2012-03-22 02:19:27 +04:00
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"""
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weasyprint.images
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-----------------
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2011-12-08 19:31:03 +04:00
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2012-03-22 02:19:27 +04:00
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Fetch and decode images in various formats.
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2011-12-08 19:31:03 +04:00
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"""
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2017-03-25 02:33:36 +03:00
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import math
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2012-02-17 21:49:58 +04:00
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from io import BytesIO
|
2016-02-26 15:58:47 +03:00
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from xml.etree import ElementTree
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2011-12-08 19:31:03 +04:00
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2013-02-26 18:04:52 +04:00
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import cairocffi
|
2013-02-25 19:26:39 +04:00
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import cairosvg.parser
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import cairosvg.surface
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2020-06-22 17:05:14 +03:00
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from PIL import Image
|
2016-01-15 15:15:02 +03:00
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2019-06-02 19:06:25 +03:00
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from .layout.percentages import percentage
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2017-03-25 02:33:36 +03:00
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from .logger import LOGGER
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from .urls import URLFetchingError, fetch
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2013-02-25 19:26:39 +04:00
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2012-12-30 01:59:13 +04:00
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try:
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2013-02-26 18:04:52 +04:00
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from cairocffi import pixbuf
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2012-12-30 01:59:13 +04:00
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except OSError:
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2013-02-26 18:04:52 +04:00
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pixbuf = None
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2012-12-29 17:20:38 +04:00
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2016-01-15 15:15:02 +03:00
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assert cairosvg.surface.cairo is cairocffi, (
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'CairoSVG is using pycairo instead of cairocffi. '
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'Make sure it is not imported before WeasyPrint.')
|
2012-12-29 14:50:11 +04:00
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|
2013-04-03 18:00:31 +04:00
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# Map values of the image-rendering property to cairo FILTER values:
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# Values are normalized to lower case.
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2016-08-24 18:44:21 +03:00
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IMAGE_RENDERING_TO_FILTER = {
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'auto': cairocffi.FILTER_BILINEAR,
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'crisp-edges': cairocffi.FILTER_BEST,
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'pixelated': cairocffi.FILTER_NEAREST,
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}
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2013-04-03 18:00:31 +04:00
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2013-06-21 00:32:28 +04:00
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class ImageLoadingError(ValueError):
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"""An error occured when loading an image.
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The image data is probably corrupted or in an invalid format.
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"""
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@classmethod
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def from_exception(cls, exception):
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name = type(exception).__name__
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value = str(exception)
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return cls('%s: %s' % (name, value) if value else name)
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|
2020-01-02 14:06:58 +03:00
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class RasterImage:
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2013-04-03 15:34:14 +04:00
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def __init__(self, image_surface):
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self.image_surface = image_surface
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2013-07-26 19:26:30 +04:00
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self._intrinsic_width = image_surface.get_width()
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self._intrinsic_height = image_surface.get_height()
|
2013-04-03 20:15:32 +04:00
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self.intrinsic_ratio = (
|
2013-07-26 19:26:30 +04:00
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self._intrinsic_width / self._intrinsic_height
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if self._intrinsic_height != 0 else float('inf'))
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|
2016-02-26 15:58:47 +03:00
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def get_intrinsic_size(self, image_resolution, _font_size):
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2013-07-26 19:26:30 +04:00
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# Raster images are affected by the 'image-resolution' property.
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return (self._intrinsic_width / image_resolution,
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self._intrinsic_height / image_resolution)
|
2013-04-03 15:34:14 +04:00
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|
2013-04-03 18:00:31 +04:00
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def draw(self, context, concrete_width, concrete_height, image_rendering):
|
2019-06-01 02:32:13 +03:00
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has_size = (
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concrete_width > 0
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and concrete_height > 0
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and self._intrinsic_width > 0
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and self._intrinsic_height > 0
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)
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if not has_size:
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return
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# Use the real intrinsic size here,
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# not affected by 'image-resolution'.
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context.scale(concrete_width / self._intrinsic_width,
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concrete_height / self._intrinsic_height)
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context.set_source_surface(self.image_surface)
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context.get_source().set_filter(
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IMAGE_RENDERING_TO_FILTER[image_rendering])
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context.paint()
|
2011-12-08 19:31:03 +04:00
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2013-02-25 19:26:39 +04:00
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class ScaledSVGSurface(cairosvg.surface.SVGSurface):
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"""
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Have the cairo Surface object have intrinsic dimension
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in pixels instead of points.
