Surfaces > Boundary Surfaces > Multi Blend

Creates a surface from three or more input edges.

MultiBlend Control options

Edge Split Type

Defines the seam positions of the multi blend surfaces on the selected edges, if no single surface is created.

User Defined – Locate the seam positions individually by dragging the edge point handles.

Flexure – The seam position is calculated from the arc length and the curvature of the edge.

Arc Length –The seam position is set to the middle of the side with respect to arc length.

Parameter – The seam position is set to the middle of the side with respect to the original parameter flow.

Edge Continuity

Defines the global quality of the transition across the selected surface edges and curves: G0 Position, G1 Tangent, or G2 Curvature.

If adjacent edges or curves are not connected to an edge with tangent continuity, the corresponding side will initially be set only to position continuity.

Seam Continuity

Define the continuity at the seams: G1 Tangent, or G2 Curvature.

Shape Factor

Controls the shape of the multi blend surface by means of a shape factor. If the Shape Factor option is not available, a value of 1.0 is used.

Cross Variation

Controls the calculation of transitions across the selected edges. It is only relevant for tangent or curvature continuous transitions. Use this option for better control point distribution within the created surfaces. It requires a higher degree for the calculation of a result with the best possible accuracy.

Inner Curvature

Star Point Modification

The star points are calculated automatically with the first calculation of the blend surfaces. After this calculation, you can change the points as follows:

Automatic – The star points are calculated automatically.

Planar – Move the star point on the blend surface by dragging the circle manipulator. The surface normal at the star point is preserved.

Normal – Move the star point normal to the blend surface by dragging the arrow manipulator. The surface normal at the star point is preserved.

View – Move the start point in the view by dragging the arrow manipulator.

U, V Degree

Allows you to specify a uniform degree for the creation of multiple surfaces or two different degrees for the creation of a single surface. If this option is inactive, the degree is determined internally depending on the input geometry and the algorithmic requirements. The created surfaces will always be single-span surfaces.

Single Surface

The multi blend can be created as a single surface. In case of a three-sided hole, a triangular surface is created, which due to system requirements must be subdivided into three rectangular surfaces. In the case of a four-sided hole, a rectangular surface is created. Only in this case is it possible to specify two different degrees.

Control options

Auto Update

Update the new surface automatically as you change the values in the MultiBlend Control window.

Check Deviation

A deviation measurement showing the maximum deviation between the surfaces.

Chain Select

Selecting a boundary input curve also selects all other boundary curves that are tangent continuous with it.

Create History

Save the history of the new surface for later editing. If you select Create History, you can modify the curves that were used to create the surface, and the surface will update.