simplify_object_model_3d
— Simplify a triangulated 3D object model.
simplify_object_model_3d( : : ObjectModel3D, Method, Amount, GenParamName, GenParamValue : SimplifiedObjectModel3D)
simplify_object_model_3d
simplifies the triangulated 3D object model
ObjectModel3D
by removing model points and
returns the result in SimplifiedObjectModel3D
. Note that in
contrast to sample_object_model_3d
points are removed
such that the original geometry of the object model is represented as good
as possible. Typically, this means that edges are preserved while the
point density within smooth parts is reduced.
This might be helpful, for example, to speed up subsequent operator calls
by using a 3D object model of reduced complexity.
The triangulation of the input 3D object model is preserved as opposed to
the operator sample_object_model_3d
, which samples surfaces to
equidistant unconnected 3D points.
Currently, the operator offers only a single simplification method
('preserve_point_coordintates' ), which can be set in
Method
. This method ensures that the points in the
simplified object model SimplifiedObjectModel3D
have the same
coordinates as the respective points in the input object model
ObjectModel3D
.
simplify_object_model_3d
only works for triangulated object models.
Whether an object model contains a triangulation can be queried with
get_object_model_3d_params
(GenParamName
='has_triangles'
). Object models that
do not contain a triangulation must be triangulated beforehand, e.g., by
using triangulate_object_model_3d
or prepare_object_model_3d
(Purpose
='segmentation'
).
The degree of simplification can be set with Amount
. By default,
Amount
specifies the percentage of points of the input object
model that should be contained in the output object model. Thus, the
smaller the value of Amount
in this case is chosen the
stronger the object model will be simplified.
Alternatively, the meaning of the parameter Amount
can be
modified. For this, the generic parameter 'amount_type' can
be set to one of the following values:
'percentage_remaining' Amount
specifies the percentage of points
(default) of the input object model that should be contained
in the output object model.
Range of values: [0.0 ... 100.0]
'percentage_to_remove' Amount
specifies the percentage of points
of the input object model that should be removed.
Range of values: [0.0 ... 100.0]
'num_points_remaining' Amount
specifies the number of points
of the input object model that should be contained
in the output object model.
Range of values:
[0 ... number of points in the input object model]
'num_points_to_remove' Amount
specifies the number of points
of the input object model that should be removed.
Range of values:
[0 ... number of points in the input object model]
Sometimes triangular meshes flip during the simplification, i.e., the
direction of their normal vectors changes by 180 degrees. This
especially happens for artificially created CAD models that consist of
planar parts. To avoid this flipping, the generic
parameter 'avoid_triangle_flips' can be set to 'true'
(the default is 'false' ). Note that in this case, the run-time of
simplify_object_model_3d
will increase.
Note that multiple calls of simplify_object_model_3d
with a
lower degree of simplification might result in a different simplified
object model compared to a single call with a higher degree of
simplification. Also note that isolated (i.e., non-triangulated) points
will be removed. This might result in a number of points in
SimplifiedObjectModel3D
that slightly deviates from the degree of
simplification that is specified in Amount
.
ObjectModel3D
(input_control) object_model_3d(-array) →
(handle)
Handle of the 3D object model that should be simplified.
Method
(input_control) string →
(string)
Method that should be used for simplification.
Default value: 'preserve_point_coordinates'
List of values: 'preserve_point_coordinates'
Amount
(input_control) number →
(real / integer)
Degree of simplification (default: percentage of remaining model points).
GenParamName
(input_control) attribute.name-array →
(string)
Names of the generic parameters.
Default value: []
List of values: 'amount_type' , 'avoid_triangle_flips'
GenParamValue
(input_control) attribute.value-array →
(string / real)
Values of the generic parameters.
Default value: []
Suggested values: 'percentage_remaining' , 'percentage_to_remove' , 'num_points_remaining' , 'num_points_to_remove' , 'true' , 'false'
SimplifiedObjectModel3D
(output_control) object_model_3d(-array) →
(handle)
Handle of the simplified 3D object model.
read_object_model_3d ('mvtec_bunny.om3', 'm', [], [], ObjectModel3D, Status) visualize_object_model_3d (WindowHandle, ObjectModel3D, [], [], [], [], \ [], [], [], Pose) simplify_object_model_3d (ObjectModel3D, 'preserve_point_coordinates', \ 5.0, 'amount_type', 'percentage_remaining', \ SimplifiedObjectModel3D) visualize_object_model_3d (WindowHandle, SimplifiedObjectModel3D, [], \ Pose, [], [], [], [], [], Pose)
simplify_object_model_3d
returns 2 (H_MSG_TRUE) if all parameters are
correct. If necessary, an exception is raised.
prepare_object_model_3d
,
read_object_model_3d
,
triangulate_object_model_3d
,
xyz_to_object_model_3d
disp_object_model_3d
,
smallest_bounding_box_object_model_3d
sample_object_model_3d
,
smooth_object_model_3d
Michael Garland, Paul S. Heckbert: Surface Simplification Using Quadric Error Metrics, Proceedings of the 24th Annual Conference on Computer Graphics and Interactive Techniques (SIGGRAPH '97), 209-216, ACM Press, 1997
3D Metrology