Analyzing Surfacic Curvature

You can assess the curvature of a surface by performing a surfacic curvature analysis.

Before you begin:
  • Open an existing 3D shape.
  • Set discretization to a maximum: Select Tools > Options > General > Display > Performance tab, select Fixed in the 3D Accuracy area and enter a value of 0.01.
  • Disable highlight of geometry selection: Select Tools > Options > General > Display > Navigation tab, clear the Highlight faces and edges check box in the Selection area.
  • Set the visualization mode: Select View > Render Style > Shading With Edges.
  • Do one or both of the following:
    • Allow visualization of the analysis results on a selected element: Select View > Render Style > Customize View and then select Material in the View Mode Customization dialog box.
    • Select Tools > Options > Shape > FreeStyle > General tab and then select the No warning message if material mode is not ON check box in the Mapping Analysis option area.

  1. Click Surfacic Curvature Analysis in the Shape Analysis toolbar (Draft sub-toolbar).

    The Surfacic curvature dialog box appears.



    The Surfacic Curvature Analysis.x color scale dialog box also appears.

  2. In the Type area, select Gaussian and in the Display Options area, select Color Scale check box.

  3. Click a surface.

    The surface is painted according to the color scale in the dialog box.

  4. Adjust the color scale: In the Surfacic Curvature Analysis.x color scale dialog box, click Use Min Max.


    • The maximum and minimum values in the dialog box are set according to the values detected on the surface.
    • The analysis colors are updated to match the color scale in the dialog box.


  5. Show gaussian curvature information on all parts of the surface:

    1. In the Display Options area, select the On The Fly check box.
    2. Move the pointer over the surface.

    At the position of the pointer, the following information is displayed:

    • The local gaussian value of the curvature (Gaussian is selected in the Type area of the dialog box).
    • The direction of the maximum curvature.
    • The direction of the minimum curvature.


  6. Show minimum/maximum/mean curvature information on all parts of the surface:

    1. In the Type area, select Minimum, Maximum or Mean.
    2. Move the pointer over the surface.

    At the position of the pointer, the following information is displayed:

    • The local minimum, maximum or mean value of the curvature (according to your selection in the dialog box).
    • The local radius of curvature or mean radius of curvature (according to your selection in the dialog box).
    • The direction of the maximum curvature.
    • The direction of the minimum curvature.


    Important: The color scale does not change when you switch from one analysis type to another analysis type, or to another element. This facilitates comparison of curvature because each analysis or element can be viewed using the same reference colors and values.

  7. Show the position of the maximum and minimum values:

    1. In the Display Options area, clear the On The Fly check box.
    2. In the Display Options area, select the 3D MinMax check box.

    The position and value of the maximum and minimum values is displayed.

  8. Define a radius limit and reduce the number of colors in the color scale:

    1. In the Type area, select Limited.

      The Surfacic Curvature Analysis.x dialog box is modified; the color scale is reduced to four colors and three values.



    2. In the Analysis Options area of the Surfacic curvature dialog box, type the value or use the arrows to change the radius value.

    The values in the color scale dialog box are updated automatically.

    Minimum curvature and radius values are displayed.



  9. In the Type area, select Inflection Area.

    The Surfacic Curvature Analysis.x dialog box is modified; the color scale is reduced to three colors and no values.



    This analysis enables you to identify the curvature orientation:


    • In green: the areas where the minimum and maximum curvatures have opposite orientations.
    • In blue: the areas where the minimum and maximum curvatures have the same orientation.


    Note: Inflection lines created during Inflection Lines analysis are always created within the green area.

  10. When you have finished working with this command, do one of the following:


    • To create the analysis, click OK.

      The analysis is added to the specification tree where it is identified as Command_Name.Analysis.x.

      The analysis will be updated automatically whenever you modify any of the elements in the analysis (for example when you deform an element using control points).

    • To abandon the analysis, click Cancel.