volume¶
Submodule extending the vtkVolume
object functionality.
Volume¶

class
vtkplotter.volume.
Volume
(inputobj, c=('b', 'lb', 'lg', 'y', 'r'), alpha=(0.0, 0.0, 0.2, 0.4, 0.8, 1), alphaGradient=None, mode=0, origin=None, spacing=None, shape=None, mapperType='gpu')[source]¶ Bases:
vtkRenderingCorePython.vtkVolume
,vtkplotter.base.ActorBase
Derived class of
vtkVolume
. Can be initialized with a numpy object, see e.g.: numpy2volume.py Parameters
c (float, list) – sets colors along the scalar range, or a matplotlib color map name
alphas – sets transparencies along the scalar range
origin (list) – set volume origin coordinates
spacing (list) – voxel dimensions in x, y and z.
shape (list) – specify the shape.
mapperType (str) – either ‘gpu’, ‘opengl_gpu’, ‘fixed’ or ‘smart’
mode (int) –
define the volumetric rendering style:
0, Composite rendering
1, maximum projection rendering
2, minimum projection
3, average projection
4, additive mode
Hint
if a list of values is used for alphas this is interpreted as a transfer function along the range of the scalar.

alpha
(alpha)[source]¶ Assign a set of tranparencies to a volume along the range of the scalar value. A single constant value can also be assigned.
E.g.: say alpha=(0.0, 0.3, 0.9, 1) and the scalar range goes from 10 to 150. Then all voxels with a value close to 10 will be completely transparent, voxels at 1/4 of the range will get an alpha equal to 0.3 and voxels with value close to 150 will be completely opaque.

alphaGradient
(alphaGrad)[source]¶ Assign a set of tranparencies to a volume’s gradient along the range of the scalar value. A single constant value can also be assigned. The gradient function is used to decrease the opacity in the “flat” regions of the volume while maintaining the opacity at the boundaries between material types. The gradient is measured as the amount by which the intensity changes over unit distance.

append
(volumes, axis='z', preserveExtents=False)[source]¶ Take the components from multiple inputs and merges them into one output. Except for the append axis, all inputs must have the same extent. All inputs must have the same number of scalar components. The output has the same origin and spacing as the first input. The origin and spacing of all other inputs are ignored. All inputs must have the same scalar type.
 Parameters
preserveExtents (bool) – if True, the extent of the inputs is used to place the image in the output. The whole extent of the output is the union of the input whole extents. Any portion of the output not covered by the inputs is set to zero. The origin and spacing is taken from the first input.
from vtkplotter import load, datadir vol = load(datadir+'embryo.tif') vol.append(vol, axis='x').show()

center
(center=None)[source]¶ Set/get the volume coordinates of its center. Position is reset to (0,0,0).

color
(col)[source]¶ Assign a color or a set of colors to a volume along the range of the scalar value. A single constant color can also be assigned. Any matplotlib color map name is also accepted, e.g.
volume.color('jet')
.E.g.: say that your voxel scalar runs from 3 to 6, and you want 3 to show red and 1.5 violet and 6 green, then just set:
volume.color(['red', 'violet', 'green'])

crop
(top=None, bottom=None, right=None, left=None, front=None, back=None, VOI=())[source]¶ Crop a
Volume
object. Parameters
top (float) – fraction to crop from the top plane (positive z)
bottom (float) – fraction to crop from the bottom plane (negative z)
front (float) – fraction to crop from the front plane (positive y)
back (float) – fraction to crop from the back plane (negative y)
right (float) – fraction to crop from the right plane (positive x)
left (float) – fraction to crop from the left plane (negative x)
VOI (list) –
extract Volume Of Interest expressed in voxel numbers
Eg.: vol.crop(VOI=(xmin, xmax, ymin, ymax, zmin, zmax)) # all integers nrs

cutWithPlane
(origin=(0, 0, 0), normal=(1, 0, 0))[source]¶ Cuts
Volume
with the plane defined by a point and a normal creating a tetrahedral mesh object. Makes sense only if the plane is not along any of the cartesian planes, otherwise usecrop()
which is way faster. Parameters
origin – the cutting plane goes through this point
normal – normal of the cutting plane

isosurface
(threshold=True, connectivity=False)[source]¶ Return an
Mesh
isosurface extracted from theVolume
object. Parameters

jittering
(status=None)[source]¶ If jittering is True, each ray traversal direction will be perturbed slightly using a noisetexture to get rid of woodgrain effects.

legosurface
(vmin=None, vmax=None, cmap='afmhot_r')[source]¶ Represent a
Volume
as lego blocks (voxels). By default colors correspond to the volume’s scalar. Returns anMesh
. Parameters

mirror
(axis='x')[source]¶ Mirror flip along one of the cartesian axes.
Note
axis='n'
, will flip only mesh normals.

mode
(mode=None)[source]¶ Define the volumetric rendering style.
0, Composite rendering
1, maximum projection rendering
2, minimum projection
3, average projection
4, additive mode

permuteAxes
(x, y, z)[source]¶ Reorder the axes of the Volume by specifying the input axes which are supposed to become the new X, Y, and Z.

resample
(newSpacing, interpolation=1)[source]¶ Resamples a
Volume
to be larger or smaller.This method modifies the spacing of the input. Linear interpolation is used to resample the data.