text."""

    def __init__(self, text, font, screen_width, screen_height,
                 speed, display, gs=15):
        """Initialize text.
        Args:
            text (string): Message to display
            font (FrameBuffer): xglcd font
            screen_width (int): Width of screen
            screen_height (int): Width of height
            speed(int): Initial XY-Speed of sprite
            display (SSD1351): OLED display object
            gs (int): Grayscale 0 - 15
        """
        self.text = text
        self.font = font
        self.w = font.measure_text(text)
        self.h = font.height
        self.screen_width = screen_width
        self.screen_height = screen_height
        self.display = display
        self.gs = gs
        self.x_speed = speed
        self.y_speed = speed
        self.x = 0
        self.y = 0
        self.prev_x = self.x
        self.prev_y = self.y

    def update_pos(self):
        """Update sprite speed and position."""
        x = self.x
        y = self.y
        w = self.w
        h = self.h
        x_speed = abs(self.x_speed)
        y_speed = abs(self.y_speed)

        if x + w + x_speed >= self.screen_width:
            self.x_speed = -x_speed
        elif x - x_speed < 0:
            self.x_speed = x_speed

        if y + h + y_speed >= self.screen_height:
            self.y_speed = -y_speed
        elif y - y_speed <= 0:
            self.y_speed = y_speed

        self.prev_x = x
        self.prev_y = y

        self.x = x + self.x_speed
        self.y = y + self.y_speed

    def draw(self):
        """Draw text."""
        x = self.x
        y = self.y
        prev_x = self.prev_x
        prev_y = self.prev_y
        w = self.w
        h = self.h
        x_speed = abs(self.x_speed)
        y_speed = abs(self.y_speed)

        # Determine direction and remove previous portion of sprite
        if prev_x > x:
            # Left
            self.display.fill_rectangle(x + w, prev_y, x_speed, h, gs=0)
        elif prev_x < x:
            # Right
            self.display.fill_rectangle(x - x_speed, prev_y, x_speed, h, gs=0)
        if prev_y > y:
            # Upward
            self.display.fill_rectangle(prev_x, y + h, w, y_speed, gs=0)
        elif prev_y < y:
            # Downward
            self.display.fill_rectangle(prev_x, y - y_speed, w, y_speed, gs=0)

        self.display.draw_text(x, y, self.text, self.font, gs=self.gs)
        self.display.present()


def test():
    """Bouncing sprite."""
    try:
        spi = SPI(0, baudrate=25000000, sck=Pin(18), mosi=Pin(19))
        display = Display(spi, dc=Pin(20), cs=Pin(17), rst=Pin(21))
        display.clear()

        unispace = XglcdFont('fonts/Unispace12x24.c', 12, 24)
        # Load text object
        bouncing_text = BouncingText('256x64 OLED Display',
                                     unispace, 256, 64, 1, display)

        while True:
            timer = ticks_us()
            bouncing_text.update_pos()
            bouncing_text.draw()
            # Attempt to set framerate to 30 FPS
            timer_dif = 33333 - ticks_diff(ticks_us(), timer)
            if timer_dif > 0:
                sleep_us(timer_dif)

    except KeyboardInterrupt:
        display.cleanup()


test()