volume_object_model_3d_relative_to_planeT_volume_object_model_3d_relative_to_planeVolumeObjectModel3dRelativeToPlaneVolumeObjectModel3dRelativeToPlane (Operator)

Name

volume_object_model_3d_relative_to_planeT_volume_object_model_3d_relative_to_planeVolumeObjectModel3dRelativeToPlaneVolumeObjectModel3dRelativeToPlane — Calculate the volume of a 3D object model.

Signature

Description

volume_object_model_3d_relative_to_planevolume_object_model_3d_relative_to_planeVolumeObjectModel3dRelativeToPlaneVolumeObjectModel3dRelativeToPlaneVolumeObjectModel3dRelativeToPlane calculates the volume under the faces of a 3D object model relative to a plane. The plane is defined by the x-y plane of the pose given in PlanePlanePlanePlaneplane.

For ObjectModel3DObjectModel3DObjectModel3DObjectModel3DobjectModel3D, a triangulation or a list of polygons must be available. With default settings, if the mesh is watertight and ordered, the operator calculates the actual volume of the 3D object model. To also cover cases where the mesh is not closed or the faces are not ordered consistently, the calculation of the volume can be influenced with the parameters ModeModeModeModemode and UseFaceOrientationUseFaceOrientationUseFaceOrientationUseFaceOrientationuseFaceOrientation.

How the volume is calculated:

First, the operator calculates the volume of the prisms that are constructed by projecting each face onto the plane.

The individual volumes of the prisms can be positive or negative depending on the orientation of the face (away or towards the plane) or the location of the face (above or below the plane). This can be controlled with the parameter UseFaceOrientationUseFaceOrientationUseFaceOrientationUseFaceOrientationuseFaceOrientation.

After that, the volumes of the prisms are added up depending on the parameter ModeModeModeModemode.

The volume returned in VolumeVolumeVolumeVolumevolume is the absolute value of the calculated sum.

How to set the parameters:

ModeModeModeModemode can be set to the following options:

'signed' (default)

The volumes above and below the plane are added.

'unsigned'

The volume below the plane is subtracted from the volume above the plane.

'positive'

Only faces above the plane are taken into account.

'negative'

Only faces below the plane are taken into account.

UseFaceOrientationUseFaceOrientationUseFaceOrientationUseFaceOrientationuseFaceOrientation can be set to the following options:

'true' (default)

Use the orientation of the faces relative to the plane. A face points away from the plane if the corner points are ordered clockwise when viewed from the plane. The volume under a face is considered positive if the orientation of the face is away from the plane. In contrast, it is considered negative if the orientation of the face is towards the plane.

'false'

The volume under a face is considered positive if the face is located above the plane. In contrast, it is considered negative if the face is located below the plane.

For example, with the default combination (ModeModeModeModemode: 'signed'"signed""signed""signed""signed", UseFaceOrientationUseFaceOrientationUseFaceOrientationUseFaceOrientationuseFaceOrientation: 'true'"true""true""true""true"), you can approximate the real volume of a closed object. In this case, the PlanePlanePlanePlaneplane is still required, but does not change the resulting volume.

Attention

The calculation of the volume might be numerically unstable in case of a large distance between the plane and the object (approx. distance > 10000 times the object diameter).

Execution Information

• Multithreading type: reentrant (runs in parallel with non-exclusive operators).
• Multithreading scope: global (may be called from any thread).
• Processed without parallelization.

Parameters

Example (HDevelop)

gen_box_object_model_3d ([0,0,0,0,0,0,0],3,2,1, ObjectModel3D)
convex_hull_object_model_3d (ObjectModel3D, ObjectModel3DConvexHull)
volume_object_model_3d_relative_to_plane (ObjectModel3DConvexHull,\
                                          [0,0,0,0,0,0,0], 'signed',\
                                          'true', Volume)

Result

volume_object_model_3d_relative_to_planevolume_object_model_3d_relative_to_planeVolumeObjectModel3dRelativeToPlaneVolumeObjectModel3dRelativeToPlaneVolumeObjectModel3dRelativeToPlane returns 2 (H_MSG_TRUE) if all parameters are correct. If necessary, an exception is raised.

Possible Predecessors

read_object_model_3dread_object_model_3dReadObjectModel3dReadObjectModel3dReadObjectModel3d, xyz_to_object_model_3dxyz_to_object_model_3dXyzToObjectModel3dXyzToObjectModel3dXyzToObjectModel3d, select_points_object_model_3dselect_points_object_model_3dSelectPointsObjectModel3dSelectPointsObjectModel3dSelectPointsObjectModel3d

Possible Successors

project_object_model_3dproject_object_model_3dProjectObjectModel3dProjectObjectModel3dProjectObjectModel3d, object_model_3d_to_xyzobject_model_3d_to_xyzObjectModel3dToXyzObjectModel3dToXyzObjectModel3dToXyz

See also

area_object_model_3darea_object_model_3dAreaObjectModel3dAreaObjectModel3dAreaObjectModel3d

Module

3D Metrology