Django-rendertext 0.1 is out

We're releasing the first version of rendertext, a Django app for making use of custom fonts on a web page!

It's designed to work with the built-in Django template system by providing a simple template filter you can use to render images dynamically.

The first showcase is Talent Nord. I hope to get a longer list as more people start using it. The design of Talent Nord is by Fata Morgana, house of two intelligent designers.

I think you need a pretty recent Django for the app to work. Here's the code that does the hard work:

import md5, os
import Image, ImageFont, ImageDraw, ImageColor
from django.conf import settings

def render(text, fontalias, size = 12, color = "#000", rotation = 0):
    """Construct image from text.

    Returns a tuple with the image file path, width and height. Takes
    the parameters 'fontalias', 'size' (default 12), 'color' (default
    black) as CSS hex string, and 'rotation' (default 0) which is the
    degrees to rotate the text counter-clockwise. The constructed
    image is stored in a cache under the media root in the
    RENDERTEXT_DIR set in settings.py (default is 'rendertext/').

    The font file to use is determined by mapping the fontalias
    through the RENDERTEXT_FONTMAP setting, a dictionary from
    fontalias strings to font file paths, e.g. {'verdana':
    '/home/django/fonts/verdana.ttf'}."""

    # get settings
    render_dir = "rendertext/"
    if hasattr(settings, "RENDERTEXT_DIR"):
        render_dir = settings.RENDERTEXT_DIR
    
    fontmap = settings.RENDERTEXT_FONTMAP

    fontfile = fontmap[fontalias]
    info = "|".join([text, fontalias, str(size), str(color), str(rotation)])
    name = md5.new(info.encode('utf-8')).hexdigest()
    filepath = render_dir + name + ".png"
    
    dim = (-1, -1)
    if not os.access(settings.MEDIA_ROOT + filepath, os.F_OK):
        # construct the image
        imf = ImageFont.truetype(fontfile, size)
        dim = imf.getsize(text)
        im = Image.new("RGBA", dim, ImageColor.getrgb(color) + (0,))

        draw = ImageDraw.Draw(im)
        weird_font_renderer_fix = " "
        draw.text((0, 0), text + weird_font_renderer_fix, font=imf, fill=color)

        if rotation != 0:
            im = im.rotate(rotation, Image.BICUBIC, True)
            dim = im.size

        if not os.access(settings.MEDIA_ROOT + render_dir, os.F_OK):
            os.makedirs(settings.MEDIA_ROOT + render_dir)
        
        im.save(settings.MEDIA_ROOT + filepath, "PNG")
    else:
        # read width and height
        im = Image.open(settings.MEDIA_ROOT + filepath)
        dim = im.size

    return (settings.MEDIA_URL + filepath, dim[0], dim[1])
    

def render_tag(text, *args, **kwargs):
    """Construct image tag from text."""
    (path, width, height) = render(text, *args, **kwargs)
    if not path:
        return ""
    else:
        dim = ""
        if width > 0 and height > 0:
            dim = 'width="%s" height="%s" ' % (width, height)
            
        return '<img src="%s" alt="%s" %s/>' % (path, text, dim)