Drawing Objects
Drawing commands are found in the Drawing Toolbar.
The geometry produced by these commands can include points, lines, or curves.
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Points
Point objects are the simplest entities, marking a single point in 3D space. They can be positioned anywhere in space and are most often used as as placeholders.
Point: Draw a single point object at a specified location.
Points: Draw multiple point objects.
Point Cloud: Create a set of vertices from point objects.
Lines and polylines
A line is formed by a succession of points that create a continuous stroke. Line objects are degree 1 curves with no bends.
A polyline is a series of line or arc segments joined together; it can be open or closed.
Polyline: Draw a series of joined line segments.
Rectangle: Draw a rectangular closed polyline with options for starting.
Polygon: Draw a closed polyline with a specified number of sides.
Curves
Free-form curves
Free-form curves in RhinoLands are NURBS curves. A NURBS curve is defined by its order, a set of weighted control points, and a knot vector.
RhinoLands offers a variety of methods for creating free-form curves.
Curve: Draw a curve from control point locations.
InterpCrv : Fit a curve through picked locations.
Sketch : Drag the mouse to draw a curve.
See: Wikipedia: Non-uniform rational B-spline (NURBS).
Conic-section curves
Conic section curves are formed by the different intersections between a cone and a plane, as long as the plane does not pass through the vertex.
RhinoLands commands allow drawing specific conics, which are degree 2 curves. An arc is a segment of a circle.
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Conic-section curve examples (left) Circle, (right) Ellipse.