B-Spline Geometry

BSpline module provides data storage and evaluation functions for non-rational spline geometries.

Inheritance Diagram

digraph inheritance2712a16c2b { bgcolor=transparent; rankdir=LR; ratio=compress; size="8.0, 12.0"; "geomdl.BSpline.Curve" [URL="#geomdl.BSpline.Curve",fillcolor=white,fontname="Vera Sans, DejaVu Sans, Liberation Sans, Arial, Helvetica, sans",fontsize=10,height=0.25,shape=box,style="setlinewidth(0.5),filled",target="_top",tooltip="Data storage and evaluation class for n-variate B-spline (non-rational) curves."]; "geomdl.abstract.Curve" -> "geomdl.BSpline.Curve" [arrowsize=0.5,style="setlinewidth(0.5)"]; "geomdl.BSpline.Surface" [URL="#geomdl.BSpline.Surface",fillcolor=white,fontname="Vera Sans, DejaVu Sans, Liberation Sans, Arial, Helvetica, sans",fontsize=10,height=0.25,shape=box,style="setlinewidth(0.5),filled",target="_top",tooltip="Data storage and evaluation class for B-spline (non-rational) surfaces."]; "geomdl.abstract.Surface" -> "geomdl.BSpline.Surface" [arrowsize=0.5,style="setlinewidth(0.5)"]; "geomdl.BSpline.Volume" [URL="#geomdl.BSpline.Volume",fillcolor=white,fontname="Vera Sans, DejaVu Sans, Liberation Sans, Arial, Helvetica, sans",fontsize=10,height=0.25,shape=box,style="setlinewidth(0.5),filled",target="_top",tooltip="Data storage and evaluation class for B-spline (non-rational) volumes."]; "geomdl.abstract.Volume" -> "geomdl.BSpline.Volume" [arrowsize=0.5,style="setlinewidth(0.5)"]; "geomdl.abstract.Curve" [URL="module_abstract.html#geomdl.abstract.Curve",fillcolor=white,fontname="Vera Sans, DejaVu Sans, Liberation Sans, Arial, Helvetica, sans",fontsize=10,height=0.25,shape=box,style="setlinewidth(0.5),filled",target="_top",tooltip="Abstract base class for defining spline curves."]; "geomdl.abstract.SplineGeometry" -> "geomdl.abstract.Curve" [arrowsize=0.5,style="setlinewidth(0.5)"]; "geomdl.abstract.SplineGeometry" [URL="module_abstract.html#geomdl.abstract.SplineGeometry",fillcolor=white,fontname="Vera Sans, DejaVu Sans, Liberation Sans, Arial, Helvetica, sans",fontsize=10,height=0.25,shape=box,style="setlinewidth(0.5),filled",target="_top",tooltip="Abstract base class for defining spline geometry objects."]; "geomdl.abstract.Surface" [URL="module_abstract.html#geomdl.abstract.Surface",fillcolor=white,fontname="Vera Sans, DejaVu Sans, Liberation Sans, Arial, Helvetica, sans",fontsize=10,height=0.25,shape=box,style="setlinewidth(0.5),filled",target="_top",tooltip="Abstract base class for defining spline surfaces."]; "geomdl.abstract.SplineGeometry" -> "geomdl.abstract.Surface" [arrowsize=0.5,style="setlinewidth(0.5)"]; "geomdl.abstract.Volume" [URL="module_abstract.html#geomdl.abstract.Volume",fillcolor=white,fontname="Vera Sans, DejaVu Sans, Liberation Sans, Arial, Helvetica, sans",fontsize=10,height=0.25,shape=box,style="setlinewidth(0.5),filled",target="_top",tooltip="Abstract base class for defining spline volumes."]; "geomdl.abstract.SplineGeometry" -> "geomdl.abstract.Volume" [arrowsize=0.5,style="setlinewidth(0.5)"]; }

B-Spline Curve

class geomdl.BSpline.Curve(**kwargs)

Bases: Curve

Data storage and evaluation class for n-variate B-spline (non-rational) curves.

This class provides the following properties:

type = spline
id
order
degree
knotvector
ctrlpts
delta
sample_size
bbox
vis
name
dimension
evaluator
rational

The following code segment illustrates the usage of Curve class:

from geomdl import BSpline

# Create a 3-dimensional B-spline Curve
curve = BSpline.Curve()

# Set degree
curve.degree = 3

# Set control points
curve.ctrlpts = [[10, 5, 10], [10, 20, -30], [40, 10, 25], [-10, 5, 0]]

# Set knot vector
curve.knotvector = [0, 0, 0, 0, 1, 1, 1, 1]

# Set evaluation delta (controls the number of curve points)
curve.delta = 0.05

# Get curve points (the curve will be automatically evaluated)
curve_points = curve.evalpts

Keyword Arguments:

precision: number of decimal places to round to. Default: 18
normalize_kv: activates knot vector normalization. Default: True
find_span_func: sets knot span search implementation. Default: helpers.find_span_linear()
insert_knot_func: sets knot insertion implementation. Default: operations.insert_knot()
remove_knot_func: sets knot removal implementation. Default: operations.remove_knot()

Please refer to the abstract.Curve() documentation for more details.

property bbox

Bounding box.

Evaluates the bounding box and returns the minimum and maximum coordinates.

Please refer to the wiki for details on using this class member.

Getter:: Gets the bounding box
Type:: tuple

binormal(parpos, **kwargs)

Evaluates the binormal vector of the curve at the given parametric position(s).

Parameters:: parpos (float, list or tuple) – parametric position(s) where the evaluation will be executed
Returns:: binormal vector as a tuple of the origin point and the vector components
Return type:: tuple

property cpsize

Number of control points in all parametric directions.

Note

This is an expert property for getting and setting control point size(s) of the geometry.

Please refer to the wiki for details on using this class member.

Getter:: Gets the number of control points
Setter:: Sets the number of control points
Type:: list

property ctrlpts

Control points.

Please refer to the wiki for details on using this class member.

Getter:: Gets the control points
Setter:: Sets the control points
Type:: list

property ctrlpts_size

Total number of control points.

Getter:: Gets the total number of control points
Type:: int

property data

Returns a dict which contains the geometry data.

Please refer to the wiki for details on using this class member.

property degree

Degree.

Please refer to the wiki for details on using this class member.

Getter:: Gets the degree
Setter:: Sets the degree
Type:: int

property delta

Evaluation delta.

Evaluation delta corresponds to the step size while evaluate function iterates on the knot vector to generate curve points. Decreasing step size results in generation of more curve points. Therefore; smaller the delta value, smoother the curve.

The following figure illustrates the working principles of the delta property:

$\left[{{u_{start}},{u_{start}} + \delta ,({u_{start}} + \delta ) + \delta , \ldots ,{u_{end}}} \right]$

Please refer to the wiki for details on using this class member.

Getter:: Gets the delta value
Setter:: Sets the delta value
Type:: float

derivatives(u, order=0, **kwargs)

Evaluates n-th order curve derivatives at the given parameter value.

The output of this method is list of n-th order derivatives. If order is 0, then it will only output the evaluated point. Similarly, if order is 2, then it will output the evaluated point, 1st derivative and the 2nd derivative. For instance;

# Assuming a curve (crv) is defined on a parametric domain [0.0, 1.0]
# Let's take the curve derivative at the parametric position u = 0.35
ders = crv.derivatives(u=0.35, order=2)
ders[0]  # evaluated point, equal to crv.evaluate_single(0.35)
ders[1]  # 1st derivative at u = 0.35
ders[2]  @ 2nd derivative at u = 0.35

Parameters:

u (float) – parameter value
order (int) – derivative order

Returns:

a list containing up to {order}-th derivative of the curve

Return type:

list

property dimension

Spatial dimension.

Spatial dimension will be automatically estimated from the first element of the control points array.

Please refer to the wiki for details on using this class member.

Getter:: Gets the spatial dimension, e.g. 2D, 3D, etc.
Type:: int

property domain

Domain.

Domain is determined using the knot vector(s).

Getter:: Gets the domain

property evalpts

Evaluated points.

Please refer to the wiki for details on using this class member.

Getter:: Gets the coordinates of the evaluated points
Type:: list

evaluate(**kwargs)

Evaluates the curve.

The evaluated points are stored in evalpts property.

Keyword arguments:

start: start parameter
stop: stop parameter

The start and stop parameters allow evaluation of a curve segment in the range [start, stop], i.e. the curve will also be evaluated at the stop parameter value.

The following examples illustrate the usage of the keyword arguments.

# Start evaluating from u=0.2 to u=1.0
curve.evaluate(start=0.2)

# Start evaluating from u=0.0 to u=0.7
curve.evaluate(stop=0.7)

# Start evaluating from u=0.1 to u=0.5
curve.evaluate(start=0.1, stop=0.5)

# Get the evaluated points
curve_points = curve.evalpts

evaluate_list(param_list)

Evaluates the curve for an input range of parameters.

Parameters:: param_list (list, tuple) – list of parameters
Returns:: evaluated surface points at the input parameters
Return type:: list

evaluate_single(param)

Evaluates the curve at the input parameter.

Parameters:: param (float) – parameter
Returns:: evaluated surface point at the given parameter
Return type:: list

property evaluator

Evaluator instance.

Evaluators allow users to use different algorithms for B-Spline and NURBS evaluations. Please see the documentation on Evaluator classes.

Please refer to the wiki for details on using this class member.

Getter:: Gets the current Evaluator instance
Setter:: Sets the Evaluator instance
Type:: evaluators.AbstractEvaluator

property id

Object ID (as an integer).

Please refer to the wiki for details on using this class member.

Getter:: Gets the object ID
Setter:: Sets the object ID
Type:: int

insert_knot(param, **kwargs)

Inserts the knot and updates the control points array and the knot vector.

Keyword Arguments:

num: Number of knot insertions. Default: 1

Parameters:: param (float) – knot to be inserted

property knotvector

Knot vector.

The knot vector will be normalized to [0, 1] domain if the class is initialized with normalize_kv=True argument.

Please refer to the wiki for details on using this class member.

Getter:: Gets the knot vector
Setter:: Sets the knot vector
Type:: list

load(file_name)

Loads the curve from a pickled file.

Deprecated since version 5.2.4: Use exchange.import_json() instead.

Parameters:: file_name (str) – name of the file to be loaded

property name

Object name (as a string)

Please refer to the wiki for details on using this class member.

Getter:: Gets the object name
Setter:: Sets the object name
Type:: str

normal(parpos, **kwargs)

Evaluates the normal to the tangent vector of the curve at the given parametric position(s).

Parameters:: parpos (float, list or tuple) – parametric position(s) where the evaluation will be executed
Returns:: normal vector as a tuple of the origin point and the vector components
Return type:: tuple

property opt

Dictionary for storing custom data in the current geometry object.

opt is a wrapper to a dict in key => value format, where key is string, value is any Python object. You can use opt property to store custom data inside the geometry object. For instance:

geom.opt = ["face_id", 4]  # creates "face_id" key and sets its value to an integer
geom.opt = ["contents", "data values"]  # creates "face_id" key and sets its value to a string
print(geom.opt)  # will print: {'face_id': 4, 'contents': 'data values'}

del geom.opt  # deletes the contents of the hash map
print(geom.opt)  # will print: {}

geom.opt = ["body_id", 1]  # creates "body_id" key  and sets its value to 1
geom.opt = ["body_id", 12]  # changes the value of "body_id" to 12
print(geom.opt)  # will print: {'body_id': 12}

geom.opt = ["body_id", None]  # deletes "body_id"
print(geom.opt)  # will print: {}

Please refer to the wiki for details on using this class member.

Getter:: Gets the dict
Setter:: Adds key and value pair to the dict
Deleter:: Deletes the contents of the dict

opt_get(value)

Safely query for the value from the opt property.

Parameters:: value (str) – a key in the opt property
Returns:: the corresponding value, if the key exists. None, otherwise.

property order

Order.

Defined as order = degree + 1

Please refer to the wiki for details on using this class member.

Getter:: Gets the order
Setter:: Sets the order
Type:: int

property pdimension

Parametric dimension.

Please refer to the wiki for details on using this class member.

Getter:: Gets the parametric dimension
Type:: int

property range

Domain range.

Getter:: Gets the range

property rational

Defines the rational and non-rational B-spline shapes.

Rational shapes use homogeneous coordinates which includes a weight alongside with the Cartesian coordinates. Rational B-splines are also named as NURBS (Non-uniform rational basis spline) and non-rational B-splines are sometimes named as NUBS (Non-uniform basis spline) or directly as B-splines.

Please refer to the wiki for details on using this class member.

Getter:: Returns True is the B-spline object is rational (NURBS)
Type:: bool

remove_knot(param, **kwargs)

Removes the knot and updates the control points array and the knot vector.

Keyword Arguments:

num: Number of knot removals. Default: 1

Parameters:: param (float) – knot to be removed

render(**kwargs)

Renders the curve using the visualization component

The visualization component must be set using vis property before calling this method.

Keyword Arguments:

cpcolor: sets the color of the control points polygon
evalcolor: sets the color of the curve
bboxcolor: sets the color of the bounding box
filename: saves the plot with the input name
plot: controls plot window visibility. Default: True
animate: activates animation (if supported). Default: False
extras: adds line plots to the figure. Default: None

plot argument is useful when you would like to work on the command line without any window context. If plot flag is False, this method saves the plot as an image file (.png file where possible) and disables plot window popping out. If you don’t provide a file name, the name of the image file will be pulled from the configuration class.

extras argument can be used to add extra line plots to the figure. This argument expects a list of dicts in the format described below:

[
    dict(  # line plot 1
        points=[[1, 2, 3], [4, 5, 6]],  # list of points
        name="My line Plot 1",  # name displayed on the legend
        color="red",   # color of the line plot
        size=6.5  # size of the line plot
    ),
    dict(  # line plot 2
        points=[[7, 8, 9], [10, 11, 12]],  # list of points
        name="My line Plot 2",  # name displayed on the legend
        color="navy",   # color of the line plot
        size=12.5  # size of the line plot
    )
]

Returns:: the figure object

reset(**kwargs)

Resets control points and/or evaluated points.

Keyword Arguments:

evalpts: if True, then resets evaluated points
ctrlpts if True, then resets control points

reverse(): Reverses the curve

property sample_size

Sample size.

Sample size defines the number of evaluated points to generate. It also sets the delta property.

The following figure illustrates the working principles of sample size property:

$\underbrace {\left[ {{u_{start}}, \ldots ,{u_{end}}} \right]}_{{n_{sample}}}$

Please refer to the wiki for details on using this class member.

Getter:: Gets sample size
Setter:: Sets sample size
Type:: int

save(file_name)

Saves the curve as a pickled file.

Deprecated since version 5.2.4: Use exchange.export_json() instead.

Parameters:: file_name (str) – name of the file to be saved

set_ctrlpts(ctrlpts, *args, **kwargs)

Sets control points and checks if the data is consistent.

This method is designed to provide a consistent way to set control points whether they are weighted or not. It directly sets the control points member of the class, and therefore it doesn’t return any values. The input will be an array of coordinates. If you are working in the 3-dimensional space, then your coordinates will be an array of 3 elements representing (x, y, z) coordinates.

Parameters:: ctrlpts (list) – input control points as a list of coordinates

tangent(parpos, **kwargs)

Evaluates the tangent vector of the curve at the given parametric position(s).

Parameters:: parpos (float, list or tuple) – parametric position(s) where the evaluation will be executed
Returns:: tangent vector as a tuple of the origin point and the vector components
Return type:: tuple

property type

Geometry type

Please refer to the wiki for details on using this class member.

Getter:: Gets the geometry type
Type:: str

property vis

Visualization component.

Please refer to the wiki for details on using this class member.

Getter:: Gets the visualization component
Setter:: Sets the visualization component
Type:: vis.VisAbstract

property weights

Weights.

Note

Only available for rational spline geometries. Getter return None otherwise.

Please refer to the wiki for details on using this class member.

Getter:: Gets the weights
Setter:: Sets the weights

B-Spline Surface

class geomdl.BSpline.Surface(**kwargs)

Bases: Surface

Data storage and evaluation class for B-spline (non-rational) surfaces.

This class provides the following properties:

The following code segment illustrates the usage of Surface class:

from geomdl import BSpline

# Create a BSpline surface instance (Bezier surface)
surf = BSpline.Surface()

# Set degrees
surf.degree_u = 3
surf.degree_v = 2

# Set control points
control_points = [[0, 0, 0], [0, 4, 0], [0, 8, -3],
                  [2, 0, 6], [2, 4, 0], [2, 8, 0],
                  [4, 0, 0], [4, 4, 0], [4, 8, 3],
                  [6, 0, 0], [6, 4, -3], [6, 8, 0]]
surf.set_ctrlpts(control_points, 4, 3)

# Set knot vectors
surf.knotvector_u = [0, 0, 0, 0, 1, 1, 1, 1]
surf.knotvector_v = [0, 0, 0, 1, 1, 1]

# Set evaluation delta (control the number of surface points)
surf.delta = 0.05

# Get surface points (the surface will be automatically evaluated)
surface_points = surf.evalpts

Keyword Arguments:

precision: number of decimal places to round to. Default: 18
normalize_kv: activates knot vector normalization. Default: True
find_span_func: sets knot span search implementation. Default: helpers.find_span_linear()
insert_knot_func: sets knot insertion implementation. Default: operations.insert_knot()
remove_knot_func: sets knot removal implementation. Default: operations.remove_knot()

Please refer to the abstract.Surface() documentation for more details.

add_trim(trim)

Adds a trim to the surface.

A trim is a 2-dimensional curve defined on the parametric domain of the surface. Therefore, x-coordinate of the trimming curve corresponds to u parametric direction of the surfaceand y-coordinate of the trimming curve corresponds to v parametric direction of the surface.

trims uses this method to add trims to the surface.

Parameters:: trim (abstract.Geometry) – surface trimming curve

property bbox

Bounding box.

Evaluates the bounding box and returns the minimum and maximum coordinates.

Please refer to the wiki for details on using this class member.

Getter:: Gets the bounding box
Type:: tuple

property cpsize

Number of control points in all parametric directions.

Note

This is an expert property for getting and setting control point size(s) of the geometry.

Please refer to the wiki for details on using this class member.

Getter:: Gets the number of control points
Setter:: Sets the number of control points
Type:: list

property ctrlpts

1-dimensional array of control points.

Note

The v index varies first. That is, a row of v control points for the first u value is found first. Then, the row of v control points for the next u value.

Please refer to the wiki for details on using this class member.

Getter:: Gets the control points
Setter:: Sets the control points
Type:: list

property ctrlpts2d

2-dimensional array of control points.

The getter returns a tuple of 2D control points (weighted control points + weights if NURBS) in [u][v] format. The rows of the returned tuple correspond to v-direction and the columns correspond to u-direction.

The following example can be used to traverse 2D control points:

# Create a BSpline surface
surf_bs = BSpline.Surface()

# Do degree, control points and knot vector assignments here

# Each u includes a row of v values
for u in surf_bs.ctrlpts2d:
    # Each row contains the coordinates of the control points
    for v in u:
        print(str(v))  # will be something like (1.0, 2.0, 3.0)

# Create a NURBS surface
surf_nb = NURBS.Surface()

# Do degree, weighted control points and knot vector assignments here

# Each u includes a row of v values
for u in surf_nb.ctrlpts2d:
    # Each row contains the coordinates of the weighted control points
    for v in u:
        print(str(v))  # will be something like (0.5, 1.0, 1.5, 0.5)

When using NURBS.Surface class, the output of ctrlpts2d property could be confusing since, ctrlpts always returns the unweighted control points, i.e. ctrlpts property returns 3D control points all divided by the weights and you can use weights property to access the weights vector, but ctrlpts2d returns the weighted ones plus weights as the last element. This difference is intentionally added for compatibility and interoperability purposes.

To explain this situation in a simple way;

If you need the weighted control points directly, use ctrlpts2d
If you need the control points and the weights separately, use ctrlpts and weights

Note

Please note that the setter doesn’t check for inconsistencies and using the setter is not recommended. Instead of the setter property, please use set_ctrlpts() function.

Please refer to the wiki for details on using this class member.

Getter:: Gets the control points as a 2-dimensional array in [u][v] format
Setter:: Sets the control points as a 2-dimensional array in [u][v] format
Type:: list

property ctrlpts_size

Total number of control points.

Getter:: Gets the total number of control points
Type:: int

property ctrlpts_size_u

Number of control points for the u-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets number of control points for the u-direction
Setter:: Sets number of control points for the u-direction

property ctrlpts_size_v

Number of control points for the v-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets number of control points on the v-direction
Setter:: Sets number of control points on the v-direction

property data

Returns a dict which contains the geometry data.

Please refer to the wiki for details on using this class member.

property degree

Degree for u- and v-directions

Getter:: Gets the degree
Setter:: Sets the degree
Type:: list

property degree_u

Degree for the u-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets degree for the u-direction
Setter:: Sets degree for the u-direction
Type:: int

property degree_v

Degree for the v-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets degree for the v-direction
Setter:: Sets degree for the v-direction
Type:: int

property delta

Evaluation delta for both u- and v-directions.

Evaluation delta corresponds to the step size while evaluate() function iterates on the knot vector to generate surface points. Decreasing step size results in generation of more surface points. Therefore; smaller the delta value, smoother the surface.

Please note that delta and sample_size properties correspond to the same variable with different descriptions. Therefore, setting delta will also set sample_size.

The following figure illustrates the working principles of the delta property:

$\left[{{u_{0}},{u_{start}} + \delta ,({u_{start}} + \delta ) + \delta , \ldots ,{u_{end}}} \right]$

Please refer to the wiki for details on using this class member.

Getter:: Gets evaluation delta as a tuple of values corresponding to u- and v-directions
Setter:: Sets evaluation delta for both u- and v-directions
Type:: float

property delta_u

Evaluation delta for the u-direction.

Evaluation delta corresponds to the step size while evaluate() function iterates on the knot vector to generate surface points. Decreasing step size results in generation of more surface points. Therefore; smaller the delta value, smoother the surface.

Please note that delta_u and sample_size_u properties correspond to the same variable with different descriptions. Therefore, setting delta_u will also set sample_size_u.

Please refer to the wiki for details on using this class member.

Getter:: Gets evaluation delta for the u-direction
Setter:: Sets evaluation delta for the u-direction
Type:: float

property delta_v

Evaluation delta for the v-direction.

Evaluation delta corresponds to the step size while evaluate() function iterates on the knot vector to generate surface points. Decreasing step size results in generation of more surface points. Therefore; smaller the delta value, smoother the surface.

Please note that delta_v and sample_size_v properties correspond to the same variable with different descriptions. Therefore, setting delta_v will also set sample_size_v.

Please refer to the wiki for details on using this class member.

Getter:: Gets evaluation delta for the v-direction
Setter:: Sets evaluation delta for the v-direction
Type:: float

derivatives(u, v, order=0, **kwargs)

Evaluates n-th order surface derivatives at the given (u, v) parameter pair.

SKL[0][0] will be the surface point itself
SKL[0][1] will be the 1st derivative w.r.t. v
SKL[2][1] will be the 2nd derivative w.r.t. u and 1st derivative w.r.t. v

Parameters:

u (float) – parameter on the u-direction
v (float) – parameter on the v-direction
order (integer) – derivative order

Returns:

A list SKL, where SKL[k][l] is the derivative of the surface S(u,v) w.r.t. u k times and v l times

Return type:

list

property dimension

Spatial dimension.

Spatial dimension will be automatically estimated from the first element of the control points array.

Please refer to the wiki for details on using this class member.

Getter:: Gets the spatial dimension, e.g. 2D, 3D, etc.
Type:: int

property domain

Domain.

Domain is determined using the knot vector(s).

Getter:: Gets the domain

property evalpts

Evaluated points.

Please refer to the wiki for details on using this class member.

Getter:: Gets the coordinates of the evaluated points
Type:: list

evaluate(**kwargs)

Evaluates the surface.

The evaluated points are stored in evalpts property.

Keyword arguments:

start_u: start parameter on the u-direction
stop_u: stop parameter on the u-direction
start_v: start parameter on the v-direction
stop_v: stop parameter on the v-direction

The start_u, start_v and stop_u and stop_v parameters allow evaluation of a surface segment in the range [start_u, stop_u][start_v, stop_v] i.e. the surface will also be evaluated at the stop_u and stop_v parameter values.

The following examples illustrate the usage of the keyword arguments.

# Start evaluating in range u=[0, 0.7] and v=[0.1, 1]
surf.evaluate(stop_u=0.7, start_v=0.1)

# Start evaluating in range u=[0, 1] and v=[0.1, 0.3]
surf.evaluate(start_v=0.1, stop_v=0.3)

# Get the evaluated points
surface_points = surf.evalpts

evaluate_list(param_list)

Evaluates the surface for a given list of (u, v) parameters.

Parameters:: param_list (list, tuple) – list of parameter pairs (u, v)
Returns:: evaluated surface point at the input parameter pairs
Return type:: tuple

evaluate_single(param)

Evaluates the surface at the input (u, v) parameter pair.

Parameters:: param (list, tuple) – parameter pair (u, v)
Returns:: evaluated surface point at the given parameter pair
Return type:: list

property evaluator

Evaluator instance.

Evaluators allow users to use different algorithms for B-Spline and NURBS evaluations. Please see the documentation on Evaluator classes.

Please refer to the wiki for details on using this class member.

Getter:: Gets the current Evaluator instance
Setter:: Sets the Evaluator instance
Type:: evaluators.AbstractEvaluator

property faces

Faces (triangles, quads, etc.) generated by the tessellation operation.

If the tessellation component is set to None, the result will be an empty list.

Getter:: Gets the faces

property id

Object ID (as an integer).

Please refer to the wiki for details on using this class member.

Getter:: Gets the object ID
Setter:: Sets the object ID
Type:: int

insert_knot(u=None, v=None, **kwargs)

Inserts knot(s) on the u- or v-directions

Keyword Arguments:

num_u: Number of knot insertions on the u-direction. Default: 1
num_v: Number of knot insertions on the v-direction. Default: 1

Parameters:

u (float) – knot to be inserted on the u-direction
v (float) – knot to be inserted on the v-direction

property knotvector

Knot vector for u- and v-directions

Getter:: Gets the knot vector
Setter:: Sets the knot vector
Type:: list

property knotvector_u

Knot vector for the u-direction.

The knot vector will be normalized to [0, 1] domain if the class is initialized with normalize_kv=True argument.

Please refer to the wiki for details on using this class member.

Getter:: Gets knot vector for the u-direction
Setter:: Sets knot vector for the u-direction
Type:: list

property knotvector_v

Knot vector for the v-direction.

The knot vector will be normalized to [0, 1] domain if the class is initialized with normalize_kv=True argument.

Please refer to the wiki for details on using this class member.

Getter:: Gets knot vector for the v-direction
Setter:: Sets knot vector for the v-direction
Type:: list

load(file_name)

Loads the surface from a pickled file.

Deprecated since version 5.2.4: Use exchange.import_json() instead.

Parameters:: file_name (str) – name of the file to be loaded

property name

Object name (as a string)

Please refer to the wiki for details on using this class member.

Getter:: Gets the object name
Setter:: Sets the object name
Type:: str

normal(parpos, **kwargs)

Evaluates the normal vector of the surface at the given parametric position(s).

Parameters:: parpos (list or tuple) – parametric position(s) where the evaluation will be executed
Returns:: an array containing “point” and “vector” pairs
Return type:: tuple

property opt

Dictionary for storing custom data in the current geometry object.

opt is a wrapper to a dict in key => value format, where key is string, value is any Python object. You can use opt property to store custom data inside the geometry object. For instance:

geom.opt = ["face_id", 4]  # creates "face_id" key and sets its value to an integer
geom.opt = ["contents", "data values"]  # creates "face_id" key and sets its value to a string
print(geom.opt)  # will print: {'face_id': 4, 'contents': 'data values'}

del geom.opt  # deletes the contents of the hash map
print(geom.opt)  # will print: {}

geom.opt = ["body_id", 1]  # creates "body_id" key  and sets its value to 1
geom.opt = ["body_id", 12]  # changes the value of "body_id" to 12
print(geom.opt)  # will print: {'body_id': 12}

geom.opt = ["body_id", None]  # deletes "body_id"
print(geom.opt)  # will print: {}

Please refer to the wiki for details on using this class member.

Getter:: Gets the dict
Setter:: Adds key and value pair to the dict
Deleter:: Deletes the contents of the dict

opt_get(value)

Safely query for the value from the opt property.

Parameters:: value (str) – a key in the opt property
Returns:: the corresponding value, if the key exists. None, otherwise.

property order_u

Order for the u-direction.

Defined as order = degree + 1

Please refer to the wiki for details on using this class member.

Getter:: Gets order for the u-direction
Setter:: Sets order for the u-direction
Type:: int

property order_v

Order for the v-direction.

Defined as order = degree + 1

Please refer to the wiki for details on using this class member.

Getter:: Gets surface order for the v-direction
Setter:: Sets surface order for the v-direction
Type:: int

property pdimension

Parametric dimension.

Please refer to the wiki for details on using this class member.

Getter:: Gets the parametric dimension
Type:: int

property range

Domain range.

Getter:: Gets the range

property rational

Defines the rational and non-rational B-spline shapes.

Rational shapes use homogeneous coordinates which includes a weight alongside with the Cartesian coordinates. Rational B-splines are also named as NURBS (Non-uniform rational basis spline) and non-rational B-splines are sometimes named as NUBS (Non-uniform basis spline) or directly as B-splines.

Please refer to the wiki for details on using this class member.

Getter:: Returns True is the B-spline object is rational (NURBS)
Type:: bool

remove_knot(u=None, v=None, **kwargs)

Inserts knot(s) on the u- or v-directions

Keyword Arguments:

num_u: Number of knot removals on the u-direction. Default: 1
num_v: Number of knot removals on the v-direction. Default: 1

Parameters:

u (float) – knot to be removed on the u-direction
v (float) – knot to be removed on the v-direction

render(**kwargs)

Renders the surface using the visualization component.

The visualization component must be set using vis property before calling this method.

Keyword Arguments:

cpcolor: sets the color of the control points grid
evalcolor: sets the color of the surface
trimcolor: sets the color of the trim curves
filename: saves the plot with the input name
plot: controls plot window visibility. Default: True
animate: activates animation (if supported). Default: False
extras: adds line plots to the figure. Default: None
colormap: sets the colormap of the surface

The plot argument is useful when you would like to work on the command line without any window context. If plot flag is False, this method saves the plot as an image file (.png file where possible) and disables plot window popping out. If you don’t provide a file name, the name of the image file will be pulled from the configuration class.

extras argument can be used to add extra line plots to the figure. This argument expects a list of dicts in the format described below:

[
    dict(  # line plot 1
        points=[[1, 2, 3], [4, 5, 6]],  # list of points
        name="My line Plot 1",  # name displayed on the legend
        color="red",   # color of the line plot
        size=6.5  # size of the line plot
    ),
    dict(  # line plot 2
        points=[[7, 8, 9], [10, 11, 12]],  # list of points
        name="My line Plot 2",  # name displayed on the legend
        color="navy",   # color of the line plot
        size=12.5  # size of the line plot
    )
]

Please note that colormap argument can only work with visualization classes that support colormaps. As an example, please see VisMPL.VisSurfTriangle() class documentation. This method expects a single colormap input.

Returns:: the figure object

reset(**kwargs)

Resets control points and/or evaluated points.

Keyword Arguments:

evalpts: if True, then resets evaluated points
ctrlpts if True, then resets control points

property sample_size

Sample size for both u- and v-directions.

Sample size defines the number of surface points to generate. It also sets the delta property.