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"""
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@property
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def device_units_per_user_units(self):
|
2019-12-23 17:34:49 +03:00
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scale = super().device_units_per_user_units
|
2013-02-25 19:26:39 +04:00
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return scale / 0.75
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|
2020-01-02 14:06:58 +03:00
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class FakeSurface:
|
2016-02-26 15:58:47 +03:00
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"""Fake CairoSVG surface used to get SVG attributes."""
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context_height = 0
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context_width = 0
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font_size = 12
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dpi = 96
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|
2020-01-02 14:06:58 +03:00
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class SVGImage:
|
2017-06-07 12:37:53 +03:00
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|
def __init__(self, svg_data, base_url, url_fetcher):
|
2012-02-21 15:59:06 +04:00
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|
# Don’t pass data URIs to CairoSVG.
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|
# They are useless for relative URIs anyway.
|
2013-04-03 15:34:14 +04:00
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|
self._base_url = (
|
2013-04-04 21:48:23 +04:00
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|
|
base_url if not base_url.lower().startswith('data:') else None)
|
2013-04-03 15:34:14 +04:00
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|
self._svg_data = svg_data
|
2017-06-07 12:37:53 +03:00
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|
self._url_fetcher = url_fetcher
|
2013-04-03 15:34:14 +04:00
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|
2013-06-21 00:32:28 +04:00
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|
try:
|
2016-02-26 15:58:47 +03:00
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|
self._tree = ElementTree.fromstring(self._svg_data)
|
2013-06-21 00:32:28 +04:00
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|
except Exception as e:
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|
raise ImageLoadingError.from_exception(e)
|
2016-02-26 15:58:47 +03:00
|
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|
2017-06-23 13:23:22 +03:00
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def _cairosvg_url_fetcher(self, src, mimetype):
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|
data = self._url_fetcher(src)
|
2017-11-11 16:21:16 +03:00
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|
if 'string' in data:
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|
return data['string']
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|
return data['file_obj'].read()
|
2017-06-23 13:23:22 +03:00
|
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|
2016-02-26 15:58:47 +03:00
|
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def get_intrinsic_size(self, _image_resolution, font_size):
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|
# Vector images may be affected by the font size.
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|
fake_surface = FakeSurface()
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fake_surface.font_size = font_size
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# Percentages don't provide an intrinsic size, we transform percentages
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# into 0 using a (0, 0) context size:
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# http://www.w3.org/TR/SVG/coords.html#IntrinsicSizing
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self._width = cairosvg.surface.size(
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fake_surface, self._tree.get('width'))
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|
self._height = cairosvg.surface.size(
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fake_surface, self._tree.get('height'))
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|
_, _, viewbox = cairosvg.surface.node_format(fake_surface, self._tree)
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|
self._intrinsic_width = self._width or None
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|
self._intrinsic_height = self._height or None
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|
self.intrinsic_ratio = None
|
|
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|
|
if viewbox:
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|
|
|
if self._width and self._height:
|
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|
self.intrinsic_ratio = self._width / self._height
|
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|
else:
|
2016-02-26 17:28:43 +03:00
|
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|
|
if viewbox[2] and viewbox[3]:
|
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|
self.intrinsic_ratio = viewbox[2] / viewbox[3]
|
|
|
|
|
if self._width:
|
|
|
|
|
self._intrinsic_height = (
|
|
|
|
|
self._width / self.intrinsic_ratio)
|
|
|
|
|
elif self._height:
|
|
|
|
|
self._intrinsic_width = (
|
|
|
|
|
self._height * self.intrinsic_ratio)
|
2016-02-26 15:58:47 +03:00
|
|
|
|
elif self._width and self._height:
|
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|
|
|
self.intrinsic_ratio = self._width / self._height
|
2013-07-26 19:26:30 +04:00
|
|
|
|
return self._intrinsic_width, self._intrinsic_height
|
2013-04-03 15:34:14 +04:00
|
|
|
|
|
2013-04-04 21:48:23 +04:00
|
|
|
|
def draw(self, context, concrete_width, concrete_height, _image_rendering):
|
2016-02-26 17:29:05 +03:00
|
|
|
|
try:
|
|
|
|
|
svg = ScaledSVGSurface(
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|
|
|
|
cairosvg.parser.Tree(
|
2017-06-07 12:37:53 +03:00
|
|
|
|
bytestring=self._svg_data, url=self._base_url,
|
2017-06-23 13:23:22 +03:00
|
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|
|
url_fetcher=self._cairosvg_url_fetcher),
|
2019-05-20 13:28:35 +03:00
|
|
|
|
output=None, dpi=96, output_width=concrete_width,
|
|
|
|
|
output_height=concrete_height)
|
2016-02-26 17:29:05 +03:00
|
|
|
|
if svg.width and svg.height:
|
|
|
|
|
context.scale(
|
|
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|
|
concrete_width / svg.width, concrete_height / svg.height)
|
|
|
|
|
context.set_source_surface(svg.cairo)
|
|
|
|
|
context.paint()
|
|
|
|
|
except Exception as e:
|
2017-07-25 14:59:56 +03:00
|
|
|
|
LOGGER.error(
|
2016-02-26 17:29:05 +03:00
|
|
|
|
'Failed to draw an SVG image at %s : %s', self._base_url, e)
|
2012-01-12 22:26:27 +04:00
|
|
|
|
|
|
|
|
|
|
2020-06-22 17:05:14 +03:00
|
|
|
|
def get_image_from_uri(cache, url_fetcher, optimize_images, url,
|
|
|
|
|
forced_mime_type=None):
|
2013-02-26 18:04:52 +04:00
|
|
|
|
"""Get a cairo Pattern from an image URI."""
