apps/picture/templatetags/picture_tags.py

   1 from django import template
   2 from django.template import Node, Variable, Template, Context
   3 from catalogue.utils import split_tags
   4 from itertools import chain
   5 from ..engine import CustomCroppingEngine
   6 import sorl.thumbnail.default
   7 import logging
   8
   9 register = template.Library()
  10
  11 cropper = CustomCroppingEngine()
  12
  13 @register.inclusion_tag('picture/picture_short.html', takes_context=True)
  14 def picture_short(context, picture):
  15     context.update({
  16         'picture': picture,
  17         'main_link': picture.get_absolute_url(),
  18         # 'related': picture.related_info(),
  19         'request': context.get('request'),
  20         'tags': split_tags(picture.tags),
  21         })
  22     return context
  23
  24 @register.inclusion_tag('picture/picture_wide.html', takes_context=True)
  25 def picture_wide(context, picture):
  26     context.update({
  27         'picture': picture,
  28         'main_link': picture.get_absolute_url(),
  29         # 'related': picture.related_info(),
  30         'request': context.get('request'),
  31         'tags': split_tags(picture.tags),
  32         })
  33     return context
  34
  35
  36 @register.simple_tag()
  37 def area_thumbnail_url(area, geometry):
  38     def to_square(coords):
  39         w = coords[1][0] - coords[0][0]
  40         h = coords[1][1] - coords[0][1]
  41         if w == h:
  42             return coords
  43         elif w > h:
  44             return [[coords[0][0] + w/2 - h/2, coords[0][1]],
  45                     [coords[1][0] - w/2 + h/2, coords[1][1]]]
  46         else:
  47             return [[coords[0][0], coords[0][1] + h/2 - w/2],
  48                     [coords[1][0], coords[1][1] - h/2 + w/2, ]]
  49
  50     # so much for sorl extensibility.                                                                                                                           # what to do about this?
  51     _engine = sorl.thumbnail.default.engine
  52     sorl.thumbnail.default.engine = cropper
  53     coords = to_square(area.area)
  54
  55     try:
  56         th = sorl.thumbnail.default.backend.get_thumbnail(
  57             area.picture.image_file,
  58             geometry,
  59             crop="%dpx %dpx %dpx %dpx" % tuple(map(lambda d: max(0, d), tuple(coords[0] + coords[1]))))
  60     except Exception, e:
  61         logging.exception("Error creating a thumbnail for PictureArea")
  62         return ''
  63
  64     sorl.thumbnail.default.engine = _engine
  65
  66     return th.url
  67
  68
  69
  70