def unwrap_transforms(svg):
'Undo global coordinate transformation, if there is one.'
groups = svg.findall('g')
if len(groups) != 1:
return False
group = groups[0]
if not set(group.attrib.keys()) <= {'id', 'transform'}:
return False
if not group.attrib.get('transform'):
return False
mat = simpletransform.parse_transform(group.attrib['transform'])
# Recognize pdf coordinate transformation
if not (almost_zero(mat[0][0] - 4/3) and
almost_zero(mat[1][1] + 4/3) and
almost_zero(mat[0][1]) and
almost_zero(mat[1][0]) and
almost_zero(mat[0][2])):
return False
mat = [[1, 0, 0], [0, -1, mat[1][2]*3/4]]
for child in group:
child_mat = simpletransform.parse_transform(
child.attrib.get('transform', ''), mat)
child.attrib['transform'] = simpletransform.format_transform(child_mat)
svg.append(child)
group.drop_tree()
simplify_transforms(svg)
return True
def simplify_transforms(svg):
'Re-format transform attributes to save characters.'
for elt in svg.xpath('//*[@transform]'):
mat = simpletransform.parse_transform(elt.attrib['transform'])
# Recognize identity / translation
if (almost_zero(mat[0][0] - 1) and
almost_zero(mat[1][1] - 1) and
almost_zero(mat[0][1]) and
almost_zero(mat[1][0])):
if almost_zero(mat[1][2]):
if almost_zero(mat[0][2]):
del elt.attrib['transform']
continue
elt.attrib['transform'] = 'translate({})'.format(
smart_round(mat[0][2]))
continue
elt.attrib['transform'] = 'translate({} {})'.format(
smart_round(mat[0][2]), smart_round(mat[1][2]))
continue
# Recognize scale
if (almost_zero(mat[0][1]) and
almost_zero(mat[0][2]) and
almost_zero(mat[1][0]) and
almost_zero(mat[1][2])):
if almost_zero(mat[0][0] - mat[1][1]):
elt.attrib['transform'] = 'scale({})'.format(
smart_round(mat[0][0]))
continue
elt.attrib['transform'] = 'scale({} {})'.format(
smart_round(mat[0][0]), smart_round(mat[1][1]))
continue
elt.attrib['transform'] = "matrix({},{},{},{},{},{})".format(
smart_round(mat[0][0]), smart_round(mat[1][0]),
smart_round(mat[0][1]), smart_round(mat[1][1]),
smart_round(mat[0][2]), smart_round(mat[1][2]))