|
2013-06-20 15:58:24 +04:00
|
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|
|
missing = object()
|
2013-06-21 00:32:28 +04:00
|
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|
|
image = cache.get(url, missing)
|
2013-06-20 15:58:24 +04:00
|
|
|
|
if image is not missing:
|
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|
|
|
return image
|
|
|
|
|
|
2011-12-08 19:31:03 +04:00
|
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|
|
try:
|
2013-06-21 00:32:28 +04:00
|
|
|
|
with fetch(url_fetcher, url) as result:
|
2016-08-26 15:34:28 +03:00
|
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|
|
if 'string' in result:
|
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|
|
|
string = result['string']
|
|
|
|
|
else:
|
|
|
|
|
string = result['file_obj'].read()
|
2013-06-20 15:58:24 +04:00
|
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|
|
mime_type = forced_mime_type or result['mime_type']
|
2013-04-03 15:34:14 +04:00
|
|
|
|
if mime_type == 'image/svg+xml':
|
2016-08-26 15:34:28 +03:00
|
|
|
|
# No fallback for XML-based mimetypes as defined by MIME
|
|
|
|
|
# Sniffing Standard, see https://mimesniff.spec.whatwg.org/
|
2017-06-07 12:37:53 +03:00
|
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|
|
image = SVGImage(string, url, url_fetcher)
|
2012-07-29 00:11:28 +04:00
|
|
|
|
else:
|
2016-08-26 15:34:28 +03:00
|
|
|
|
# Try to rely on given mimetype
|
2013-06-21 00:32:28 +04:00
|
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|
try:
|
2016-08-26 15:34:28 +03:00
|
|
|
|
if mime_type == 'image/png':
|
2020-06-22 17:05:14 +03:00
|
|
|
|
# Cairo already optimizes PNG images, no PIL needed
|
2016-08-26 15:34:28 +03:00
|
|
|
|
try:
|
|
|
|
|
surface = cairocffi.ImageSurface.create_from_png(
|
|
|
|
|
BytesIO(string))
|
|
|
|
|
except Exception as exception:
|
|
|
|
|
raise ImageLoadingError.from_exception(exception)
|
|
|
|
|
else:
|
|
|
|
|
image = RasterImage(surface)
|
|
|
|
|
else:
|
|
|
|
|
image = None
|
|
|
|
|
except ImageLoadingError:
|
|
|
|
|
image = None
|
|
|
|
|
|
|
|
|
|
# Relying on mimetype didn't work, give the image to GDK-Pixbuf
|
|
|
|
|
if not image:
|
|
|
|
|
if pixbuf is None:
|
|
|
|
|
raise ImageLoadingError(
|
2016-08-26 16:09:26 +03:00
|
|
|
|
'Could not load GDK-Pixbuf. PNG and SVG are '
|
|
|
|
|
'the only image formats available.')
|
2016-08-26 15:34:28 +03:00
|
|
|
|
try:
|
2017-06-07 12:37:53 +03:00
|
|
|
|
image = SVGImage(string, url, url_fetcher)
|
2017-10-24 11:52:33 +03:00
|
|
|
|
except BaseException:
|
2020-06-22 17:05:14 +03:00
|
|
|
|
if optimize_images:
|
|
|
|
|
try:
|
|
|
|
|
image = Image.open(BytesIO(string))
|
|
|
|
|
output = BytesIO()
|
|
|
|
|
image.save(
|
|
|
|
|
output, format=image.format, optimize=True)
|
|
|
|
|
except BaseException:
|
|
|
|
|
# Optimization did not work, keep the original
|
|
|
|
|
pass
|
|
|
|
|
else:
|
|
|
|
|
string = output.getvalue()
|
2016-11-21 11:29:55 +03:00
|
|
|
|
try:
|
|
|
|
|
surface, format_name = (
|
|
|
|
|
pixbuf.decode_to_image_surface(string))
|
|
|
|
|
except pixbuf.ImageLoadingError as exception:
|
|
|
|
|
raise ImageLoadingError(str(exception))
|
2018-03-12 21:02:07 +03:00
|
|
|
|
if format_name == 'jpeg':
|
2016-11-21 11:29:55 +03:00
|
|
|
|
surface.set_mime_data('image/jpeg', string)
|
|
|
|
|
image = RasterImage(surface)
|
2013-06-21 00:32:28 +04:00
|
|
|
|
except (URLFetchingError, ImageLoadingError) as exc:
|
2017-07-25 14:59:56 +03:00
|
|
|
|
LOGGER.error('Failed to load image at "%s" (%s)', url, exc)
|
2012-09-26 18:59:40 +04:00
|
|
|
|
image = None
|
2013-06-21 00:32:28 +04:00
|
|
|
|
cache[url] = image
|
2012-09-26 18:59:40 +04:00
|
|
|
|
return image
|
2013-04-04 21:48:23 +04:00
|
|
|
|
|
|
|
|
|
|
2013-04-08 19:28:46 +04:00
|
|
|
|
def process_color_stops(gradient_line_size, positions):
|
2013-04-04 21:48:23 +04:00
|
|
|
|
"""
|
|
|
|
|
Gradient line size: distance between the starting point and ending point.
|
2013-04-08 19:28:46 +04:00
|
|
|
|
Positions: list of None, or Dimension in px or %.
|
|
|
|
|
0 is the starting point, 1 the ending point.
|
2013-04-04 21:48:23 +04:00
|
|
|
|
|
|
|
|
|
http://dev.w3.org/csswg/css-images-3/#color-stop-syntax
|
|
|
|
|
|
|
|
|
|
Return processed color stops, as a list of floats in px.
|
|
|
|
|
|
|
|
|
|
"""
|
2019-06-02 19:06:25 +03:00
|
|
|
|
positions = [
|
|
|
|
|
percentage(position, gradient_line_size) for position in positions]
|
2013-04-04 21:48:23 +04:00
|
|
|
|
# First and last default to 100%
|
|
|
|
|
if positions[0] is None:
|
|
|
|
|
positions[0] = 0
|
|
|
|
|
if positions[-1] is None:
|
|
|
|
|
positions[-1] = gradient_line_size
|
|
|
|
|
|
|
|
|
|
# Make sure positions are increasing.
|
|
|
|
|
previous_pos = positions[0]
|
|
|
|
|
for i, position in enumerate(positions):
|
|
|
|
|
if position is not None:
|
|
|
|
|
if position < previous_pos:
|
|
|
|
|
positions[i] = previous_pos
|
|
|
|
|
else:
|
|
|
|
|
previous_pos = position
|
|
|
|
|
|
|
|
|
|
# Assign missing values
|
|
|
|
|
previous_i = -1
|
|
|
|
|
for i, position in enumerate(positions):
|
|
|
|
|
if position is not None:
|
|
|
|
|
base = positions[previous_i]
|
|
|
|
|
increment = (position - base) / (i - previous_i)
|
2018-01-14 03:48:17 +03:00
|
|
|
|
for j in range(previous_i + 1, i):
|
2013-04-04 21:48:23 +04:00
|
|
|
|
positions[j] = base + j * increment
|
|
|
|
|
previous_i = i
|
2013-04-12 17:29:21 +04:00
|
|
|
|
return positions
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
def normalize_stop_postions(positions):
|
|
|
|
|
"""Normalize to [0..1]."""