The following figure illustrates the working principles of sample size property:

$\underbrace {\left[ {{u_{start}}, \ldots ,{u_{end}}} \right]}_{{n_{sample}}}$

Please refer to the wiki for details on using this class member.

Getter:: Gets sample size as a tuple of values corresponding to u- and v-directions
Setter:: Sets sample size for both u- and v-directions
Type:: int

property sample_size_u

Sample size for the u-direction.

Sample size defines the number of surface points to generate. It also sets the delta_u property.

Please refer to the wiki for details on using this class member.

Getter:: Gets sample size for the u-direction
Setter:: Sets sample size for the u-direction
Type:: int

property sample_size_v

Sample size for the v-direction.

Sample size defines the number of surface points to generate. It also sets the delta_v property.

Please refer to the wiki for details on using this class member.

Getter:: Gets sample size for the v-direction
Setter:: Sets sample size for the v-direction
Type:: int

save(file_name)

Saves the surface as a pickled file.

Deprecated since version 5.2.4: Use exchange.export_json() instead.

Parameters:: file_name (str) – name of the file to be saved

set_ctrlpts(ctrlpts, *args, **kwargs)

Sets the control points and checks if the data is consistent.

This method is designed to provide a consistent way to set control points whether they are weighted or not. It directly sets the control points member of the class, and therefore it doesn’t return any values. The input will be an array of coordinates. If you are working in the 3-dimensional space, then your coordinates will be an array of 3 elements representing (x, y, z) coordinates.

This method also generates 2D control points in [u][v] format which can be accessed via ctrlpts2d.

Note

The v index varies first. That is, a row of v control points for the first u value is found first. Then, the row of v control points for the next u value.

Parameters:: ctrlpts (list) – input control points as a list of coordinates

tangent(parpos, **kwargs)

Evaluates the tangent vectors of the surface at the given parametric position(s).

Parameters:: parpos (list or tuple) – parametric position(s) where the evaluation will be executed
Returns:: an array containing “point” and “vector”s on u- and v-directions, respectively
Return type:: tuple

tessellate(**kwargs)

Tessellates the surface.

Keyword arguments are directly passed to the tessellation component.

property tessellator

Tessellation component.

Please refer to the wiki for details on using this class member.

Getter:: Gets the tessellation component
Setter:: Sets the tessellation component

transpose(): Transposes the surface by swapping u and v parametric directions.

property trims

Curves for trimming the surface.

Surface trims are 2-dimensional curves which are introduced on the parametric space of the surfaces. Trim curves can be a spline curve, an analytic curve or a 2-dimensional freeform shape. To visualize the trimmed surfaces, you need to use a tessellator that supports trimming. The following code snippet illustrates changing the default surface tessellator to the trimmed surface tessellator, tessellate.TrimTessellate.

from geomdl import tessellate

# Assuming that "surf" variable stores the surface instance
surf.tessellator = tessellate.TrimTessellate()

In addition, using trims initialization argument of the visualization classes, trim curves can be visualized together with their underlying surfaces. Please refer to the visualization configuration class initialization arguments for more details.

Please refer to the wiki for details on using this class member.

Getter:: Gets the array of trim curves
Setter:: Sets the array of trim curves

property type

Geometry type

Please refer to the wiki for details on using this class member.

Getter:: Gets the geometry type
Type:: str

property vertices

Vertices generated by the tessellation operation.

If the tessellation component is set to None, the result will be an empty list.

Getter:: Gets the vertices

property vis

Visualization component.

Please refer to the wiki for details on using this class member.

Getter:: Gets the visualization component
Setter:: Sets the visualization component
Type:: vis.VisAbstract

property weights

Weights.

Note

Only available for rational spline geometries. Getter return None otherwise.

Please refer to the wiki for details on using this class member.

Getter:: Gets the weights
Setter:: Sets the weights

B-Spline Volume

Added in version 5.0.

class geomdl.BSpline.Volume(**kwargs)

Bases: Volume

Data storage and evaluation class for B-spline (non-rational) volumes.

This class provides the following properties:

Keyword Arguments:

precision: number of decimal places to round to. Default: 18
normalize_kv: activates knot vector normalization. Default: True
find_span_func: sets knot span search implementation. Default: helpers.find_span_linear()
insert_knot_func: sets knot insertion implementation. Default: operations.insert_knot()
remove_knot_func: sets knot removal implementation. Default: operations.remove_knot()

Please refer to the abstract.Volume() documentation for more details.

add_trim(trim)

Adds a trim to the volume.

trims uses this method to add trims to the volume.

Parameters:: trim (abstract.Surface) – trimming surface

property bbox

Bounding box.

Evaluates the bounding box and returns the minimum and maximum coordinates.

Please refer to the wiki for details on using this class member.

Getter:: Gets the bounding box
Type:: tuple

property cpsize

Number of control points in all parametric directions.

Note

This is an expert property for getting and setting control point size(s) of the geometry.

Please refer to the wiki for details on using this class member.

Getter:: Gets the number of control points
Setter:: Sets the number of control points
Type:: list

property ctrlpts

1-dimensional array of control points.

Please refer to the wiki for details on using this class member.

Getter:: Gets the control points
Setter:: Sets the control points
Type:: list

property ctrlpts_size

Total number of control points.

Getter:: Gets the total number of control points
Type:: int

property ctrlpts_size_u

Number of control points for the u-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets number of control points for the u-direction
Setter:: Sets number of control points for the u-direction

property ctrlpts_size_v

Number of control points for the v-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets number of control points for the v-direction
Setter:: Sets number of control points for the v-direction

property ctrlpts_size_w

Number of control points for the w-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets number of control points for the w-direction
Setter:: Sets number of control points for the w-direction

property data

Returns a dict which contains the geometry data.

Please refer to the wiki for details on using this class member.

property degree

Degree for u-, v- and w-directions

Getter:: Gets the degree
Setter:: Sets the degree
Type:: list

property degree_u

Degree for the u-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets degree for the u-direction
Setter:: Sets degree for the u-direction
Type:: int

property degree_v

Degree for the v-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets degree for the v-direction
Setter:: Sets degree for the v-direction
Type:: int

property degree_w

Degree for the w-direction.

Please refer to the wiki for details on using this class member.

Getter:: Gets degree for the w-direction
Setter:: Sets degree for the w-direction
Type:: int

property delta

Evaluation delta for u-, v- and w-directions.

Evaluation delta corresponds to the step size while evaluate() function iterates on the knot vector to generate surface points. Decreasing step size results in generation of more surface points. Therefore; smaller the delta value, smoother the surface.

