Using Control Points Diffusion Laws

When using the Control Points capability, you need to define diffusion law options. See also Using Control Points Cross Diffusion Laws.
A diffusion law defines the type of deformation that is to be applied to the selected control points and mesh lines which are directly manipulated:
  • Diffusion laws:
    • Constant Law: deforms all the selected control points identically.
      Using this law, you can translate all selected points at a time, even if they belong to several surfaces or curves, provided the active support options Normal to compass and Compass Plane.
    • Linear Law: deforms all the selected control points with a linear law.
    • Concave Law: deforms all the selected control points positioned on a linear concave.
      This option is P2-only.
    • Convex Law: deforms all the selected control points positioned on a linear convex.
      This option is P2-only.
    • Bell Law: deforms all the selected control points with a bell law.
      This option is P2-only.
  • To link/unlink the diffusion laws with the cross diffusion laws:
    • Link Laws: diffusion laws with the cross diffusion laws are linked, the selected cross diffusion law selects automatically the equivalent diffusion law.
    • Unlink Laws: diffusion laws with the cross diffusion laws are unlinked.
Open the FreeStyle_Part_38.CATPart document.

  1. Click the Control Points icon:
    The Control Points dialog box appears.

  2. Move the Compass onto Surface.3.

  3. Click the Normal to compass icon if not already selected:

  4. Click the Mesh only icon from the Options frame:

  5. Click the Cross Constant Law icon if not already selected:

Constant Law

Follow steps 1 to 5 and then work on the steps mentioned below.

  1. Click the Constant Law icon:

  2. Select the mesh line.

  3. Drag the control point to the corner of the surface, close to the cursor has shown in the image below.

    The deformation applied to one point is applied to all other selected points.
    In the image below, the manipulator is displayed in a corner of the surface, but all points lying on the selected mesh lines undergo the same translation.

  4. Click OK to validate the modifications and close the dialog box.

Linear Law

Follow steps 1 to 5 and then work on the steps mentioned below.

  1. Click the Linear Law icon:

  2. Select the mesh line.

  3. Drag the control point to the corner of the surface, close to the cursor has shown in the image below.

    The deformation progresses along a straight line between the most distant selected points.

  4. Click OK to validate the modifications and close the dialog box.

Concave Law

Follow steps 1 to 5 and then work on the steps mentioned below.

  1. Click the Concave Law icon from the Diffusion frame:

  2. Select the mesh line.

  3. Drag the control point to the corner of the surface, close to the cursor has shown in the image below.

    The deformation progresses along a concave curve between the most distant selected points.

  4. Click OK to validate the modifications and close the dialog box.

Convex Law

Follow steps 1 to 5 and then work on the steps mentioned below.

  1. Click the Convex Law icon from the Diffusion frame:

  2. Select the mesh line.

  3. Drag the control point to the corner of the surface, close to the cursor has shown in the image below.

    The deformation progresses along a convex curve between the most distant selected points.

  4. Click OK to validate the modifications and close the dialog box.

Bell Law

Follow steps 1 to 5 and then work on the steps mentioned below.

  1. Click the Bell Law icon from the Diffusion frame:

  2. Select the mesh line.

  3. Drag the control point to the corner of the surface, close to the cursor has shown in the image below.

    The deformation progresses along a concave curve up to the mid-point of the most distant selected points then switches to a convex law.

  4. Click OK to validate the modifications and close the dialog box.