|
|
|
|
|
first = positions[0]
|
|
|
|
|
last = positions[-1]
|
2013-04-08 19:28:46 +04:00
|
|
|
|
total_length = last - first
|
2013-04-17 18:57:17 +04:00
|
|
|
|
if total_length != 0:
|
|
|
|
|
positions = [(pos - first) / total_length for pos in positions]
|
|
|
|
|
else:
|
|
|
|
|
positions = [0 for _ in positions]
|
|
|
|
|
return first, last, positions
|
2013-04-04 21:48:23 +04:00
|
|
|
|
|
|
|
|
|
|
2013-04-08 19:28:46 +04:00
|
|
|
|
def gradient_average_color(colors, positions):
|
|
|
|
|
"""
|
|
|
|
|
http://dev.w3.org/csswg/css-images-3/#find-the-average-color-of-a-gradient
|
|
|
|
|
"""
|
|
|
|
|
nb_stops = len(positions)
|
2013-04-12 17:29:21 +04:00
|
|
|
|
assert nb_stops > 1
|
2013-04-08 19:28:46 +04:00
|
|
|
|
assert nb_stops == len(colors)
|
|
|
|
|
total_length = positions[-1] - positions[0]
|
|
|
|
|
if total_length == 0:
|
2013-04-17 15:10:36 +04:00
|
|
|
|
positions = list(range(nb_stops))
|
2013-04-08 19:28:46 +04:00
|
|
|
|
total_length = nb_stops - 1
|
|
|
|
|
premul_r = [r * a for r, g, b, a in colors]
|
|
|
|
|
premul_g = [g * a for r, g, b, a in colors]
|
|
|
|
|
premul_b = [b * a for r, g, b, a in colors]
|
|
|
|
|
alpha = [a for r, g, b, a in colors]
|
|
|
|
|
result_r = result_g = result_b = result_a = 0
|
|
|
|
|
total_weight = 2 * total_length
|
|
|
|
|
for i, position in enumerate(positions[1:], 1):
|
|
|
|
|
weight = (position - positions[i - 1]) / total_weight
|
|
|
|
|
for j in (i - 1, i):
|
|
|
|
|
result_r += premul_r[j] * weight
|
|
|
|
|
result_g += premul_g[j] * weight
|
|
|
|
|
result_b += premul_b[j] * weight
|
|
|
|
|
result_a += alpha[j] * weight
|
|
|
|
|
# Un-premultiply:
|
|
|
|
|
return (result_r / result_a, result_g / result_a,
|
2013-04-17 18:57:17 +04:00
|
|
|
|
result_b / result_a, result_a) if result_a != 0 else (0, 0, 0, 0)
|
2013-04-08 19:28:46 +04:00
|
|
|
|
|
|
|
|
|
|
|
|
|
|
PATTERN_TYPES = dict(
|
|
|
|
|
linear=cairocffi.LinearGradient,
|
2013-04-11 12:39:23 +04:00
|
|
|
|
radial=cairocffi.RadialGradient,
|
2013-04-08 19:28:46 +04:00
|
|
|
|
solid=cairocffi.SolidPattern)
|
|
|
|
|
|
|
|
|
|
|
2020-01-02 14:06:58 +03:00
|
|
|
|
class Gradient:
|
2013-04-11 12:39:23 +04:00
|
|
|
|
def __init__(self, color_stops, repeating):
|
2013-04-12 17:29:21 +04:00
|
|
|
|
assert color_stops
|
2013-04-11 12:39:23 +04:00
|
|
|
|
#: List of (r, g, b, a), list of Dimension
|
2013-04-11 18:06:28 +04:00
|
|
|
|
self.colors = [color for color, position in color_stops]
|
|
|
|
|
self.stop_positions = [position for color, position in color_stops]
|
2013-04-11 12:39:23 +04:00
|
|
|
|
#: bool
|
|
|
|
|
self.repeating = repeating
|
|
|
|
|
|
2016-02-26 15:58:47 +03:00
|
|
|
|
def get_intrinsic_size(self, _image_resolution, _font_size):
|
|
|
|
|
# Gradients are not affected by image resolution, parent or font size.
|
2013-07-26 19:26:30 +04:00
|
|
|
|
return None, None
|
|
|
|
|
|
|
|
|
|
intrinsic_ratio = None
|
|
|
|
|
|
2013-04-08 19:28:46 +04:00
|
|
|
|
def draw(self, context, concrete_width, concrete_height, _image_rendering):
|
|
|
|
|
scale_y, type_, init, stop_positions, stop_colors = self.layout(
|
2013-04-11 12:39:23 +04:00
|
|
|
|
concrete_width, concrete_height, context.user_to_device_distance)
|
2013-04-08 19:28:46 +04:00
|
|
|
|
context.scale(1, scale_y)
|
|
|
|
|
pattern = PATTERN_TYPES[type_](*init)
|
|
|
|
|
for position, color in zip(stop_positions, stop_colors):
|
|
|
|
|
pattern.add_color_stop_rgba(position, *color)
|
|
|
|
|
pattern.set_extend(cairocffi.EXTEND_REPEAT if self.repeating
|
|
|
|
|
else cairocffi.EXTEND_PAD)
|
|
|
|
|
context.set_source(pattern)
|
|
|
|
|
context.paint()
|
|
|
|
|
|
2013-04-11 18:06:28 +04:00
|
|
|
|
def layout(self, width, height, user_to_device_distance):
|
2013-04-08 19:28:46 +04:00
|
|
|
|
"""width, height: Gradient box. Top-left is at coordinates (0, 0).