Please note that delta and sample_size properties correspond to the same variable with different descriptions. Therefore, setting delta will also set sample_size.

The following figure illustrates the working principles of the delta property:

$\left[{{u_{0}},{u_{start}} + \delta ,({u_{start}} + \delta ) + \delta , \ldots ,{u_{end}}} \right]$

Please refer to the wiki for details on using this class member.

Getter:: Gets evaluation delta as a tuple of values corresponding to u-, v- and w-directions
Setter:: Sets evaluation delta for u-, v- and w-directions
Type:: float

property delta_u

Evaluation delta for the u-direction.

Evaluation delta corresponds to the step size while evaluate() function iterates on the knot vector to generate surface points. Decreasing step size results in generation of more surface points. Therefore; smaller the delta value, smoother the surface.

Please note that delta_u and sample_size_u properties correspond to the same variable with different descriptions. Therefore, setting delta_u will also set sample_size_u.

Please refer to the wiki for details on using this class member.

Getter:: Gets evaluation delta for the u-direction
Setter:: Sets evaluation delta for the u-direction
Type:: float

property delta_v

Evaluation delta for the v-direction.

Evaluation delta corresponds to the step size while evaluate() function iterates on the knot vector to generate surface points. Decreasing step size results in generation of more surface points. Therefore; smaller the delta value, smoother the surface.

Please note that delta_v and sample_size_v properties correspond to the same variable with different descriptions. Therefore, setting delta_v will also set sample_size_v.

Please refer to the wiki for details on using this class member.

Getter:: Gets evaluation delta for the v-direction
Setter:: Sets evaluation delta for the v-direction
Type:: float

property delta_w

Evaluation delta for the w-direction.

Evaluation delta corresponds to the step size while evaluate() function iterates on the knot vector to generate surface points. Decreasing step size results in generation of more surface points. Therefore; smaller the delta value, smoother the surface.

Please note that delta_w and sample_size_w properties correspond to the same variable with different descriptions. Therefore, setting delta_w will also set sample_size_w.

Please refer to the wiki for details on using this class member.

Getter:: Gets evaluation delta for the w-direction
Setter:: Sets evaluation delta for the w-direction
Type:: float

property dimension

Spatial dimension.

Spatial dimension will be automatically estimated from the first element of the control points array.

Please refer to the wiki for details on using this class member.

Getter:: Gets the spatial dimension, e.g. 2D, 3D, etc.
Type:: int

property domain

Domain.

Domain is determined using the knot vector(s).

Getter:: Gets the domain

property evalpts

Evaluated points.

Please refer to the wiki for details on using this class member.

Getter:: Gets the coordinates of the evaluated points
Type:: list

evaluate(**kwargs)

Evaluates the volume.

The evaluated points are stored in evalpts property.

Keyword arguments:

start_u: start parameter on the u-direction
stop_u: stop parameter on the u-direction
start_v: start parameter on the v-direction
stop_v: stop parameter on the v-direction
start_w: start parameter on the w-direction
stop_w: stop parameter on the w-direction

evaluate_list(param_list)

Evaluates the volume for a given list of (u, v, w) parameters.

Parameters:: param_list (list, tuple) – list of parameters in format (u, v, w)
Returns:: evaluated surface point at the input parameter pairs
Return type:: tuple

evaluate_single(param)

Evaluates the volume at the input (u, v, w) parameter.

Parameters:: param (list, tuple) – parameter (u, v, w)
Returns:: evaluated surface point at the given parameter pair
Return type:: list

property evaluator

Evaluator instance.

Evaluators allow users to use different algorithms for B-Spline and NURBS evaluations. Please see the documentation on Evaluator classes.

Please refer to the wiki for details on using this class member.

Getter:: Gets the current Evaluator instance
Setter:: Sets the Evaluator instance
Type:: evaluators.AbstractEvaluator

property id

Object ID (as an integer).

Please refer to the wiki for details on using this class member.

Getter:: Gets the object ID
Setter:: Sets the object ID
Type:: int

insert_knot(u=None, v=None, w=None, **kwargs)

Inserts knot(s) on the u-, v- and w-directions

Keyword Arguments:

num_u: Number of knot insertions on the u-direction. Default: 1
num_v: Number of knot insertions on the v-direction. Default: 1
num_w: Number of knot insertions on the w-direction. Default: 1

Parameters:

u (float) – knot to be inserted on the u-direction
v (float) – knot to be inserted on the v-direction
w (float) – knot to be inserted on the w-direction

property knotvector

Knot vector for u-, v- and w-directions

Getter:: Gets the knot vector
Setter:: Sets the knot vector
Type:: list

property knotvector_u

Knot vector for the u-direction.

The knot vector will be normalized to [0, 1] domain if the class is initialized with normalize_kv=True argument.

Please refer to the wiki for details on using this class member.

Getter:: Gets knot vector for the u-direction
Setter:: Sets knot vector for the u-direction
Type:: list

property knotvector_v

Knot vector for the v-direction.

The knot vector will be normalized to [0, 1] domain if the class is initialized with normalize_kv=True argument.

Please refer to the wiki for details on using this class member.

Getter:: Gets knot vector for the v-direction
Setter:: Sets knot vector for the v-direction
Type:: list

property knotvector_w

Knot vector for the w-direction.

The knot vector will be normalized to [0, 1] domain if the class is initialized with normalize_kv=True argument.

Please refer to the wiki for details on using this class member.

Getter:: Gets knot vector for the w-direction
Setter:: Sets knot vector for the w-direction
Type:: list

load(file_name)

Loads the volume from a pickled file.

Deprecated since version 5.2.4: Use exchange.import_json() instead.

Parameters:: file_name (str) – name of the file to be loaded

property name

Object name (as a string)

Please refer to the wiki for details on using this class member.

Getter:: Gets the object name
Setter:: Sets the object name
Type:: str

property opt

Dictionary for storing custom data in the current geometry object.

opt is a wrapper to a dict in key => value format, where key is string, value is any Python object. You can use opt property to store custom data inside the geometry object. For instance:

geom.opt = ["face_id", 4]  # creates "face_id" key and sets its value to an integer
geom.opt = ["contents", "data values"]  # creates "face_id" key and sets its value to a string
print(geom.opt)  # will print: {'face_id': 4, 'contents': 'data values'}

del geom.opt  # deletes the contents of the hash map
print(geom.opt)  # will print: {}

geom.opt = ["body_id", 1]  # creates "body_id" key  and sets its value to 1
geom.opt = ["body_id", 12]  # changes the value of "body_id" to 12
print(geom.opt)  # will print: {'body_id': 12}

geom.opt = ["body_id", None]  # deletes "body_id"
print(geom.opt)  # will print: {}

Please refer to the wiki for details on using this class member.

