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Line Geometry

Use this dialog to create or edit the geometry of: * Line/polygon in a standard application layer * Line (polygon) in a surveying application layer * Line in an SFI model

Where can I find the dialog?

In the Planning, Design, and Execution toolbox, select Create Line in Application Layer... or Horizontal Curvature (Line Definition).

Using the dialog

You can edit the geometry in two ways: * Via the properties dialog * By using "grips"

When editing via the properties dialog, the different elements of the line have the following colors:

  • Straight line: Orange
  • Clothoid: Light green
  • Radius: Dark green

During editing, you can enable or disable helper options for dynamic lines, such as dynamic text and helper geometry.

The icon for helper options is found on the toolbar below the map window.

Tip

When using the SFI model for road design, you typically select a road class. Editing functions and additional features related to this are described in more detail in the general help.

Editing via the object's properties dialog

You can add points and roundings dynamically on the screen or manually in the properties dialog. The most common method is dynamic construction. Manual entry can be used, for example, if you have a line definition on paper that you want to digitize.

Dynamic editing

When creating new lines in Gemini Terrain, the angle point method is used. This means you place all angle points before adding roundings at those points.

Angle points are placed before radii are added at these bends

Procedure

  1. Select the function to create horizontal curvature in the SFI model or line/polygon in an application layer.
  2. Point and left-click in the map to register angle points.
  3. Deactivate the Insert Point icon on the right mouse button.
  4. Point and left-click on the first angle point (the point and the line to the next point will be highlighted in blue).
  5. Select the Insert/Edit Rounding icon on the right mouse button and enter the desired rounding with or without clothoids.
  6. Select the next angle point and add a new rounding. Continue until all bends have the desired rounding.

Note

For lines in the SFI model, there will be a link to the requirements in the road standard if a design class is selected. The program will automatically suggest the minimum rounding as you add angle points.

You can also follow existing lines in application layers or models, both in plan and 3D. Activate Follow Line in the context menu. When you snap to a point on the line—endpoint, midpoint, or intersection—the line you are following will be highlighted in green on the screen.

Example of using Follow Line**

Warning

You can only follow continuous line elements. If, for example, you have two line objects with common start and end points that you want to follow, you cannot follow across these. Possible solution: Follow the line to the endpoint, register it, turn Follow Line off and on again, and continue on the next line object. Alternatively, you can merge the line objects first, for example, using topology cleanup.

Edit existing line (polygon)

Open the properties dialog for an existing object by double-clicking it in the map or list, or select Properties... from the context menu.

Insert point arbitrarily on the line

Select the point before which you want to insert new points, and activate the Insert Point icon on the right mouse button. All inserted points will be placed immediately before the selected point. Therefore, start with the one furthest away. You can also use Follow Line here.

The line element after the selected point will also be highlighted in blue. This also indirectly shows the direction of the line.

An angle point is selected, and the following line element is highlighted in blue

Continue the line from the last point

If you want to continue a line from the last point, click next to the endpoint. Then right-click and select Insert Point. If you click on the endpoint, it will be marked with a cross and the point will be inserted before it. You can also check this via the properties dialog. If you click next to the last point so that it is not highlighted in blue, the empty line below the last point in the list will be highlighted.

Move a line with arcs and clothoids dynamically

To move a line with arcs and clothoids dynamically, you can use the functions Move Dynamically via Angle Point, Move Dynamically via Point on Line, Move Dynamically Clothoid Endpoint, and Move Dynamically Radius. Select the element you want to edit (radius or clothoid) and choose the function on the right mouse button.

Warning

You must visually check that a solution exists for arcs and clothoids when dynamically moving the line via angle point or point on the line. If you move the line so far that the geometry can no longer be solved, the line will be marked with a thick line and no arcs or clothoids will be drawn.

Tip

All functions on the right mouse button have a shortcut key. You can save many right-clicks by learning these.

Lock direction on line elements

The line editing dialog has a column for information about locked line elements. You can lock the direction of one or more elements in the list. Only the direction is locked, not the length of the line element. Dynamic editing can therefore make the line element longer or shorter.

Figure caption: A = Locked direction

Manual editing

This is done using the functions on the right mouse button in the dialog. Here you will also find several useful calculation functions.

Procedure

  1. Select the function to create a line or polygon.
  2. Right-click and select the Dialog On/Off icon.
  3. Right-click in the list and select Insert....
  4. Enter start point, curve point, and end point.
  5. Then select the start curve point, right-click, and select Edit....
  6. Select Arc 2 Points and enter the radius (remember the sign).

Figure caption: A = Curve point, B = Angle point

The functions on the right mouse button in the dialog are described in more detail in a separate section.

Editing via "grips" (using handles)

"Grips" are especially useful when you want to edit the geometry of existing lines. Note that you do not have an undo option in the same way as when editing via the properties dialog. When using the properties dialog, you can always click Cancel. Once you have moved the point with grips, you do not have this option.

Note

For all editing, you can reload the last save. The Ignore Changes... option is available in both the properties dialog for application layers and the properties dialog for SFI models.

The toolbar contains the icon to enable or disable "grips editing"

By pointing and clicking on a line or polygon when "grips" is active, some points are highlighted with a symbol. You can grab and move these handles directly.

When you point to a handle, a tooltip appears explaining what happens when you left-click the point. Other relevant options appear when you right-click.

Tooltip for left mouse button when hovering over a handle

If the line contains arcs and clothoids, extra handles appear. By dragging these, you can dynamically change the line.

The figure shows "grips" for a line with arcs

Information in the element column

For lines, the column shows the length L=. The length is also displayed in the field above the coordinate list.

If the line has a gap, Invisible will also appear in the column. Invisible will be marked at the last point before the gap begins. For lines with gaps, the column will show the length of both line segments.

For polygons, the column also shows area A=. If the polygon has an island, the column will show Invisible in the same way as for lines. The column also shows the areas for both the main polygon (+ area) and the island polygon (- area). The sum of these polygons can be found under the properties tab.

3D Line

In a 3D line, all points have elevation. You can enable or disable the 3D line option. Note that all elevations are deleted if you change a 3D line to a 2D line.

Some comments on 3D lines:

  1. 3D lines have a separate option in the context menu to extrapolate the line in 3D.
  2. They are drawn with exact elevations in 3D view. Line definitions with undefined elevation are draped on the terrain.
  3. The line definition command LineDef(*.sfi) is automatically inserted into the longitudinal profile when you generate or view existing profiles.

Using helper lines

In some cases, it may be necessary to construct helper lines. Once the helper lines are constructed, you can snap to them. Helper lines are described in more detail in the general help.

In many cases, you may want to create a line that is only a circle. For this special case, you can use helper geometry.

Procedure

  1. Create a helper circle.
  2. Select Create Line in Application Layer....
  3. Hold down the [Ctrl] key.
  4. Point to the helper circle and left-click (provided you have not already registered any points in the line).
  5. Answer Yes to create a full circle.

The Break column

The break column shows the angle difference between two consecutive elements. If you have not added roundings, you will get a break at each bend. It may also be that elements in the line have been moved without the corresponding curve point being updated. The break column thus provides a check that the line is a mathematically correct centerline for the road.

Figure caption: B = Break angle

The Point ID column in surveying application layers

Line objects in surveying application layers are linked to point objects. In this way, you can ensure that the coordinates of the line points are updated when changes are made, i.e., after calculation of the measured points.

This link is shown in the Point ID column.