Survey Lines

The Line Database Manager (LDM) is used to create survey lines, routes (polylines) and points for use in planning, conducting and processing a survey. These entities can also be imported from various formats. Once created they can be exported to various formats.

Task	Sub-task	Task	Sub-task
Create New File
Add Layers		Create Object	Points Lines Polylines Areas
Generate Winglines	Single Line Polyline	Generate Crosslines	Single Line Polyline
Import Data	Supported Formats ASCII (XYZ) ASCII (Lat/Long) DWG/DXF/PRO KML	Edit Objects	In Data Grid Attributes Points - Data Fusion Lines - Interpolate Polylines - Simplify Polylines - KP Calculations By Mouse Delete Editing Coordinates
Export Data	Autocad DXF Terramodel PRO Google Earth KML	Actions - Clipping	Clip Inside Clip Outside

Create a New Line File

Before any points, lines and/or polylines can be created, a Line Database File must exist.
In the Processing Manager:

Open the File tab.

Click on New.

Click on Line File. This opens an explorer window which defaults to the \LineData sub-folder of the current Project.

Enter a file name. Click on Save.

The new line file is listed in the Project Explorer window.
A SURVEYLINES layer is automatically created. This name may be changed and additional layers generated.
Clicking on the line file name and then the Edit tab opens the Line Tools ribbon.
Press the Edit tab under the Line Tools tab to activate the Line Planning tools:

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Add Layers

To organize points, lines and routes used, perhaps, for different purposes, it is useful to add layers to the single layer created in the new *.qgf file.

Click on to open the Edit Layers dialog.

Click on and then edit the name of the layer added. Add other layers as necessary.

Set colors, pen widths and line style. Primitive Count refers to the number of elements in each layer.

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Create Point, Line, Polyline and Area Objects

Point, line, route and/or area data now needs to be added.

Make sure the focus is on the line database created and on the layer in which the objects are to be added.

Click on the button. The cursor changes to indicate that a point can be selected in the Plan View area:

For a Point, click once with the left mouse button, then click the right mouse button to end the drawing mode.
To create a point with a radius, hold down the CTRL button.

For a Line, click two points with the left mouse button, then click the right mouse button to end the drawing mode.

For a Polyline (route), click multiple points with the left mouse button, then click the right mouse button to end the drawing mode.

For an Area click the vertex points of the area with the left mouse button, then click the right mouse button to end the drawing mode.
Make sure to click on or near the first point to create a closed boundary. In the plan view the figure then fills with a default grey color.
The Shift button can also be used when closing the area boundary. This will automatically invoke the extra options for defining an area.

In each case the Add New Object dialog opens. As depicted in the image below there are slight differences in the dialog. Enter a name, and select the object attributes.

In the case of an area, check the 'Make it an area' tick box to actually create an area. The dialog then changes.

If not activated, the boundary of the area is stored as a polyline and it cannot be filled with a color.

Choose colors for the line and fill.

Use the slider to modify the transparency of the fill color. The plan view responds immediately so you can gauge the effect.

Choose an icon to display in the area.

Choose colors for the line and fill for the icon.

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Generate Wing Lines

Wing lines are simply lines generated parallel to a single baseline or polyline. Creating wing lines requires that a line or polyline be defined first.
Before generating any wing lines, make sure to select the layer on which they must be stored.

Single Line

Start a single survey line

Click on this line in the Plan View. 'Wing lines' (and 'Cross lines') commands become active.
Click on which opens the Wing Lines Settings window:

Enter values and make selections to generate winglines on the port and starboard side of the initial line selection.

Use the Up/Down arrows to increase/decrease the displayed value by 1 (5m for wingline interval).
The naming convention is:

#S: Sequence number
#N: Name of along line
#O: Absolute offtrack
#o: Offtrack

All other text can be added optionally

Press OK to start the creation of the wing lines.

Click on and select Lines to view the results of the wingline generation.

