Snapping

For options that require graphical data input, the Snap options allow you to quickly and easily "snap" exactly to any point or line segment.

Snap Options on the View menu are applicable only to the two-dimensional views (i.e., Opening Section View or Support Designer Views). It can be useful for defining the Opening Section, defining the Ground/Truncation Surface, and with options such as Move Vertices and adding or editing support.

If you select the Snap Options sub-menu on the View menu, you will see the following options in the Snap dialog:

• Snap
• Ortho Snap (Ortho)
• Object Snap (OSnap)

These options can be enabled by selecting the appropriate checkbox in the Snap menu. They can also be toggled on or off by using the indicated function keys. The Snap Options in UnWedge operate as described below.

Snap

If the Snap option is selected, this allows the user to snap exactly to:

1. Any vertex of any model entity ( Vertex Snap). If you hover the mouse over any vertex, the cursor will change to a circle, indicating that you may snap exactly to the vertex location.
2. Any line segment of any model entity ( Line Snap). When the cursor is hovered over any line segment in the view, the cursor will change to an X. If you click the mouse when the X is displayed, the point will be snapped exactly to the line segment.
3. Any grid point (if the grid is displayed) ( Grid Snap). If the Grid is displayed, you can snap exactly to grid points when the mouse is hovered over a grid point. The cursor will change to a small circle when placed over a grid point, to indicate that you may snap to the grid point.
4. Any extension line displayed by the OSnap option (see below for details).

Ortho Snap (Ortho)

The Ortho Snap option allows the user to snap exactly to the horizontal or vertical directions.

If the line you are currently drawing is nearly horizontal or nearly vertical, a small "right-angle" (i.e., "orthogonal") symbol will be displayed beside the cursor, and the line will snap exactly to the horizontal or vertical direction. This indicates that you can snap the line exactly along a horizontal or vertical direction.

TIP: The Ortho Snap option can be useful in conjunction with Line Snap (see above), since it allows you to simultaneously draw an exactly horizontal or vertical line, and also snap the point exactly to a line segment.

Object Snap (OSnap)

The Object Snap option (OSnap) allows the user to create temporary extension lines which are aligned with vertices or line segments. If the Snap option is also enabled, these extension lines can be snapped to, in the same manner as described above for the Line Snap.

To use Object Snap:

1. Select OSnap from the Snap dialog, the right-click menu, or use the F3 function key.
2. While in this mode:
• If you place the cursor over any vertex of any modelling entity, red dotted "extension lines" will be automatically drawn from the vertex, in the horizontal and vertical directions.
• If you place the cursor over any line segment of any modelling entity, a red dotted extension line will automatically be drawn, extending from the line segment, in both directions.
3. While these red dotted lines are displayed on the screen, you may snap exactly to these extension lines, if the Snap option is also enabled, as described above for the Line Snap. These extension lines can be useful as guides while creating or editing your model. Note that these lines disappear when the current action is completed, they do not remain on the model.

Toggling the Snap Options

There are numerous ways of toggling the Snap options:

• Select the Snap option in the View menu, to display the Snap dialog
• While adding or editing the Opening Section, a right-click will bring up a context menu with the Snap options.
• The F9 function key will toggle the Snap option.
• The F8 function key will toggle the Ortho Snap option.
• The F3 function key will toggle the Object Snap option.