Generate Patches

images/download/attachments/113546693/CmdCADGeneratePatches.svg

This command allows you to generate CAD surfaces from a mesh and a polyline network. The surface is made of patches fitted onto the mesh.

Before launching the command, you must select the mesh and a polyline network previously designed (polylines and/or set of polylines).

A network of polyline can be obtained through different workflow:

automatically with the command Create Network
manually using all the commands creating sections on a mesh. For example, Freehand sections, Single Breaking Line or Projected Polyline

images/download/attachments/113546693/image2019-8-30_15-28-52.png

When you open the command, a pre-computation is launched. A shell composed of CAD curves and faces is computed. All the computed faces will be fitted on the selected mesh.
You can modify the deviation of the computed curves.
To do that, select one curve in the scene, and then, move the slider in order to choose to be closer or smoother.

When you have selected a curve, the deviations are displayed above the slider.

When you move the slider, the command will try to achieve a new max deviation.

If this asked deviation could not be achieved, a warning will be displayed. And you will need to move the slider again to modify the deviation value.
Inside the Results section, you can see:
- The Standard deviation for curves
- The Max deviation for curves, corresponding to the curve having the maximum standard deviation
- The Standard deviation for faces
- The Max deviation for faces, corresponding to the face having the maximum standard deviation
Click Preview to replace the selected curve by the new computed one. The faces will be recomputed, so the shell. Click OK, to validate, or Cancel to exit the command.

Example

Example of generated patchs on a screw mesh with an input set of network polylines:

images/download/attachments/113546693/image2019-8-2_16-55-12.png

Use the functionality to adjust the Input mesh visibility to better visualize the result.

Practise

See the Beginners Guide CAD to see exactly how to construct polylines on the mesh in order to have good delimitations along curvature or sharp edges. This polyline network is very important to have a nice result, otherwise, final surfaces may be not adequate.