def lines_to_vtk_polydata(lines, colors=None):
"""Create a vtkPolyData with lines and colors.
Parameters
----------
lines : list
list of N curves represented as 2D ndarrays
colors : array (N, 3), list of arrays, tuple (3,), array (K,)
If None or False, a standard orientation colormap is used for every
line.
If one tuple of color is used. Then all streamlines will have the same
colour.
If an array (N, 3) is given, where N is equal to the number of lines.
Then every line is coloured with a different RGB color.
If a list of RGB arrays is given then every point of every line takes
a different color.
If an array (K, 3) is given, where K is the number of points of all
lines then every point is colored with a different RGB color.
If an array (K,) is given, where K is the number of points of all
lines then these are considered as the values to be used by the
colormap.
If an array (L,) is given, where L is the number of streamlines then
these are considered as the values to be used by the colormap per
streamline.
If an array (X, Y, Z) or (X, Y, Z, 3) is given then the values for the
colormap are interpolated automatically using trilinear interpolation.
Returns
-------
poly_data : vtkPolyData
color_is_scalar : bool, true if the color array is a single scalar
Scalar array could be used with a colormap lut
None if no color was used
"""
# Get the 3d points_array
points_array = np.vstack(lines)
# Set Points to vtk array format
vtk_points = numpy_to_vtk_points(points_array)
# Set Lines to vtk array format
vtk_cell_array = numpy_to_vtk_cells(lines)
# Create the poly_data
poly_data = PolyData()
poly_data.SetPoints(vtk_points)
poly_data.SetLines(vtk_cell_array)
# Get colors_array (reformat to have colors for each points)
# - if/else tested and work in normal simple case
nb_points = len(points_array)
nb_lines = len(lines)
lines_range = range(nb_lines)
points_per_line = [len(lines[i]) for i in lines_range]
points_per_line = np.array(points_per_line, np.intp)
color_is_scalar = False
if colors is None or colors is False:
# set automatic rgb colors
cols_arr = line_colors(lines)
colors_mapper = np.repeat(lines_range, points_per_line, axis=0)
vtk_colors = numpy_to_vtk_colors(255 * cols_arr[colors_mapper])
else:
cols_arr = np.asarray(colors)
if cols_arr.dtype == object: # colors is a list of colors
vtk_colors = numpy_to_vtk_colors(255 * np.vstack(colors))
else:
if len(cols_arr) == nb_points:
if cols_arr.ndim == 1: # values for every point
vtk_colors = numpy_support.numpy_to_vtk(cols_arr,
deep=True)
color_is_scalar = True
elif cols_arr.ndim == 2: # map color to each point
vtk_colors = numpy_to_vtk_colors(255 * cols_arr)
elif cols_arr.ndim == 1:
if len(cols_arr) == nb_lines: # values for every streamline
cols_arrx = []
for (i, value) in enumerate(colors):
cols_arrx += lines[i].shape[0] * [value]
cols_arrx = np.array(cols_arrx)
vtk_colors = numpy_support.numpy_to_vtk(cols_arrx,
deep=True)
color_is_scalar = True
else: # the same colors for all points
vtk_colors = numpy_to_vtk_colors(
np.tile(255 * cols_arr, (nb_points, 1)))
elif cols_arr.ndim == 2: # map color to each line
colors_mapper = np.repeat(lines_range, points_per_line, axis=0)
vtk_colors = numpy_to_vtk_colors(255 * cols_arr[colors_mapper])
else: # colormap
# get colors for each vertex
cols_arr = map_coordinates_3d_4d(cols_arr, points_array)
vtk_colors = numpy_support.numpy_to_vtk(cols_arr, deep=True)
color_is_scalar = True
vtk_colors.SetName("colors")
poly_data.GetPointData().SetScalars(vtk_colors)
return poly_data, color_is_scalar
def __init__(self,
directions,
indices,
values=None,
affine=None,
colors=None,
lookup_colormap=None,
linewidth=1,
symmetric=True):
if affine is not None:
w_pos = apply_affine(affine, np.asarray(indices).T)
valid_dirs = directions[indices]
num_dirs = len(np.nonzero(np.abs(valid_dirs).max(axis=-1) > 0)[0])
pnts_per_line = 2
points_array = np.empty((num_dirs * pnts_per_line, 3))
centers_array = np.empty_like(points_array, dtype=int)
diffs_array = np.empty_like(points_array)
line_count = 0
for idx, center in enumerate(zip(indices[0], indices[1], indices[2])):
if affine is None:
xyz = np.asarray(center)
else:
xyz = w_pos[idx, :]
valid_peaks = np.nonzero(
np.abs(valid_dirs[idx, :, :]).max(axis=-1) > 0.)[0]
for direction in valid_peaks:
if values is not None:
pv = values[center][direction]
else:
pv = 1.
if symmetric:
point_i = directions[center][direction] * pv + xyz
point_e = -directions[center][direction] * pv + xyz
else:
point_i = directions[center][direction] * pv + xyz
point_e = xyz
diff = point_e - point_i
points_array[line_count * pnts_per_line, :] = point_e
points_array[line_count * pnts_per_line + 1, :] = point_i
centers_array[line_count * pnts_per_line, :] = center
centers_array[line_count * pnts_per_line + 1, :] = center
diffs_array[line_count * pnts_per_line, :] = diff
diffs_array[line_count * pnts_per_line + 1, :] = diff
line_count += 1
vtk_points = numpy_to_vtk_points(points_array)
vtk_cells = _points_to_vtk_cells(points_array)
colors_tuple = _peaks_colors_from_points(points_array, colors=colors)
vtk_colors, colors_are_scalars, self.__global_opacity = colors_tuple
poly_data = PolyData()
poly_data.SetPoints(vtk_points)
poly_data.SetLines(vtk_cells)
poly_data.GetPointData().SetScalars(vtk_colors)
self.__mapper = PolyDataMapper()
self.__mapper.SetInputData(poly_data)
self.__mapper.ScalarVisibilityOn()
self.__mapper.SetScalarModeToUsePointFieldData()
self.__mapper.SelectColorArray('colors')
self.__mapper.Update()
self.SetMapper(self.__mapper)
attribute_to_actor(self, centers_array, 'center')
attribute_to_actor(self, diffs_array, 'diff')
vs_dec_code = import_fury_shader('peak_dec.vert')
vs_impl_code = import_fury_shader('peak_impl.vert')
fs_dec_code = import_fury_shader('peak_dec.frag')
fs_impl_code = import_fury_shader('peak_impl.frag')
shader_to_actor(self,
'vertex',
decl_code=vs_dec_code,
impl_code=vs_impl_code)
shader_to_actor(self, 'fragment', decl_code=fs_dec_code)
shader_to_actor(self,
'fragment',
impl_code=fs_impl_code,
block='light')
# Color scale with a lookup table
if colors_are_scalars:
if lookup_colormap is None:
lookup_colormap = colormap_lookup_table()
self.__mapper.SetLookupTable(lookup_colormap)
self.__mapper.UseLookupTableScalarRangeOn()
self.__mapper.Update()
self.__lw = linewidth
self.GetProperty().SetLineWidth(self.__lw)
if self.__global_opacity >= 0:
self.GetProperty().SetOpacity(self.__global_opacity)
self.__min_centers = np.min(indices, axis=1)
self.__max_centers = np.max(indices, axis=1)
self.__is_range = True
self.__low_ranges = self.__min_centers
self.__high_ranges = self.__max_centers
self.__cross_section = self.__high_ranges // 2
self.__mapper.AddObserver(Command.UpdateShaderEvent,
self.__display_peaks_vtk_callback)
