Converting Curves

This task explains how to process geometry for a more efficient data management.
Each CAD system developed today, manages the geometry produced through their own set of tolerances and approximation algorithms. As a result of the approximations used in other CAD systems, it becomes critical on how geometry is created and managed when mixing this data within ISD. Today this data management process involves a lot of manual work using commands such as Conversion, Smoothing, Matching.

To address the data management process in a more efficient manner, ISD commands must be designed in a way that they can handle data coming from everywhere.

Within the Class A process, the more traditional approach for users is to obtain geometry output of a maximum order 7 and by having less segments and with a minimum Deviation from the original Input geometry. As this is not always possible users prefer to have better control over the output.

  1. Click the Curve Conversion icon .
    The Curve Conversion dialog box opens.

You can define the following options:
  • Element: Specifies the curves to be processed.
  Options tab
 
  • Approximation: The approximation options can be deactivated. This way, you can e. g. create curves from surface edges without approximation.
  • Enable Cell Fusion:
    • OFF: Each cell of a Domain will be approximated separately.
      The Cell Fusion options are not available.
    • ON: All adjacent cells of a domain whose transition quality among each other corresponds at least the value specified in Continuity, are approximated as one entity (segmentation of the domain in continuity ranges).
      The Segmentation will be applied to each continuity range.
      The transition parameters will be used as preferential parameters for further processing with the settings on the Approximation tab.
  • Cell Fusion: The Cell Fusion options are only available if Enable Cell Fusion is activaed.
    • Continuity: The cells are only merged if at least the specified continuity is kept.
      To keep the number of segments as low as possible, when using G0 continuity, the tolerance will not be considered when approximating, independent from the approximation parameters set.
    • Keep Input Cell Structure: The geometry resulting from the approximation will be re-broken at the transitions after the approximation operation.
  See Approximation tab
  See Output tab
  Click onto the button 'More Info' to display deviations and output results.
 
  • Display: Depending on the options selected, values are displayed in the graphics area.
  • Deviation:
    • Max., Min.: Shows the minimum and/or maximum deviation between the input element and the resulting output geometry, e. g. between a guide curve (input) and the resulting surface boundary (output).
      Depending on the result you can change parameters and options to improve the resulting geometry.
  • U+V: Display of the UV vectors of curves and surfaces.
  • Output Result: See Output Result