|
2013-04-11 18:06:28 +04:00
|
|
|
|
user_to_device_distance: a (dx, dy) -> (ddx, ddy) function
|
2013-04-08 19:28:46 +04:00
|
|
|
|
|
|
|
|
|
Returns (scale_y, type_, init, positions, colors).
|
|
|
|
|
scale_y: float, used for ellipses radial gradients. 1 otherwise.
|
|
|
|
|
positions: list of floats in [0..1].
|
|
|
|
|
0 at the starting point, 1 at the ending point.
|
|
|
|
|
colors: list of (r, g, b, a)
|
|
|
|
|
type_ is either:
|
|
|
|
|
'solid': init is (r, g, b, a). positions and colors are empty.
|
|
|
|
|
'linear': init is (x0, y0, x1, y1)
|
2013-04-11 12:39:23 +04:00
|
|
|
|
coordinates of the starting and ending points.
|
|
|
|
|
'radial': init is (cx0, cy0, radius0, cx1, cy1, radius1)
|
|
|
|
|
coordinates of the starting end ending circles
|
2013-04-08 19:28:46 +04:00
|
|
|
|
|
|
|
|
|
"""
|
|
|
|
|
raise NotImplementedError
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
class LinearGradient(Gradient):
|
2013-04-04 21:48:23 +04:00
|
|
|
|
def __init__(self, color_stops, direction, repeating):
|
2013-04-11 18:06:28 +04:00
|
|
|
|
Gradient.__init__(self, color_stops, repeating)
|
2013-04-11 12:39:23 +04:00
|
|
|
|
#: ('corner', keyword) or ('angle', radians)
|
2013-04-04 21:48:23 +04:00
|
|
|
|
self.direction_type, self.direction = direction
|
|
|
|
|
|
2013-04-11 12:39:23 +04:00
|
|
|
|
def layout(self, width, height, user_to_device_distance):
|
2013-04-12 17:29:21 +04:00
|
|
|
|
if len(self.colors) == 1:
|
|
|
|
|
return 1, 'solid', self.colors[0], [], []
|
2013-04-11 12:39:23 +04:00
|
|
|
|
# (dx, dy) is the unit vector giving the direction of the gradient.
|
|
|
|
|
# Positive dx: right, positive dy: down.
|
2013-04-04 21:48:23 +04:00
|
|
|
|
if self.direction_type == 'corner':
|
|
|
|
|
factor_x, factor_y = {
|
|
|
|
|
'top_left': (-1, -1), 'top_right': (1, -1),
|
|
|
|
|
'bottom_left': (-1, 1), 'bottom_right': (1, 1)}[self.direction]
|
2013-04-08 19:28:46 +04:00
|
|
|
|
diagonal = math.hypot(width, height)
|
2013-04-12 17:29:21 +04:00
|
|
|
|
# Note the direction swap: dx based on height, dy based on width
|
|
|
|
|
# The gradient line is perpendicular to a diagonal.
|
2013-04-11 12:39:23 +04:00
|
|
|
|
dx = factor_x * height / diagonal
|
|
|
|
|
dy = factor_y * width / diagonal
|
2013-04-04 21:48:23 +04:00
|
|
|
|
else:
|
2013-04-08 19:28:46 +04:00
|
|
|
|
angle = self.direction # 0 upwards, then clockwise
|
2013-04-11 12:39:23 +04:00
|
|
|
|
dx = math.sin(angle)
|
|
|
|
|
dy = -math.cos(angle)
|
2013-04-12 17:29:21 +04:00
|
|
|
|
# Distance between center and ending point,
|
|
|
|
|
# ie. half of between the starting point and ending point:
|
|
|
|
|
distance = abs(width * dx) + abs(height * dy)
|
2013-04-17 18:57:17 +04:00
|
|
|
|
positions = process_color_stops(distance, self.stop_positions)
|
|
|
|
|
first, last, positions = normalize_stop_postions(positions)
|
|
|
|
|
device_per_user_units = math.hypot(*user_to_device_distance(dx, dy))
|
|
|
|
|
if (last - first) * device_per_user_units < len(positions):
|
|
|
|
|
if self.repeating:
|
|
|
|
|
color = gradient_average_color(self.colors, positions)
|
|
|
|
|
return 1, 'solid', color, [], []
|
|
|
|
|
else:
