Tool Palettes Evaluate > Surface Evaluate > Horizon > To create curves on surface along the horizon line

Evaluate > Surface Evaluate > Horizon

Produce curves-on-surface from horizon lines as seen from a point in space or from a direction.

See Create curves on surface from evaluation data

Horizon Type

Choose how to project the horizon line onto the surfaces.

Perspective-use the horizon as seen from a certain point in space.

Orthogonal-view the horizon from a certain direction. With this technique, the "sightlines" are parallel and the viewpoint is infinity.

Note that if the horizon does not cross the surfaces when viewed from this point or direction, the Surface evaluate tool will not create any curves on surface.

View Point

The point in space from which to look at the picked surfaces and the horizon.

You can set this with the viewpoint locator when you use the tool.

This option appears when Horizon Type is Perspective.

Point

Enter the name of a point to position/align the Horizon manipulator with it. (You can also click a point to align the manipulator with it. Or you can select the point and the surface before selecting the tool.)

This option appears when Horizon Type is Perspective.

View Direction

The view direction from which to look at the picked surfaces and the horizon.

This option appears when Horizon Type is Orthogonal.

Vector

Enter the name of a vector to position/align the Horizon manipulator with it. (You can also click a vector to align the manipulator with it. Or you can select the vector and the surface before selecting the tool.)

This option appears when Horizon Type is Orthogonal.

> Control Options

Create History

Save the history of the new curves-on-surface for later editing. If you turn Create History on, you can modify the surfaces and the curves-on-surface will update.

Auto Recalc.

Update the curves-on-surface as you change the values in the Horizon window.

> Buttons

Recalc

When Auto Recalc. is off, use this button to update the curves on surface to correspond to the current options.

Undo All

Undo all the changes made by the tool and return to the original surface.

Next

Finish creating curves-on-surface on the current surface and prompt for a new surface to evaluate.

To create curves on surface along the horizon line

Pick the surfaces on which you want to create curves-on-surface.
Choose Surface evaluate > Horizon  from the Evaluate palette menu.

The Horizon control window opens.

Set the Horizon Type.

If the Horizon Type is Perspective, a viewpoint locator appears. Drag this locator to move the viewpoint, or type exact coordinates in the View Point fields in the window.

If the Horizon Type is Orthogonal, type a direction in the View Direction fields in the window.

If Auto Recalc. is off, click Recalc. to create the curves-on-surface.

You can click the Undo All button in the control window to remove the curves on surface, or change the manipulator and click Recalc.

When using the Horizon evaluation type, note that if the horizon does not cross the surfaces when viewed from the point or direction you set, the tool will not create any curves on surface.