Operations on Surfaces and Primitives

The tools explained below have been developed to assist you in finding and (optionally) fix defects or weak spots in imported geometry.

Analyze

The analysis function is designed to be used to report geometric gaps within connected surface meshes. Gaps that are bigger than the overall model tolerance are reported as surface incidents. These incidents are added to the analyzed primitive and classified as warnings and errors. Gaps slightly bigger than the overall surface tolerance are classified as warnings, and bigger gaps as errors. A surface incident can be interpreted as a potential risk for problems later on when a surface is used for modelling.

Combine

The combine function combines all primitives that belong to a hull surface into single primitive. This is necessary if the surface includes more that one primitive, only the first primitive is used when the hull surface is released to a design project.

Intersect Surface

The command intersect surface is used to create curves by intersecting the model by one or more planes. Created curves are stored together with the intersected model and named by the curve prefix, curve type and the major coordinate value.

• Select the command Intersect Surface and fill in the following fields in the shown dialog:

  • Curve prefix - The first part of the curve names

  • Starting point - A point in the first intersecting plane.

  • Direction and distance - The normal vector to the intersecting planes. The length of the vector is used as the distance between successive intersection planes.

  • Ending point - New intersection curves are created as long as the ending point is in front of the current intersection plane.

Mirror

The mirror function creates a new model by combining the original model with the same model mirrored in the centerline. The original model is not allowed to extend over the centerline.

Optimize

The optimize function can be used to increase the quality of a model. Planar faces are combined and some degenerated surfaces are replaced by surfaces that are less likely to cause problems later on.

Restrict

The restrict function remove all portions of a model that are outside a given axel aligned box.

Sew

The sew function provides a mechanism for sewing topologically disjoint but geometrically adjacent faces together. The overall primitive tolerance may be increased when faces are combined together.

Compare Surfaces

This function can be used to compare a surface with another, by calculating the distance between the surface and a number of sample points. These sample points can be created from another surface or imported from an external file created by a tool in TRIBON M3. Sample points that diverge more than the intersection tolerance, normally 0.5 mm, are added to a new folder in the model view and to a report that is displayed in the message window. It is easy to get an overview of the diverging sample points by dragging the created folder to the graphics view. Diverging points are displayed by the sample point, the closest point on the surface, and a line whose length is propositional to the distance between the two points. The colour of the line reflects the deviating distance range the sample point belongs to.

Two imported surfaces can be compared by selecting two surfaces from the Hull Surfaces folder and then the Compare Surface function from the right-click menu. A dialog is then displayed that allows you to change the region to compare and the density of the sample points. Sample points are obtained from the first selected and compared with the second selected surface.

It is also possible to compare an imported surface with sample points coming from an external file by selecting a single surface and then the Surface Compare function from the right-click menu. The external file, containing the sample points, can be created by a new tool in TRIBON M3 that intersects a variant of the surface by a number of X- and Z- planes. The resulting intersection curves are then added to the file as a number of sample points on each curve. For more information, see Appendices.

Combine Curves - from Menu

This menu option will combine curves that have ends that are closer than 10 mm from each other, if the distance is greater than 10 mm the operation will fail.

Connect Curves - from Toolbar

Connect curves as preparation for use in Lines/PACE, connect curves with a line segment. When intersecting surfaces, the result may be several curve branches. For principal plane curves Lines/PACE stores these as curves of different type, named by its position. To have curves with several branches these have to be connected. Connect curve will connect curve ends with a straight line between the ends that are closest together, when the outcome is ambiguous the gap between the ends closest to selection points will be connected.