MicroPython Forum (Archive)

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def draw_image(f,x,y):
    print("need to read the header and then blit to the screen")
    print(f, x, y)

# static helper to store/cache the fonts
class Fonts:

    _segoe14 = None
    _segoe16 = None
    _segoe24 = None
    _segoe36 = None

    @staticmethod
    def Segoe14():
        if Fonts._segoe14 is None:
            Fonts._segoe14 = Font('segoe-14.gff')
        return Fonts._segoe14

    @staticmethod
    def Segoe16():
        if Fonts._segoe16 is None:
            Fonts._segoe16 = Font('segoe-16.gff')
        return Fonts._segoe16

    @staticmethod
    def Segoe24():
        if Fonts._segoe24 is None:
            Fonts._segoe24 = Font('segoe-24.gff')
        return Fonts._segoe24

    @staticmethod
    def Segoe36():
        if Fonts._segoe36 is None:
            Fonts._segoe36 = Font('segoe-36.gff')
        return Fonts._segoe36

    @staticmethod
    def Load():
        # preload fonts we want to avoid delays - can take some time
        Fonts.Segoe14()
        Fonts.Segoe16()
        Fonts.Segoe24()
        Fonts.Segoe36()


class Font(object):

    def __init__(self, filename):
        # save the filename for multiple use
        self._filename = filename
        # open read glpyh info and close
        with open(filename, 'rb') as f:
            # generate lookup table - takes a little while
            self.table = {}
            index = 0
            for c in range(32, 127):
                r = f.seek(index)
                header = f.read(4)
                w = header[0]*256 + header[1]
                h = header[2]*256 + header[3]
                self.table[chr(c)] = (w,h,index)
                index += 6 + w * h * 2
        # save some meta data about this font
        self.emwidth, self.font_height = self.measure('M')
        self.line_height = self.font_height + 1  ## ??
        self.f = None

    def open(self):
        self.f = open(self._filename, 'rb')
        return self

    def release(self):
        if self.f:
            self.f.close()
            #del self.f
            self.f = None

    def __enter__(self):
        return self.open()

    def __exit__(self, type, value, traceback):
        self.release()

    def draw_text(self, x, y, text, align='left'):
        # check self.f is not None
        if not self.f:
            raise ValueError('draw_text not called in an open context')
        if align == 'center':
            w, h = self.measure(text)
            x -= w // 2
        elif align == 'right':
            w, h = self.measure(text)
            x -= w
        elif align != 'left':
            raise ValueError("align should be 'left', 'center' or 'right'")
        for c in text:
            w, h, index = self.table[c]
            self.f.seek(index)
            r = draw_image(self.f, x, y)
            x += w
        pass

    # doesnt require the file to be open to do this
    def measure(self, text):
        width, height = 0, 0
        for c in text:
            w, h, index = self.table[c]
            width += w
            height = max(height, h)
        return width, height

    def __del__(self):
        self.release()

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new pixel = min(limit, old + weight * color)