terom@79: """
terom@79:     Use of PIL to render the image formatting stuff
terom@79: """
terom@79: 
terom@79: from PIL import Image, ImageDraw, ImageFont
terom@79: 
terom@79: from cStringIO import StringIO
terom@79: 
terom@79: class PILImageFormatter (object) :
terom@79:     """
terom@79:         Implements the basic image-rendering operations on top of format_txt
terom@79:     """
terom@79:     
terom@79:     # the font we load
terom@79:     font = None
terom@79: 
terom@79:     def _load_font (self) :
terom@79:         """
terom@79:             Use the configured img_ttf_path for a TrueType font, or a default one
terom@79:         """
terom@79: 
terom@79:         if self.font :
terom@79:             pass
terom@79:         
terom@79:         elif self.img_ttf_path :
terom@79:             # load truetype with configured size
terom@79:             self.font = ImageFont.truetype(self.img_ttf_path, self.img_font_size)
terom@79: 
terom@79:         else :
terom@79:             # default
terom@79:             self.font = ImageFont.load_default()
terom@79: 
terom@79:         return self.font
terom@79: 
terom@79:     def format_png (self, lines, **kwargs) :
terom@79:         # load font
terom@79:         font = self._load_font()
terom@79: 
terom@79:         # build list of plain-text line data
terom@79:         lines = list(data for line, data in self.format_txt(lines, **kwargs))
terom@79:         
terom@79:         # lines sizes
terom@79:         line_sizes = [font.getsize(line) for line in lines]
terom@79: 
terom@79:         # figure out how wide/high the image will be
terom@79:         width = max(width for width, height in line_sizes)
terom@79:         height = sum(height for width, height in line_sizes)
terom@79: 
terom@79:         # create new B/W image
terom@79:         img = Image.new('L', (width, height), 0xff)
terom@79: 
terom@79:         # drawer
terom@79:         draw = ImageDraw.Draw(img)
terom@79:         
terom@79:         # starting offset
terom@79:         offset_y = 0
terom@79: 
terom@79:         # draw the lines
terom@79:         for line, (width, height) in zip(lines, line_sizes) :
terom@79:             # draw
terom@79:             draw.text((0, offset_y), line, font=font)
terom@79: 
terom@79:             # next offset
terom@79:             offset_y += height
terom@79:         
terom@79:         # output buffer
terom@79:         buf = StringIO()
terom@79: 
terom@79:         # save
terom@79:         img.save(buf, 'png')
terom@79: 
terom@79:         # return data
terom@79:         return buf.getvalue()
terom@79: