Component:Intersectors

From DocR21

(Redirected from Intersectors)
Jump to: navigation, search


All Intersectors Articles | C++ APIs | Scheme Extensions | Global Options
edit  

Intersectors Component


The Intersectors Component (INTR) determines intersections between geometric elements by finding the points or intervals at which curves and surfaces meet. These functions are part of the Model Analysis functionality of ACIS.

Intersectors are implemented in low-level C++ classes that are not intended to be accessed directly by applications. They can be thought of as virtual methods of Booleans. When the Boolean operations are used properly, they invoke the correct Intersector methods.

Note: Reference material is provided on the Intersector classes because they are visible in the header files. Unpredictable results can occur when these Intersector classes are used directly by applications.



edit  

Intersectors Operations


Intersection algorithms support curve-curve intersections (CCI), curve-surface intersections (CSI), surface-surface intersections (SSI), and curve-curve intersections on a surface (CCS). These algorithms are known as intersectors.

Operation Description
Curve-Curve Intersection

The curve-curve intersection algorithm is implemented to find points or intervals where two curves meet or approach one another within a specified tolerance.

Curve-Surface Intersection

The curve-surface intersection algorithm can:

  • Intersect implicit curves and surfaces.
  • Handle the intersection between a parametric curve and a singular surface when the singularity is due to the degeneracy of the surface boundary to a single point.
Surface-Surface Intersection

The surface-surface intersection algorithm can:

  • Handle the intersection between parametric surfaces, either of which can be a singular surface due to the degeneracy of the surface boundary to a single point.
  • Calculate surface silhouette curves for any ACIS surfaces, including singular ones.
  • Accept help points in the exploration stage, which enable the intersection of implicit surfaces.
  • Produce the intersections between two offset surfaces, given a start and an end point. These intersections can then be used to calculate the spline curve during blending.
Curve-Curve Intersection on Surface

The curve-curve intersection on a surface (CCS) algorithm was introduced to improve the performance of curve-curve intersections. In many cases, the two curves being intersected are known to lie on the same surface. However, the CCI algorithm, which is generally used to intersect two curves, does not use this information. The CCS algorithm receives as input: a surface, two pcurves and the two curves to be intersected. Provided the two pcurves are an accurate representation (in the surface's parameter space) of the curves to be intersected, the CCS will try to use this information to improve the performance of the intersection computation.

Curve Self-Intersection

The curve self-intersection algorithm determines positions or intervals where a CURVE or EDGE intersects itself.


edit  

What's New in Intersectors


No interface changes for ACIS R21.



edit  

Intersectors Topics


Options

There are some global options that affect the behavior of Intersectors operations. Refer to Intersectors global options.

Journaling

Journaling is available for Intersectors through the standard ACIS options journaling mechanism.

Versioning

Main article: Versioning


Versioning is available for Intersectors through the standard ACIS options versioning mechanism.

Error Codes

Upon failure of an Intersectors API, error codes will be returned that explain the failure and suggest possible actions for correction.



edit  

See Also

Personal tools
Live