button. The Graticule and Grid Designer dialog opens.To place a graticule or a grid on the poject, click the Map | Graticule and Grid command or click the button. The Graticule and Grid Designer dialog opens.
The Graticule page contains the options for displaying and labelling the latitude and longitude lines.
Graticule lines are lines of constant longitude (X coordinate) or latitude (Y coordinate). Longitude lines are also called meridians, and latitude lines are also called parallels. The grid feature allows you to display the Cartesian units of the projection or the Cartesian units if no projection is displayed.
For projected coordinates, the graticule lines can curve to follow the projection (for example, on an Albers projection), or can show different spacing in the north-south dimension (for example, on a Miller projection). For maps using a latitude/longitude coordinate system or a Cartesian coordinate system, a rectangular graticule or grid is drawn.
Didger plots the graticule on a layer named Graticule and the grid on a layer named Grid. The layers can be moved, deleted, or rearranged in the Layer Manager. Multiple graticules and grids can be created in Didger by renaming the existing Graticule or Grid layer. Then, a new grid or graticule can be added by clicking the Map | Graticule and Grid command.
The individual graticule or grid lines can be edited by clicking on the line in the plot window and editing the properties in the Property Manager. If anything is added to the Graticule or Grid layer, it is deleted if the graticule or grid is altered.
A grid can be curved if the projection is changed after the grid was initially created. Consider that a typical USGS 7.5 topographic map shows both State Plane and UTM grid locations on the map. You can create this same type of map in Didger by first creating a grid for the UTM coordinates, renaming the Grid layer to Grid-UTM, reprojecting the project to State Plane coordinates, creating a new grid for the State Plane coordinates. Make sure to rename the initial grid layer, so Didger does not overwrite the first UTM grid.
Graticule lines (left) follow the curves of the projection. Grid
lines (right) show the underlying Cartesian units of the projection.
The Graticule and Grid Designer dialog is organized into two pages, a Graticule page and a Grid page. Most of the options on the two pages are the same. The Graticule page contains options for displaying and labeling the latitude and longitude lines. The Grid page contains options for displaying and labelling grid lines in any units, other than latitude and longitude.
Check the box next to Longitude (X) or Latitude (Y) on the Graticule page to display lines of constant latitude or longitude in the project. Check the box next to the Easting (X) or Northing (Y) on the Grid page to display lines of constant X or Y in the project.
Both pages contain two columns of information. The first column it contains options for lines of constant longitude (meridians) or X lines. The second column it contains the same options for lines of constant latitude (parallels) or Y lines.
On the Grid page, the Grid Units option controls the units used for the Start, End, and Increment values. To change the units, click on the existing option and select the desired units from the list.
The Start and End options contain the range of values that the grid or graticule are drawn. The line starts at the Start minimum value and ends at the End maximum value. To change either the Start or End values, highlight the existing value and type in the desired value. The values are in latitude or longitude on the Graticule page and in Grid Units on the Grid page.
The Increment option controls how often lines are drawn. The first line is drawn at the Start value. The second line is drawn at the Start value plus the Increment value. To change the Increment value, highlight the existing value and type in the desired value. The values are in latitude or longitude on the Graticule page and in Grid Units on the Grid page. If lines should be drawn every 1000 units, change the Increment to 1000 on the Grid tab.
Click the Line Style button to open the Line Attributes dialog. The line Style, Color, and Width can be changed. Click OK in the Line Attributes dialog to return to the Graticule and Grid Designer dialog.
The Show Ticks row contains the Show X and Show Y options. Check the box next to the Show X or Show Y option to display tick marks along the graticule or grid line. Uncheck the box to remove tick marks along the graticule or grid.
The Tick Size/Label Offset row contains the size of the tick mark. The same size is used for the determining how far the label is offset from the tick mark. To change the value, highlight the existing value and type a new value. Alternatively, click the 
to increase or decrease the value. The value is in page units (inches or centimeters).
The Label Frequency controls how many graticule or grid lines display labels. Setting the Label Frequency to any value other than 1 skips graticule or grid lines. For example, if the Label Frequency is set to three, every third line contains a label. To change the value, highlight the existing number and type a new number. Alternatively, click the to increase or decrease the value. Setting the Label Frequency to zero removes all labels from the graticule or grid. Setting the value to one displays labels for every graticule or grid.
The Label Font sets the font properties used for the graticule or grid line label. Click the Font button to open he Font Attributes dialog where you can define the text characteristics to use for the labels. The Face, Points, Style, Color, and Opacity can be changed for the labels. Click OK in the Font Attributes dialog to return to the Graticule and Grid Designer dialog.
The Show Labels options determines where labels are displayed along the graticule or grid line. Check the box next to Start to display labels along the Start value lines. These are on the left and bottom for most projects. Check the box next to End to display labels along the End value lines. These are on the right and top for most projects. When neither the box for Start nor End is checked, no labels are displayed.
The Numeric Display Format option determines the number of decimal places to display on each graticule or grid. Values range between zero and nine. To change the value, highlight the existing number and type a new number. Alternatively, click the to increase or decrease the value.
The Label Angle option sets the angle labels are displayed. A value of zero has horizontal labels, with the number starting on the left. A value of 90 has vertical labels, with the number starting at the bottom. A value of -180 or 180 has values horizontal, with the number starting on the right and displayed upside down. A value of -90 or 270 has vertical labels, with the number starting at the top. Values are in degrees, ranging between -360 and 360. To change the value, highlight the existing number and type a new number. Alternatively, click the to increase or decrease the value.
Check the box next to Use Default to set the Label Angle option back to the default rotation. This is 90 for X values and 0 for Y values.
A text string can be displayed before each label using the Label Prefix box. For example, a "$" could be used as a prefix. Type the text exactly as you want it to appear in the Label Prefix box.
A text string can be displayed after each label using the Label Suffix box. For example, a "°" could be used as a suffix. Type the text exactly as you want it to appear in the Label Suffix box.
To display the degree symbol, copy the symbol from the Windows Character Map or click in the box and press and hold the ALT key on the keyboard. Type 0176 on the numeric keypad. Release the ALT key and the degree sign will appear.
Click the Defaults button at the bottom of the dialog to change the numeric values back to the program defaults.
Click OK to apply the settings and close the dialog. Click Cancel to close the dialog without making changes. Click Apply to apply the settings and keep the dialog open.
See Also
Introduction to Map Projections