From submesh : this check box let user have the ability to select closed lines to define submesh on the selected mesh. If this check box is check, the Create button will be enabled, the Trim button will be disabled because surface from sub mesh will be trimmed in default;

Extract: a method of extracting sub meshes from meshes.

There are two methods to extract sub meshes:

Curve: extract sub meshes by picking curves on the mesh to define closed areas. When this type is selected, the generate button is activated.

Angle: by setting the angle value, pick a mesh face, make the mesh face grow outward under the angle constraint, and extract the sub mesh. When this type is selected, the angle change button is activated.

Increment: sets the incremental value of the angle change.

Create: after you checked the from submesh button, this button will be enabled. Click this button, select some lines to make closed loop, then click right-mouse button, a new surface with the specified tolerance will appear. If you would like to adjust the tolerance of the surface, reset Max Tol and click Apply button, the surface will update.

Symmetric surface: create symmetric surface from the selected points. (disable in the current version)

use symmetric plane: check this button to activate the ' Plan from ' option.(disable in the current version)

Plane from: slection for type of symmetric plane. (disable in the current version)

Shape: topology shape of your mesh model. If your mesh model is like plane, choose plane homeomorphous; if your mesh model is like cylinder, choose cylinder homeomorphous;if your mesh model is like semisphere, choose semi_sphere homeomorphous.

Set control number: this check box let user have the ability to set an initial control point number for the surface. Such as u = 43, v = 23. This check box is only designed for those users who would like to control the surface in advanced way. Sometimes, if user type a reasonable control point number, it will be helpful to increase the speed. Generally, however, user does not need to care this control number, the program will calculate a suitable number automatically.

Degree: surface degree in u-direction and v-direction.

Extending: the extending value which user wants the surface to extend in U-direction and V-direction.

Max Tol: the maximum deviation between surface and mesh.

Smooth: the smooth controller of the surface.

Trim: to trim or untrim the generated surface with the boundary line of the mesh.

Apply: user clicks this button to generate surface. After a surface is generated, if the tolerance is not desired, continue to click this button to get a surface with a desired tolerance.

Error analysis: check this button to analyze the deviation error between mesh and surface.

New: pick a new mesh model to reconstruct a new surface, and the currently obtained surface will be retained.