Click on to store generated lines.

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Polyline/Route

For a polyline, click on the line in the Plan View.

The 'Wing lines' (and 'Cross lines') commands become active.

Click on which opens the Wing Lines Settings window.

Enter values and make selections to generate winglines on the port and starboard side of the initial line selection.

This image shows the settings and result when generating wing lines for the entire polyline/route:

This image shows the settings and result when generating wing lines for the a portion of the polyline/route:

Click on to store generated lines.

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Generate Cross Lines

Cross lines are simply lines generated at an angle to a single baseline or polyline. Creating cross lines requires that a line or polyline be defined first. 

Before generating any cross lines, make sure to select the layer on which they must be stored.

Single Line

Click on the single survey line in the plan view.

The 'Cross lines' (and 'Wing lines') commands become active.

Click on  which opens the Cross Lines Settings window:

Enter values and make selections to generate cross lines at intervals along the initial line selection.

The naming convention for the cross lines:

#S: Sequence number
#N: Name of along line
#K: Station number (KP)
#M: Station number (MP)
#U: Station and offset (USA)

 All other text can be added optionally.

Entering an angle rotates cross line bearings so they are no longer perpendicular.
This image shows the settings and result when generating wing lines for the entire polyline/route:

Press OK to start the creation of the cross lines.

Click on and select Lines to view the results of the cross line generation.

Click on to store generated lines.

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Polyline/Route

Click on the polyline/route in the plan view.

The 'Cross lines' (and 'Wing lines') commands become active.

Click on  which opens the Cross Lines Settings window.

Enter values and make selections to generate cross lines at intervals along the initial line selection.

Click on to store generated lines.

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Import Data to New Line Database

Click on Line file to which data is to be imported

Double click on the Line Tools ribbon tab to activate the Line Tools

Click on Import to initiate the Import Wizard

Supported File Formats

On the first page of the wizard, select the data file format type. The contents of remaining wizard pages depends on the data format chosen.
The following formats are supported:

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Import ASCII (X/Y/Z) Wizard

Select ASCII Files

Add the ASCII file(s) to be imported

Click Next

Two predefined layouts are available: E N H (Comma delimited) and E N H (Tab delimited). If data in the ASCII file has a different layout, there is an option to create a new user defined import layout; select 'New Format' from the drop down list or click on  . This opens the Layout Editor:

Click the 'New' button.

Provide a name for the new layout and the delimiter used.

In case the ASCII file contains header information, define the row on which the coordinates start.

Click on the 'Add' button in order to define the fields of data in the ASCII file being imported.

Select the first field type. Repeat until all fields are defined. 

To test decoding of the ASCII data, copy and paste a line from the file into the 'Example' space provided.

Click 'Test' and check decoded sentence.

Clicking OK returns you to page 2 of the import wizard where you select the 'Primitive Type', enter a 'Layer Name' and check/change the 'Skip Rows' number.

Click 'Finish' and the imported points/lines/polylines are shown as a layer in the plan view.

Additional ASCII files may be added to this line file if necessary.

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Import ASCII (Lat/Long/Ht) Wizard

This import routine is very similar to importing X/Y/Z ASCII data. The differences are:

Define different fields.

Create a new layout

Give the layout a name, a start row and a delimiter

Add fields and setting scale factors and/or formats

Copy and paste a line from the ASCII file

Test decoding.

Geographical to grid conversion

Geographical coordinates are converted to grid during the import so you must make sure to have the correct template database active.

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Import DWG, DXF or PRO Wizard

As with an ASCII import:

Select DWG, DXF or Terramodel Files as File Format

Browse to select the DWG, DXF or PRO file to be imported

On the second page of the wizard:

Use a combination of check boxes, Select All, and Invert Selection to choose which layers of the DWG/DXF/PRO to import

Check the Skip Empty Layers box if there is a need to avoid importing empty layers

Click Finish

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Import KML Wizard

A line file may also be defined in a KML file. Import is similar to other file formats described above.

