def getter(self):
lines = getter_getter(self)()
length = lines.GetNumberOfCells()
if length:
arr = vtk_to_numpy(lines.GetData())
return unpack_lengths(arr)
else:
return []
def points(self):
points = self.vtk_polydata.GetPoints()
if points is None:
return None
else:
data = points.GetData()
self._temp.append(data)
return vtk_to_numpy(data)
def write(arr, path, format=None, quality=95):
"""Write an image from a file using one of VTK's ``vtkFormatWriter`` classes
where ``Format`` is replaced by JPEG or PNG.
:param arr: **arr** can be a `vtkImageData`_ or a numpy array.
:type arr: np.ndarray
:param path: File path to write to.
:type path: str, os.Pathlike, io.BytesIO,
:param format: Image format extension (e.g. jpg), not needed if format can be determined from **path**, defaults to ``None``.
:type format: str, optional
:param quality: Lossy compression quality, only applicable to JPEGs, defaults to 95.
:type quality: int from 0 to 100, optional
:return: The raw image binary if ``path is None``, ``NotImplemented`` if the filetype is unknown. Otherwise no return value.
:rtype: bytes
See :meth:`read` for more information.
.. note::
BytesIO and raw bytes functionality is new in vtkplotlib >= 1.3.0.
Older versions are hardcoded to write to disk and therefore **path**
must be a filename and not a BytesIO or similar pseudo file object.
"""
format = _normalise_format(path, format)
try:
Writer = getattr(vtk, "vtk{}Writer".format(format))
except AttributeError:
return NotImplemented
im_data = as_vtkimagedata(arr)
im_data.Modified()
writer = Writer()
writer.SetInputDataObject(im_data)
if Writer is vtk.vtkJPEGWriter:
writer.SetQuality(quality)
if nuts_and_bolts.isinstance_PathLike(path):
with PathHandler(path, "w") as path_handler:
writer.SetFileName(path_handler.access_path)
writer.Update()
writer.Write()
return
writer.WriteToMemoryOn()
writer.Update()
writer.Write()
binary = vtk_to_numpy(writer.GetResult()).tobytes()
if path is None:
return binary
path.write(binary)
def vtkimagedata_to_array(image_data):
"""Convert a vtkImageData to numpy array.
.. seealso:: :meth:`vtkimagedata_from_array` for the reverse.
"""
points = vtk_to_numpy(image_data.GetPointData().GetScalars())
shape = image_data.GetDimensions()
# Be careful here. shape[2] isn't the number of values per pixel as you'd
# expect. Rather it is a 3rd dimension as vtkImageData is
# supposed to hold volumes. `image_data.GetNumberOfScalarComponents()` gets
# the right value (usually 3 for RGB).
# Additionally vtk uses cartesian coordinates in images which isn't the
# norm - hence the axes swapping and mirroring.
shape = (shape[1], shape[0], image_data.GetNumberOfScalarComponents())
return points.reshape(shape)[::-1]
def getter(self):
colors = getter_getter(self)().GetScalars()
if colors is None:
return
return vtk_to_numpy(colors)
