This task explains how to further smooth the surface onto the cloud of points following the distance and reflect line analyses.

1. Choose the Tools > Options menu item, Shape > FreeStyle tab, set the attenuation value to 0.01 and click OK.

2. Select  the roof surface and click the Control Points icon:

   The Control Points dialog box appears:

3. Click the Local Normals icon:

4. Click the Constant Law icon:

5. Right-click the Symmetry Plane selection field and select the ZX Plane from the contextual menu.

6. Double-click the Symmetry icon to lock the functionality.

7. From the Dashboard, click the U, V Orders icon:

8. Set the order numbers to Nu=5 and Nv=7 using the contextual menu, to increase the number of mesh lines in U and V respectively.

   This brings more flexibility in terms of modifications.

9. Decrease the deformation step to 0.75mm in the Dashboard toolbar.

10. Right-click the mesh and select the Freeze command from the contextual menu, to avoid selecting points from the cloud.

11. Select the central U mesh line and move it till you display green points instead of red points.

    You may also need to decrease the step and attenuation values and the number in U and V to reach a smoothed surface, i.e. displaying mostly green points, that is lying between -0.15mm and 0.15 mm from the cloud of points.