Colour Legend Bar

When designing a map that includes a grid, you may want to add a colour bar based on the grid. You can do this quickly using the interactive functionality available through the Colour Legend Bar tool (geogxnet.dll(Geosoft.GX.Map.ColourBar;Run)*) and create a horizontal or vertical colour bar for a colour grid or a colour-shaded grid image.

The tool can be accessed from the following locations:

  • The Grid and Image > Display on Map menu
  • The Map Tools > Symbols menu
  • The Section Tools menu
  • The Euler 3D > Plot Solution Symbols menu with the Grav/Mag Interpretation extension

Colour Legend Bar dialog options

Data layer

Select the data layer to use to generate the colour legend bar. The colour zones in the legend bar will be based on the selected AGG/data layer.

To add a colour legend bar, a map must include a view/agg/layer name for the primary colour bar ITR.

Script Parameter: COLORBAR.AGG

Second data layer

Optional secondary colour layer, generally intended for adding shading to the colour bar for a shaded-colour image. The secondary colour scheme is blended horizontally within to the primary colour scheme.

To plot only the primary colour scheme of a shaded colour grid leave this entry blank.

Script Parameter: COLORBAR.AGG2

Title

Colour bar title, generally referring to the grid it represents.

Script Parameter: COLORBAR.TITLE

Sub-title 1 & 2

Up to two additional lines can be used to further elaborate on the data colour distribution, such as defining the data units.

Script Parameter: COLORBAR.SUBTITLE

Script Parameter: COLORBAR.SUBTITLE2

Bar orientation

The colour bar can be displayed vertically [0] or horizontally [1], to best suit the map layout.

Script Parameter: COLORBAR.BAR_ORIENTATION [0-Vertical |1 - Horizontal]

X & Y location (mm)

 

Location of the centre of the colour bar from the lower left corner of the map, in plot (Base) units of millimetres.

Script Parameter: COLORBAR.X & Y

[Locate]

Click the Locate button to interactively select the desired colour bar location (lower-left corner of the bar) on your map.

[More]

Click the More button to display additional parameters.

Size Definition

Title location

Location of the Title relative to the colour bar.

Script Parameter: COLORBAR.TITLELOC [1- Below & Below centred | 7 - Above & Above centred | 6 - Above left |0 - Below Left]

Title text size (mm)

Specify the title text size in millimetres.

Script Parameter: COLORBAR.TITLE_SIZE

Sub-title text size (mm)

Specify the sub-title text size in millimetres.

Script Parameter: COLORBAR.SUBTITLE_SIZE

Label text size (mm)

Specify the label text size in millimetres.

Script Parameter: COLORBAR.ANNSIZE

Label decimals

Specify the number of decimals of the annotated values.

Script Parameter: COLORBAR.DECIMALS

Bar height / width (mm)

Specify the smallest dimension of the colour bar. Depending on the bar orientation, this parameter will refer to width or height.

Script Parameter: COLORBAR.WIDTH

Cell width / height (mm)

Specify the dimension of the colour bar subdivisions. Depending on the bar orientation, this parameter will refer to width or height.

Script Parameter: COLORBAR.HEIGHT

Minimum gap between labels (mm)

Specify the distance between annotations. By default, annotations that over-print will be dropped. If the default gap is not satisfactory, then provide this parameter. If the Maximum height is set, and the product of the colour cell height and the number of zones exceeds the maximum height, then this value will be reduced to avoid over-printing.

Script Parameter: COLORBAR.MINIMUM_GAP

Maximum bar height (mm)

If specified, the total height of the colour bar is limited to this value. This parameter overrides the cell size entry.

Script Parameter: COLORBAR.MAXHEIGHT

Annotations

Division style

The colour scheme can be optionally subdivided by separators. The separator can be a solid line (default) or a tick.

Script Parameter: COLORBAR.DIVISIONS [ 0 - None |1 - Solid | 2 - Tick]

Post

You can post annotations by grid values or percentile breaks.

If the option Percentiles is selected, the % sign will be added to the colour bar annotations on the map.

Script Parameter: COLORBAR.POST [ 0-Value |1 - Percentile]

Post end value/percentile

Check this box to post the minimum and maximum of the data range at the two ends of the colour bar.

Script Parameter: COLORBAR.POST_END_VALUE [ 0 - No |1 - Yes]

Minimum value/percentile
Maximum value/percentile

If post by Values is selected, these entries will be populated with the minimum and maximum values of the data distribution. When Post end value is checked, you can adjust these values to cover a smaller range or to round them off.

The end values of the colour bar on the map will be annotated with the same number of significant digits as the rest of the annotations.

If post by Percentiles is selected, the entries are not editable and will default to a first and last value of 0 and 100 respectively.

Script Parameters:

COLORBAR.MINIMUM_END_VALUE

COLORBAR.MAXIMUM_END_VALUE

Label orientation

The labels are annotated horizontally by default. When plotting a horizontal colour bar, the use of vertical annotation may be preferable for better clarity.

Script Parameter: COLORBAR.LABEL_ORIENTATION [0 - Horizontal | 1 - Vertical]

Annotate

The annotation can be placed to the left or to the right of a vertical bar and above or below a horizontal bar.

Script Parameter: COLORBAR.ANNOTATION_SIDE [0 - left | 1 - right]

Location

You may opt to annotate the colour legend at:

  • the boundaries between colours: At colour break (default).
  • equal data intervals: Custom intervals.
  • user defined intervals: Exact intervals.

Script Parameter: COLORBAR.ANNO_LOCATION [0 - at colour break| 1 - custom intervals| 2 - exact intervals]

Coarse interval &
Fine interval

If the Custom intervals option has been selected above, the contextual entries, Coarse interval and Fine interval become available.

You must specify the coarse interval; however, the fine interval is optional, and it allows for further gradation of the colour bar annotation.

The drop down list of the Fine interval is restricted to 1/2, 1/4, 1/5, and 1/10 of the Coarse interval.

In this case, the grid summary statistics (minimum, maximum, mean value, standard deviation) are also displayed to assist you with choosing the two intervals.

Script Parameters:

COLORBAR.FIXED_INTERVAL

COLORBAR.FIXED_MINOR_INTERVAL

Interval filename

If the option Exact intervals has been selected above, you will be prompted for the file containing the interval (bin) values. The values should be either comma separated on one line or one value per line.

If the number of bins (in the colour table) does not match the number of supplied colour levels (intervals), then an error message is displayed.

Check the minimum/maximum values of the intervals file against the minimum/maximum values of the grid to make sure the two ranges overlap.

You can set the exact intervals to be further apart in the low (or high) values at the expense of seeing more detail (smaller intervals) in the high (or low) values.

Script Parameter: COLORBAR.EXACTINTERVAL_FILE

*The GX tool will search in the "...\Geosoft\Desktop Applications \gx" folder. The GX.Net tools, however, are embedded in the geogxnet.dll located in the "...\Geosoft\Desktop Applications \bin" folder. If running this GX interactively, bypassing the menu, first change the folder to point to the "bin" folder, then supply the GX.Net tool in the specified format.