Digitize

The Map Tools | Layer Tools | Digitize command allows you to write map coordinates to a data file. As you move the pointer across the selected map, the X, Y, and Z map coordinates for the current mouse position are shown in the status bar. Left-click on a map to write digitized points to the Digitized Coordinates dialog.

To use the Digitize command, you must select a horizontal planar map. To ensure that your map is horizontal planar, click on the Map object in the Contents window. Click on the View tab in the Properties window. Change the Tilt (degrees) to 90.

Note: Use the 3D View | Tools | 3D Digitize command to digitize coordinates in the 3D view. Creating 3D digitized coordinate data might be useful for identifying spot locations and writing their XYZ coordinates to a file.

Digitized Coordinates Window

Click the Map Tools | Layer Tools | Digitize command or the button or right-click on a map and select Digitize to enter into digitize mode. Left-click on a map, and the Digitized Coordinates window is displayed.

The digitized X, Y, and Z values are written to the Digitized Coordinates window.

The coordinates for the clicked point are written to the Digitized Coordinates window. Each time the map is clicked, a small, temporary red symbol is drawn on the map, and the map coordinates for the current mouse position are written to the Digitized Coordinates window. In this way, you can digitize boundaries from maps and easily create blanking files from the digitized information. You can also create a blanking file with Map Tools | Layer Tools | Digitize.

The Digitized Coordinates window stays open until it is closed by clicking the button in the top right corner of the Digitized Coordinates window. This allows convenient editing of the data and allows digitizing to start and stop multiple times and be recorded in the same window.

Menu Commands

The Digitized Coordinates window has three menus: File, Edit, and Options.

File

The File menu allows you to save or open a .DAT data file or a Golden Software Blanking .BLN file.

Edit

The Edit menu command allows for common editing, such as undo, redo, cut, copy, paste, delete, find, replace, and select all. These commands work in much the same way as the commands in the Home and Data tabs for a worksheet.

Options

The Options menu allows the user to set the numeric format with the Options | Coordinate Format command. This opens the Label Format dialog, where the numeric format can be set. The period is always used as the decimal separator. No prefix, suffix, or thousands comma can be displayed in the Digitized Coordinates window.

The Options menu also allows the user to specify whether the Z value is included when digitizing a grid based map. Click the Options | Include Z coordinate command. The points you digitize after selecting this command will have a Z value when digitizing a grid based map. When digitizing other maps, such as base maps, or when you are digitizing outside the gridded area, the Z value is not included.

When multiple grid based maps are overlaid, the Z value is determined by the Track map coordinates of option in the Options dialog. When this option is set to Topmost map/layer, the map layer that is above all others in the Contents window is used for the Z value. When the Track map coordinates of option is set to Selected map/layer, the digitized Z value is determined by the current map layer that is selected in the Contents window. If the Track map coordinates of option is set to Selected map/layer and you select a different map layer while digitizing, the Z value will come from the newly selected map layer for new digitized points.

The Options menu also determines if the digitized blanking file assigns the NoData value inside or outside the defined points. By default, the Options | NoData Inside Region option is checked. When saving the digitized coordinates, a 1 is written to the BLN file blanking flag, and the area inside polygons is assigned the NoData value. Click the NoData Inside Region option to change the setting. When NoData Inside Region is unchecked, a 0 is written to the BLN file blanking flag, and the region outside polygons is assigned the NoData value. By default, this setting is remembered during each Surfer session.

Digitizing Information from a Map

To digitize information from a map, follow these steps:

Create a map in the plot window and select the map. You can select an overlay, although the overlay cannot contain a wireframe or surface, or be tilted at an angle other than 90 degrees.
Click the Map Tools | Layer Tools | Digitize command or right-click and select Digitize. The cursor becomes a cross hair to indicate digitize mode.
As you move the cross hair cursor within the plot window, the map coordinates for the position are displayed in the status bar. If the map is a grid based map, like a contour map, the Z values are also displayed in the status bar.

The status bar displays the X, Y, and Z coordinates before you click on the map.

Click the left mouse button in the plot window to write the current coordinates to the Digitized Coordinates window. Continue adding points in this manner. Digitized points appear as temporary small red plus-signs on the map.
When you are finished using the Digitize command, click on any tool button or command, or press the ESC key on the keyboard.
To save the data in the Digitized Coordinates window, click the File | Save As command in the window. You are prompted to save the data as Blanking Files (*.bln) or Data Files (*.dat). Type a File name and click Save to save the data. Click Cancel to not save the data and return to the Digitized Coordinates window.
Click the button in the top right corner of the window to close the Digitized Coordinates dialog. The dialog will stay open until closed in this manner.

Coordinate System Information

If the map that you are digitizing from is referenced with a coordinate system on the Coordinate System page, the digitized .BLN or data file automatically creates a .GSR2 file. The points digitized and the .GSR2 file contains the map's target coordinate system information. This is the map's coordinate system, not the map layer's coordinate system.

If you want to digitize information in a map layer's source coordinate system, you will need to change the map's target Coordinate System information to match the map layer's coordinate system.