What’s New in AliasStudio  > Modeling > 
Line Perpendicular
 
 
 

The Line perpendicular tool in the Keypoint curve toolbox (Line Tangent & Perp > Line perpendicular) now lets you create lines perpendicular both from and to surface curves (curves on surface, surface edges, isoparms) in addition to free curves.

The surface curves are treated like normal curves, so that the line is perpendicular to the surface curve, but not normal to the surface. A line perpendicular to a 3D curve at a given point can lie anywhere in a plane normal to the curve’s tangent at that point. The specific direction of the line is determined by the second point selected, as well as the choice of the True or Projected option.

These options are initially set in the option box, and determine the initial values of the buttons that appear at the bottom of the window after choosing the tool. This way, it is possible to create different versions of the tool that can be placed on a shelf.

Degree

The degree of the Line Perpendicular. Values range from 1 (default) to 7.

True

The line is perpendicular to the curve in 3D space (as seen in the Perspective window) although it may not appear perpendicular in all orthographic views.

Projected

The line appears perpendicular to the given curve in the active orthographic view. For a Perspective window, turn off Perspective in the Viewing Panel to get an orthographic view.

From Curve

The line extends from the selected point on the curve, perpendicular to the curve, and ends as close to the second point as possible. If the second point is selected on a curve, the line will end on that curve.

To Curve

The line extends from the selected point to the selected curve and is perpendicular to the curve.

Setting up the options

You may want to create different instances of the tool on the shelf for each type of Line Perpendicular you plan to create.

  1. Choose Line Tangent & Perp > Line perpendicular ❐ in the Keypoint curve toolbox.
  2. Set Type to either True or Projected.
  3. Set Select to From Curve to create a line perpendicular from a curve, or To Curve to create a line perpendicular to a curve.
  4. Click Save or Go.

Creating a line perpendicular “From” a curve

  1. Choose Line Tangent & Perp > Line perpendicular in the Keypoint curve toolbox, or the appropriate version of the tool from the shelf.

    A set of 6 buttons appear in the active window: True|Projected, From Curve|To Curve, Next|Change Settings. The button settings from the option box show as active.

  2. If you need to change the settings, click Change Settings, then:
  3. Select the curve from which you want to make the line perpendicular.
  4. Select a point in space, or a curve.

    A keypoint line is created that extends from the point selected on the first curve (to which it is perpendicular) to the location closest to the point selected. If the second item selected was a curve, the line meets the curve at the point closest to where you clicked.

  5. You can modify the position of the start point while in the tool and see the line update interactively. If the second item selected was a point, you can move the end point of the line to adjust its length.You can also type in the line length.
  6. Click Next to create another line perpendicular with the same options. Or click Change Settings to choose different options.

Creating a line perpendicular “To” a curve

  1. Choose Line Tangent & Perp > Line perpendicular in the Keypoint curve toolbox, or the appropriate version of the tool from the shelf.

    A set of 6 buttons appear in the active window: True|Projected, From Curve|To Curve, Next|Change Settings.The button settings from the option box show as active.

  2. If you need to change the settings, click Change Settings, then:
  3. Select a point that will be the end of the perpendicular line. To select a point on geometry, hold the Ctrl or Ctrl + Alt keys to snap to it.
  4. Select a curve that the line will be perpendicular to.

    A keypoint line is created that extends from the selected point to the selected curve and is perpendicular to the curve.

    If no perpendicular line can be found on the curve to the specified point, linear extensions are built at the start or end of the curve, and the perpendicular is built from those.

  5. You can modify the position of the end point while in the tool, and see the line update interactively.
  6. Click Next to create another line perpendicular with the same options. Or click Change Settings to choose different options.