|
|
|
|
|
# 100 is an Arbitrary non-zero number of device units.
|
|
|
|
|
offset = 100 / device_per_user_units
|
|
|
|
|
if first != last:
|
|
|
|
|
factor = (offset + last - first) / (last - first)
|
|
|
|
|
positions = [pos / factor for pos in positions]
|
|
|
|
|
last += offset
|
2013-04-12 17:29:21 +04:00
|
|
|
|
start_x = (width - dx * distance) / 2
|
|
|
|
|
start_y = (height - dy * distance) / 2
|
|
|
|
|
points = (start_x + dx * first, start_y + dy * first,
|
|
|
|
|
start_x + dx * last, start_y + dy * last)
|
2013-04-11 12:39:23 +04:00
|
|
|
|
return 1, 'linear', points, positions, self.colors
|
2013-04-08 19:28:46 +04:00
|
|
|
|
|
|
|
|
|
|
|
|
|
|
class RadialGradient(Gradient):
|
2013-04-11 18:06:28 +04:00
|
|
|
|
def __init__(self, color_stops, shape, size, center, repeating):
|
|
|
|
|
Gradient.__init__(self, color_stops, repeating)
|
2013-04-11 12:39:23 +04:00
|
|
|
|
# Center of the ending shape. (origin_x, pos_x, origin_y, pos_y)
|
2013-04-11 18:06:28 +04:00
|
|
|
|
self.center = center
|
2013-04-11 12:39:23 +04:00
|
|
|
|
#: Type of ending shape: 'circle' or 'ellipse'
|
|
|
|
|
self.shape = shape
|
|
|
|
|
# size_type: 'keyword'
|
|
|
|
|
# size: 'closest-corner', 'farthest-corner',
|
|
|
|
|
# 'closest-side', or 'farthest-side'
|
|
|
|
|
# size_type: 'explicit'
|
|
|
|
|
# size: (radius_x, radius_y)
|
|
|
|
|
self.size_type, self.size = size
|
|
|
|
|
|
2013-04-16 18:18:47 +04:00
|
|
|
|
def layout(self, width, height, user_to_device_distance):
|
2013-04-12 17:29:21 +04:00
|
|
|
|
if len(self.colors) == 1:
|
|
|
|
|
return 1, 'solid', self.colors[0], [], []
|
2013-04-11 18:06:28 +04:00
|
|
|
|
origin_x, center_x, origin_y, center_y = self.center
|
2019-06-02 19:06:25 +03:00
|
|
|
|
center_x = percentage(center_x, width)
|
|
|
|
|
center_y = percentage(center_y, height)
|
2013-04-11 12:39:23 +04:00
|
|
|
|
if origin_x == 'right':
|
2013-04-11 18:06:28 +04:00
|
|
|
|
center_x = width - center_x
|
2013-04-11 12:39:23 +04:00
|
|
|
|
if origin_y == 'bottom':
|
2013-04-11 18:06:28 +04:00
|
|
|
|
center_y = height - center_y
|
2013-04-11 12:39:23 +04:00
|
|
|
|
|
2013-04-16 18:18:47 +04:00
|
|
|
|
size_x, size_y = self._resolve_size(width, height, center_x, center_y)
|
2013-04-11 12:39:23 +04:00
|
|
|
|
# http://dev.w3.org/csswg/css-images-3/#degenerate-radials
|
|
|
|
|
if size_x == size_y == 0:
|
2013-04-16 18:18:47 +04:00
|
|
|
|
size_x = size_y = 1e-7
|
2013-04-11 12:39:23 +04:00
|
|
|
|
elif size_x == 0:
|
2013-04-16 18:18:47 +04:00
|
|
|
|
size_x = 1e-7
|
|
|
|
|
size_y = 1e7
|
2013-04-11 12:39:23 +04:00
|
|
|
|
elif size_y == 0:
|
2013-04-16 18:18:47 +04:00
|
|
|
|
size_x = 1e7
|
|
|
|
|
size_y = 1e-7
|
2013-04-11 12:39:23 +04:00
|
|
|
|
scale_y = size_y / size_x
|
|
|
|
|
|
|
|
|
|
colors = self.colors
|
2013-04-12 17:29:21 +04:00
|
|
|
|
positions = process_color_stops(size_x, self.stop_positions)
|
|
|
|
|
gradient_line_size = positions[-1] - positions[0]
|
2013-04-11 12:39:23 +04:00
|
|
|
|
if self.repeating and any(
|
2013-04-17 18:57:17 +04:00
|
|
|
|
gradient_line_size * unit < len(positions)
|
|
|
|
|
for unit in (math.hypot(*user_to_device_distance(1, 0)),
|
|
|
|
|
math.hypot(*user_to_device_distance(0, scale_y)))):
|
2013-04-11 12:39:23 +04:00
|
|
|
|
color = gradient_average_color(colors, positions)
|
|
|
|
|
return 1, 'solid', color, [], []
|
|
|
|
|
|
2013-04-12 17:29:21 +04:00
|
|
|
|
if positions[0] < 0:
|
2013-04-11 12:39:23 +04:00
|
|
|
|
# Cairo does not like negative radiuses,
|
|
|
|
|
# shift into the positive realm.
|
|
|
|
|
if self.repeating:
|
|
|
|
|
offset = gradient_line_size * math.ceil(
|
2013-04-12 17:29:21 +04:00
|
|
|
|
-positions[0] / gradient_line_size)
|
2013-04-11 12:39:23 +04:00
|
|
|
|
positions = [p + offset for p in positions]
|
|
|
|
|
else:
|
|
|
|
|
for i, position in enumerate(positions):
|
2013-04-16 18:18:47 +04:00
|
|
|
|
if position > 0:
|
2013-04-12 17:29:21 +04:00
|
|
|
|
# `i` is the first positive stop.
|
|
|
|
|
# Interpolate with the previous to get the color at 0.
|
|
|
|
|
assert i > 0
|
2013-04-11 12:39:23 +04:00
|
|
|
|
color = colors[i]
|
|
|
|
|
neg_color = colors[i - 1]
|
|
|
|
|
neg_position = positions[i - 1]
|
|
|
|
|
assert neg_position < 0
|
|
|
|
|
intermediate_color = gradient_average_color(
|
2013-04-16 18:18:47 +04:00
|
|
|
|
[neg_color, neg_color, color, color],
|
2013-04-11 12:39:23 +04:00
|
|
|
|
[neg_position, 0, 0, position])
|
|
|
|
|
colors = [intermediate_color] + colors[i:]
|
|
|
|
|
positions = [0] + positions[i:]
|
|
|
|
|
break
|
|
|
|
|
else:
|
2013-04-12 17:29:21 +04:00
|
|
|
|
# All stops are negatives,
|
|
|
|
|
# everything is "padded" with the last color.
|
2013-04-11 12:39:23 +04:00
|
|
|
|
return 1, 'solid', self.colors[-1], [], []
|
|
|
|
|
|
2013-04-12 17:29:21 +04:00
|
|
|
|
first, last, positions = normalize_stop_postions(positions)
|
2013-04-17 18:57:17 +04:00
|
|
|
|
if last == first:
|
|
|
|
|
last += 100 # Arbitrary non-zero
|
|
|
|
|
|
2013-04-16 18:18:47 +04:00
|
|
|
|
circles = (center_x, center_y / scale_y, first,
|
|
|
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center_x, center_y / scale_y, last)
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2013-04-11 12:39:23 +04:00
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return scale_y, 'radial', circles, positions, colors
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2013-04-11 18:06:28 +04:00
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def _resolve_size(self, width, height, center_x, center_y):
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2013-04-11 12:39:23 +04:00
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if self.size_type == 'explicit':
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2013-04-16 18:18:47 +04:00
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|
size_x, size_y = self.size
|
2019-06-02 19:06:25 +03:00
|
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|
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size_x = percentage(size_x, width)
|
|
|
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size_y = percentage(size_y, height)
|
2019-06-01 02:32:13 +03:00
|
|
|
|
return size_x, size_y
|
2013-04-11 18:06:28 +04:00
|
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|
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left = abs(center_x)
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|
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right = abs(width - center_x)
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top = abs(center_y)
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bottom = abs(height - center_y)
|
2013-04-16 18:18:47 +04:00
|
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|
pick = min if self.size.startswith('closest') else max
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|
|
|
if self.size.endswith('side'):
|
2013-04-11 12:39:23 +04:00
|
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|
|
if self.shape == 'circle':
|
2013-04-16 18:18:47 +04:00
|
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|
|
size_xy = pick(left, right, top, bottom)
|
2013-04-11 12:39:23 +04:00
|
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|
|
return size_xy, size_xy
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|
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|
# else: ellipse
|
2013-04-16 18:18:47 +04:00
|
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|
|
return pick(left, right), pick(top, bottom)
|
|
|
|
|
# else: corner
|
|
|
|
|
if self.shape == 'circle':
|
|
|
|
|
size_xy = pick(math.hypot(left, top), math.hypot(left, bottom),
|
|
|
|
|
math.hypot(right, top), math.hypot(right, bottom))
|
|
|
|
|
return size_xy, size_xy
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|
|
|
|
# else: ellipse
|
|
|
|
|
corner_x, corner_y = pick(
|
|
|
|
|
(left, top), (left, bottom), (right, top), (right, bottom),
|
|
|
|
|
key=lambda a: math.hypot(*a))
|
|
|
|
|
return corner_x * math.sqrt(2), corner_y * math.sqrt(2)
|