ExtractControlPolygon

Creates a polyline through the control points
of a curve, or a polygon mesh through the control points of a surface.

Steps:

  • Select

    curves or surfaces.

  • This creates polylines and/or meshes that have vertices at the original objects’ control points.

Notes

  • The ExtractControlPolygon command is useful if you want to extract control polygons as objects.

  • It is possible to use the ExtractControlPolygon command to create polygon data that you can export and manipulate in a program that handles mesh smoothing.

Rhinoceros extractcontrolpolygon Extract curves/surfaces

Mesh > Extract Mesh from NURBS Control Polygon

Rhinoceros Menu2 Extract curves/surfaces

Mesh > From NURBS Control Polygon

Rhinoceros Gray Book Open Extract curves/surfaces Related topics…

ExtractIsocurve

Creates curves that duplicate surface isoparametric curves at specified locations on the surface.

Steps:

  1. Select

    a surface.

  2. The cursor

    is constrained to the surface, and isoparametric curve
    display at cursor.

    The draft angle
    of the surface displays at the status bar.

  3. Pick

    to create the curve(s).

  4. Note: Use the Int object snap for snapping to isoparametric curve
    intersections.

Options

Direction

Specify the u-direction
, the v-direction
, or both.

Toggle

Toggles the direction between u and v
.

Notes

  • The ExtractIsocurve command creates the simplest possible curve exactly on the surface in u, v or both directions
    .

  • The ExtractIsocurve command is useful for creating trimming curves on surfaces. You can make surfaces trimmed along isoparametric curves into untrimmed surfaces with ShrinkTrimmedSrf
    .

  • You can use isoparametric curves to recreate an existing surface with different parameterization. To do this, extract several isoparametric curves, and Loft
    a surface through them.

  • If you need to put angled cross sections along a surface, use the Section
    command instead of the ExtractIsocurve command. If you need curved cross sections, use the Project
    or Intersect
    commands.

  • The Knot
    object snap can be used to create isoparametric curves at exact knot
    locations.

  • In contrast to the InsertKnot
    command, the ExtractIsocurve command creates separate curves that are not attached to the surface.

  • If you need to place an object on a surface, use the ExtractIsocurve command to add visual cues or locations that can be snapped to on the surface area and help position the object. Using the ExtractIsocurve command does not change the surface in any way.

Rhinoceros extractisocurve Extract curves/surfaces

Curve From Object > Extract Isocurve

Rhinoceros Menu2 Extract curves/surfaces

Curve > Curve From Objects > Extract Isocurve

Rhinoceros Gray Book Open Extract curves/surfaces Related topics…

ExtractPt

Places point objects at curve control point
or edit point
locations, surface control point locations, and polygon mesh vertices.

Steps:

  • Select

    curves, surfaces, or polygon mesh objects.

  • Rhino creates point objects for every control point in the object.

To extract selected points only

  1. Turn on the control points
    or the edit points
    on an object.

  2. Select

    the control or edit points to duplicate.

Rhinoceros extractpt Extract curves/surfaces

Point > Extract points

Curve From Object > Extract Points

Rhinoceros Menu2 Extract curves/surfaces

Curve > Curve From Objects > Extract Points

Rhinoceros Gray Book Open Extract curves/surfaces Related topics…

ExtractSrf

Separates or copies a surface or a copy of a surface from a polysurface.

Steps:

  • Select

    the surfaces.

  • The surfaces are separated from the polysurfaces. The remainder of each polysurface will stay joined.

    The extracted surface is also removed from any groups to which the original surface may belong.

Notes

  • When you are extracting a surface from the polysurface the ExtractSrf command can save you a lot of time (as opposed to Explode
    ). This is because it lets you extract only the selected surfaces from the polysurface, and so there is not as much joining work to do afterwards.

Options

Copy

Rhinoceros extractsrf Extract curves/surfaces

Solid Tools > Extract Surface

Geometry Fix > Extract Surfaces (Right click)

Main2 > Extract Surfaces (Right click)

Popup > Extract Surfaces (Right click)

Rhinoceros Menu2 Extract curves/surfaces

Solid > Extract Surface

Rhinoceros Gray Book Open Extract curves/surfaces Related topics…

ExtractSubCrv

Separates or copies curve segments from a parent polycurve.

Steps:

  1. Select

    a polycurve.

  2. Select curve segments.

Options

Copy

Rhinoceros extractsubcrv Extract curves/surfaces

Curve Tools > Extract Sub-curve

Rhinoceros Menu2 Extract curves/surfaces

Curve > Curve From Objects > Extract Curve

Rhinoceros Gray Book Open Extract curves/surfaces Related topics…

DeleteSubCrv

Removes a portion of a curve that is between two selected locations.

Steps:

  1. Select

    a curve.

  2. Pick
    a start for the deletion.

  3. Pick an end for the deletion or enter a length.

Rhinoceros DeletesubCrv Extract curves/surfaces

Curve Tools > Delete Sub-curve

Rhinoceros Menu2 Extract curves/surfaces

Curve > Curve Edit Tools > Delete Subcurve

Rhinoceros Gray Book Open Extract curves/surfaces Related topics…

ExtractWireframe

Creates curves that duplicate surface or polysurface isoparametric curves displayed in the wireframe
view.

Steps:

  • Select

    surfaces or polysurfaces.

Rhinoceros extractwireframe Extract curves/surfaces

Curve From Object > Extract Wireframe

Rhinoceros Menu2 Extract curves/surfaces

Curve > Curve From Objects > Extract Wireframe

Rhinoceros Gray Book Open Extract curves/surfaces Related topics…

CreateUVCrv

Creates curves that duplicate the untrimmed boundary and trim curves of a surface as planar curves onto the world x-y plane.

Steps:

  • Select

    a surface.

Note: The control polygon determines the sizes of the uv curves.

Rhinoceros createuvcrv Extract curves/surfaces

Curve From Object > Create UV Curves

Rhinoceros Menu2 Extract curves/surfaces

Curve > Curve From Objects > Create UV Curves

Rhinoceros Gray Book Open Extract curves/surfaces Related topics…

 

Extract curves/surfaces