ReportLab: working with Chinese/Unicode characters ReportLab: working with Chinese/Unicode characters python python

ReportLab: working with Chinese/Unicode characters


This question fascinated me the complete week, so since it is weekend I dived right into it and exactly found a solution which I called MultiFontParagraph it is a normal Paragraph with one big difference you can exactly set a font fallback order.

Example of the font fallback working

For example this random Japanese text I pulled of the internet used the following font fallback "Bauhaus", "Arial", "HanaMinA". It checks whether the first font has a glyph for the character, if so it uses it, if not it fallsback to the next font. Currently the code isn't really efficient as it places tags around each character, this can easily be fixed but for clarity I didn't do it here.

Using the following code I created the above example:

foreign_string = u'6905\u897f\u963f\u79d1\u8857\uff0c\u5927\u53a6\uff03\u5927'P = MultiFontParagraph(foreign_string, styles["Normal"],                     [  ("Bauhaus", "C:\Windows\Fonts\\BAUHS93.TTF"),                        ("Arial", "C:\Windows\Fonts\\arial.ttf"),                        ("HanaMinA", 'C:\Windows\Fonts\HanaMinA.ttf')])

The source of the MultiFontParagraph (git) is as follows:

from reportlab.pdfbase import pdfmetricsfrom reportlab.pdfbase.ttfonts import TTFontfrom reportlab.platypus import Paragraphclass MultiFontParagraph(Paragraph):    # Created by B8Vrede for http://stackoverflow.com/questions/35172207/    def __init__(self, text, style, fonts_locations):        font_list = []        for font_name, font_location in fonts_locations:            # Load the font            font = TTFont(font_name, font_location)            # Get the char width of all known symbols            font_widths = font.face.charWidths            # Register the font to able it use            pdfmetrics.registerFont(font)            # Store the font and info in a list for lookup            font_list.append((font_name, font_widths))        # Set up the string to hold the new text        new_text = u''        # Loop through the string        for char in text:            # Loop through the fonts            for font_name, font_widths in font_list:                # Check whether this font know the width of the character                # If so it has a Glyph for it so use it                if ord(char) in font_widths:                    # Set the working font for the current character                    new_text += u'<font name="{}">{}</font>'.format(font_name, char)                    break        Paragraph.__init__(self, new_text, style)


From Google Noto Fonts:

Google has been developing a font family called Noto, which aims to support all languages with a harmonious look and feel.

The unified Noto Sans font includes a single font, supporting 581 languages from the following areas:

enter image description here

Others such as Hebrew, Arabic and Japanese are listed as separate items on the Noto website.