Getter:: Gets the dict
Setter:: Adds key and value pair to the dict
Deleter:: Deletes the contents of the dict

opt_get(value)

Safely query for the value from the opt property.

Parameters:: value (str) – a key in the opt property
Returns:: the corresponding value, if the key exists. None, otherwise.

property order_u

Order for the u-direction.

Defined as order = degree + 1

Please refer to the wiki for details on using this class member.

Getter:: Gets the surface order for u-direction
Setter:: Sets the surface order for u-direction
Type:: int

property order_v

Order for the v-direction.

Defined as order = degree + 1

Please refer to the wiki for details on using this class member.

Getter:: Gets the surface order for v-direction
Setter:: Sets the surface order for v-direction
Type:: int

property order_w

Order for the w-direction.

Defined as order = degree + 1

Please refer to the wiki for details on using this class member.

Getter:: Gets the surface order for v-direction
Setter:: Sets the surface order for v-direction
Type:: int

property pdimension

Parametric dimension.

Please refer to the wiki for details on using this class member.

Getter:: Gets the parametric dimension
Type:: int

property range

Domain range.

Getter:: Gets the range

property rational

Defines the rational and non-rational B-spline shapes.

Rational shapes use homogeneous coordinates which includes a weight alongside with the Cartesian coordinates. Rational B-splines are also named as NURBS (Non-uniform rational basis spline) and non-rational B-splines are sometimes named as NUBS (Non-uniform basis spline) or directly as B-splines.

Please refer to the wiki for details on using this class member.

Getter:: Returns True is the B-spline object is rational (NURBS)
Type:: bool

remove_knot(u=None, v=None, w=None, **kwargs)

Inserts knot(s) on the u-, v- and w-directions

Keyword Arguments:

num_u: Number of knot removals on the u-direction. Default: 1
num_v: Number of knot removals on the v-direction. Default: 1
num_w: Number of knot removals on the w-direction. Default: 1

Parameters:

u (float) – knot to be removed on the u-direction
v (float) – knot to be removed on the v-direction
w (float) – knot to be removed on the w-direction

render(**kwargs)

Renders the volume using the visualization component.

The visualization component must be set using vis property before calling this method.

Keyword Arguments:

cpcolor: sets the color of the control points
evalcolor: sets the color of the volume
filename: saves the plot with the input name
plot: controls plot window visibility. Default: True
animate: activates animation (if supported). Default: False
grid_size: grid size for voxelization. Default: (8, 8, 8)
use_cubes: use cube voxels instead of cuboid ones. Default: False
num_procs: number of concurrent processes for voxelization. Default: 1

The plot argument is useful when you would like to work on the command line without any window context. If plot flag is False, this method saves the plot as an image file (.png file where possible) and disables plot window popping out. If you don’t provide a file name, the name of the image file will be pulled from the configuration class.

extras argument can be used to add extra line plots to the figure. This argument expects a list of dicts in the format described below:

[
    dict(  # line plot 1
        points=[[1, 2, 3], [4, 5, 6]],  # list of points
        name="My line Plot 1",  # name displayed on the legend
        color="red",   # color of the line plot
        size=6.5  # size of the line plot
    ),
    dict(  # line plot 2
        points=[[7, 8, 9], [10, 11, 12]],  # list of points
        name="My line Plot 2",  # name displayed on the legend
        color="navy",   # color of the line plot
        size=12.5  # size of the line plot
    )
]

Returns:: the figure object

reset(**kwargs)

Resets control points and/or evaluated points.

Keyword Arguments:

evalpts: if True, then resets evaluated points
ctrlpts if True, then resets control points

property sample_size

Sample size for both u- and v-directions.

Sample size defines the number of surface points to generate. It also sets the delta property.

The following figure illustrates the working principles of sample size property:

$\underbrace {\left[ {{u_{start}}, \ldots ,{u_{end}}} \right]}_{{n_{sample}}}$

Please refer to the wiki for details on using this class member.

Getter:: Gets sample size as a tuple of values corresponding to u-, v- and w-directions
Setter:: Sets sample size value for both u-, v- and w-directions
Type:: int

property sample_size_u

Sample size for the u-direction.

Sample size defines the number of evaluated points to generate. It also sets the delta_u property.

Please refer to the wiki for details on using this class member.

Getter:: Gets sample size for the u-direction
Setter:: Sets sample size for the u-direction
Type:: int

property sample_size_v

Sample size for the v-direction.

Sample size defines the number of evaluated points to generate. It also sets the delta_v property.

Please refer to the wiki for details on using this class member.

Getter:: Gets sample size for the v-direction
Setter:: Sets sample size for the v-direction
Type:: int

property sample_size_w

Sample size for the w-direction.

Sample size defines the number of evaluated points to generate. It also sets the delta_w property.

Please refer to the wiki for details on using this class member.

Getter:: Gets sample size for the w-direction
Setter:: Sets sample size for the w-direction
Type:: int

save(file_name)

Saves the volume as a pickled file.

Deprecated since version 5.2.4: Use exchange.export_json() instead.

Parameters:: file_name (str) – name of the file to be saved

set_ctrlpts(ctrlpts, *args, **kwargs)

Sets the control points and checks if the data is consistent.

This method is designed to provide a consistent way to set control points whether they are weighted or not. It directly sets the control points member of the class, and therefore it doesn’t return any values. The input will be an array of coordinates. If you are working in the 3-dimensional space, then your coordinates will be an array of 3 elements representing (x, y, z) coordinates.

Parameters:

ctrlpts (list) – input control points as a list of coordinates
args (tuple[int, int, int]) – number of control points corresponding to each parametric dimension

property trims

Trimming surfaces.

Please refer to the wiki for details on using this class member.

Getter:: Gets the array of trim surfaces
Setter:: Sets the array of trim surfaces

property type

Geometry type

Please refer to the wiki for details on using this class member.

Getter:: Gets the geometry type
Type:: str

property vis

Visualization component.

Please refer to the wiki for details on using this class member.

Getter:: Gets the visualization component
Setter:: Sets the visualization component
Type:: vis.VisAbstract

property weights

Weights.

Note

Only available for rational spline geometries. Getter return None otherwise.

Please refer to the wiki for details on using this class member.

Getter:: Gets the weights
Setter:: Sets the weights