Projecting Curves

task target This task shows how to project curves on clouds of points or meshes.

The action proposes options to:

  • project the curves perpendicularly onto a mesh (not available for clouds of points),
  • modify the projection direction, 
  • smooth computed scans directly into curves. 
aprereq.gif (1231 bytes) 


Open the CurvesOnCloud1.CATPart model the from the samples directory.
You can use either the cloud or the mesh.
  1. Click Curve Projection  I_CloudProjCrv.gif (1718 bytes). The curve projection dialog box is displayed.

  2. Select the curves to project and the target cloud or mesh.  

    Curves can be selected:
    • from the specification tree,
    • with a selection trap,
    • with the preselection navigator.

  3. If the target is a cloud of points, the projection is automatically computed along a direction.
    If the target is a mesh, you can select the Projection type from the list:

  4. If the projection is computed along a direction, the direction proposed by default is the Z axis.
    You can choose another direction, using the contextual menu of the Direction field:

    • the Edit Components option let you type the coordinates of the direction:

    • The Compass Direction option takes the compass current orientation as the projection direction.
      If you want to change this direction, modify the compass orientation and re-select Compass Direction
      to take the new direction into account.
  5. If the target is a cloud of points, you may set the working distance:
    the input curve is discretized, and each discretization point is projected on the cloud.
    The working distance is the distance taken into account around each projection point to compute
    the output scan.
    Type 10 then 3:
    The working distance is 10

    The working distance is 3

  6. You can set a sag value:
    the curve to project is discretized according to this sag value, and each discretization point is
    projected on the mesh.
    The Sag is set to 1
    The Sag is set to 0.01

  7. If you want to create curves, select the Curve creation check box.
    The operating mode is the same as for the Curve from Scan action except that only the curvature comb
    (no curvature analysis dialog box) is displayed.

    • If the Curve creation check box is selected, curves and only curves will be created.
    • If the Curve creation check box is not selected, scans and only scans will be created.
    • If you need a complete curvature analysis of the curves you create, you have to create the scans first,
      and then create the curves with the Curve from Scans action.
    • When you modify a parameter, click Apply in the corresponding dialog box to take it into account.
  8. Click Apply to check or update the result. Then click OK to confirm the result and exit the action. 

    • Scans are created in the specification tree under the name Curve Projection.x.
    • Curves are created in the specification tree under the name Curve.x.

end of task