Select KML as File Format

Browse to select the KML file to be imported

On the second page of the wizard....... 

After import the lines should appear in the plan view. You may have to click on a different element and then click back on the line file.

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Edit Points, Lines, Polylines and Areas

In Data Grids

Click on and choose which entity to edit.

Coordinates and attributes are shown in a data grid like this:

In the Processing Manager, data grids are often used for showing properties of multiple items located in such places as the Points, Lines, Polylines and Areas Editor and the PM Project Explorer.

The data grids offer many opportunities for customization such as filtering, sorting and grouping.
Most of these options are found by right clicking on the column headers to open the contextual menu.

All functions are fairly self explanatory except, perhaps, for the following:

Points, Lines, Polylines and Areas - Attributes 1 and 2

Custom numeric attributes. Change the attribute names by right clicking on the column header selecting Set attribute names.

Attribute 1 options -

• • T.M.D. (True Measured Depth, used in VSP surveys)

  • Velocity

  • SD (horizontal)

  • Weight (horizontal)

Attribute 2 options -

• • T.V.D. (True Vertical Depth, used in VSP surveys)

  • Velocity

  • SD (height)

  • Weight (height)

For example a Weights column can be created or a column with Standard Deviation values.
The custom attributes can be used in the Data Fusion to calculate a weighted mean or least squares approach.

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Points - Data Fusion

Use this option to calculate the mean of the points selected in the Points data grid list.
The calculation options are:

• • Mean - Calculates the new position based on the average positions of the selected points.

  • Weighted mean - Calculates the weighted mean of the selected points. Points with zero weight are excluded.
    The weights can be entered in the attribute columns in the Points Editor.

  • Least square approach - Calculates the new position using a least squares approach.
    All selected points must have proper Sd values, which can be entered in the attribute columns in the Points Editor.

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Lines - Interpolate

Use this option to create interpolated lines between the two or more lines selected from the list in the Edit Lines window.

For example, two lines are defined:

Before adding interpolated lines make sure the correct layer is selected:

In the Edit Lines data grid select both lines.

Click on the Interpolate button which opens the Interpolation Settings window.

Press OK to start the interpolation.
The new lines are displayed in the Plan View when OK is pressed in the Edit Lines dialog.

Interpolation is also possible between 3 or more lines:

Click on to store interpolated lines.

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Polylines - Simplify Polyline

The line simplification is used to reduce the number of segments in a polyline without losing too many details.

Polylines - KP Calculations

This function either extrapolates KP values between the selected control points or it calculates values between entered KP values.

In this example:

...the following settings were used to compute KP values:

Examples:

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By Mouse

Delete

Points, lines, polylines and areas may be deleted by clicking on the entity in the Plan View panel.

Line color turns grey.
Click on Remove in the Actions command group.

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Editing Coordinates

For lines, polylines and areas, clicking once on the line changes the color to grey.
Clicking again changes the line color back and adds edit points at each vertex.
Hover over one of the edit points, click and drag.

Clicking once on the route changes the color to grey.
Clicking again changes the route color back and adds edit points at each vertex.
Hover over one of the vertices, click and drag.
Release mouse button when vertex is appropriately placed.
While the focus is still on the route line edit points remain at each vertex for further moving.
Click anywhere in the panel and the route reverts to grey.
Removing the focus from the route changes the line color back to its original.

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Export Data

Export data to one or more of the following formats:

Actions - Clipping Lines

By way of an example, a survey to be performed in an area with an irregular coastline and an island:

Clip Outside

Make sure the correct layer is selected, i.e. the layer on which the lines to be cut are resident.

Select the larger polygon and click on .

For the lines that cut the polygon, the pieces of lines that fall outside are cut.
Any lines that do not cut the polygon are unaffected and should be removed by hand.

Clip Inside

Select the smaller polygon and click on .

Before clipping:

After clipping:

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