def apply(self, dest_page: int, x: int, y: int):
"""
Apply a stamp to a particular page in the PDF writer attached to this
:class:`.TextStamp` instance.
:param dest_page:
Index of the page to which the stamp is to be applied
(starting at `0`).
:param x:
Horizontal position of the stamp's lower left corner on the page.
:param y:
Vertical position of the stamp's lower left corner on the page.
:return:
A reference to the affected page object, together with
a ``(width, height)`` tuple describing the dimensions of the stamp.
"""
stamp_ref = self.register()
resource_name = b'/Stamp' + hexlify(uuid.uuid4().bytes)
stamp_paint = b'q 1 0 0 1 %g %g cm %s Do Q' % (rd(x), rd(y),
resource_name)
stamp_wrapper_stream = generic.StreamObject(stream_data=stamp_paint)
resources = generic.DictionaryObject({
pdf_name('/XObject'):
generic.DictionaryObject(
{pdf_name(resource_name.decode('ascii')): stamp_ref})
})
wr = self.writer
page_ref = wr.add_stream_to_page(dest_page,
wr.add_object(stamp_wrapper_stream),
resources)
dims = (self.box.width, self.box.height)
return page_ref, dims
def render_command_stream(self):
# start a command stream with fill colour set to black
command_stream = ['0 0 0 rg']
for row, col in self._img:
(x, y), _ = self.pixel_box(row, col)
# paint a rectangle
command_stream.append(
'%g %g %g %g re f' %
(rd(x), rd(y), rd(self.box_size), rd(self.box_size)))
return ' '.join(command_stream).encode('ascii')
def extra_commands(self):
qr_ref, natural_qr_size = self._qr_xobject()
self.set_resource(category=ResourceType.XOBJECT,
name=pdf_name('/QR'),
value=qr_ref)
height = self.get_stamp_height()
qr_y_sep = (height - self.qr_size) // 2
qr_scale = self.qr_size / natural_qr_size
# paint the QR code, translated and with y axis inverted
draw_qr_command = b'q %g 0 0 -%g %g %g cm /QR Do Q' % (
rd(qr_scale),
rd(qr_scale),
rd(self.style.innsep),
rd(height - qr_y_sep),
)
return [draw_qr_command]
def mm2uu(mm_len):
return rd((mm_len / 25.4) * PDF_UUPI)