Operator Reference
select_points_object_model_3d (Operator)
select_points_object_model_3d — Apply a threshold to an attribute of 3D object models.
Signature
select_points_object_model_3d( : : ObjectModel3D, Attrib, MinValue, MaxValue : ObjectModel3DThresholded)
Description
select_points_object_model_3d selects points of the 3D object
model ObjectModel3D according to the attributes and thresholds
passed in Attrib, MinValue, and MaxValue
respectively.
The selected points are returned in the 3D object model
ObjectModel3DThresholded.
All attributes that are connected with the points
(e.g., polygons or triangles) are adapted in such a way that there is
no reference to the removed points left.
Attrib can either contain a tuple of numbers that has the same
length as ObjectModel3D has points, or a list of attribute
names on which the thresholds are applied.
If Attrib contains a tuple of numbers, exactly one number must
be passed in both MinValue and MaxValue.
All points for which the corresponding entry in Attrib is between
the two thresholds are added to the output 3D object model
ObjectModel3DThresholded.
Otherwise, Attrib can contain a list of attribute names that
refer to properties of the 3D object model ObjectModel3D.
All points, for which the value stored in the attribute Attrib
is inside the interval specified in MinValue and MaxValue
are stored in the output 3D object model.
MinValue and MaxValue must contain exactly as many
values as Attrib.
If Attrib contains multiple values, only those points are stored
in the output 3D object model that fulfill all the criteria.
Depending on the properties of ObjectModel3D, the following
values are possible for Attrib:
The following attributes are available:
- 'point_coord_x':
The x-coordinates of the set of 3D points.
- 'point_coord_y':
The y-coordinates of the set of 3D points.
- 'point_coord_z':
The z-coordinates of the set of 3D points.
- 'point_normal_x':
The x-components of the 3D point normals of the set of 3D points.
- 'point_normal_y':
The y-components of the 3D point normals of the set of 3D points.
- 'point_normal_z':
The z-components of the 3D point normals of the set of 3D points.
- 'mapping_row':
The row-components of the 2D mapping of the set of 3D points.
- 'mapping_col':
The column-components of the 2D mapping of the set of 3D points.
- 'neighbor_distance':
- 'neighbor_distance N':
The distance of the N-th nearest point. N must be a positive integer and is by default 25. For every point, all other points are sorted according to their distance and the distance of the N-th point is used.
- 'num_neighbors X':
The number of neighbors within a distance of at most X. It can be used to remove sparsely populated parts of the 3D object model, such as outliers or points that are created by smoothing between 3D surfaces.
- 'num_neighbors_fast X':
The approximate number of neighbors within a distance of at most X. The distances are approximated using voxels, leading to a faster processing compared to 'num_neighbors'.
- Extended attribute:
Enter the name of an extended attribute of the type 'vertices' and the selection will be applied based on the values of the extended attribute.
Execution Information
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Automatically parallelized on internal data level.
Parameters
ObjectModel3D (input_control) object_model_3d(-array) → (handle)
Handle of the 3D object models.
Attrib (input_control) string(-array) → (string)
Attributes the threshold is applied to.
Default: 'point_coord_z'
List of values: 'mapping_col', 'mapping_row', 'neighbor_distance', 'num_neighbors', 'num_neighbors_fast', 'point_coord_x', 'point_coord_y', 'point_coord_z', 'point_normal_x', 'point_normal_y', 'point_normal_z'
MinValue (input_control) number(-array) → (real / integer)
Minimum value for the attributes specified by
Attrib.
Default: 0.5
MaxValue (input_control) number(-array) → (real / integer)
Maximum value for the attributes specified
by Attrib.
Default: 1.0
ObjectModel3DThresholded (output_control) object_model_3d(-array) → (handle)
Handle of the reduced 3D object models.
Example (HDevelop)
gen_object_model_3d_from_points (rand(100), rand(100),\
rand(100), ObjectModel3D)
select_points_object_model_3d (ObjectModel3D, 'point_coord_z',\
0.5, 1, ObjectModel3DThresholded)
get_object_model_3d_params (ObjectModel3DThresholded, 'num_points',\
NumPoints)
Result
select_points_object_model_3d returns 2 (
H_MSG_TRUE)
if all parameters
are correct. If necessary, an exception is raised.
If the required points are missing in the object model, i.e., an empty
object model is passed, the error 9515 is raised.
Possible Predecessors
read_object_model_3d,
xyz_to_object_model_3d
Possible Successors
connection_object_model_3d,
project_object_model_3d,
object_model_3d_to_xyz
See also
connection_object_model_3d,
reduce_object_model_3d_by_view
Module
3D Metrology