VRC Documentation

Appendix F - The .sct2 Sector File Format

Starting with version 1.1, VRC supports two extensions to the standard sector file format. The two new sections are called Regions and Labels. Other than these two new sections, .sct2 files are identical to .sct files.

Regions

Regions are used to define areas on the scope which are filled with a solid color. These filled polygons can be used to depict many different things in a sector such as special-use airspace, airways, ground maps, bodies of water, etc.

To define regions in a .sct2 sector file, create a [REGIONS] section. You can create an unlimited number of regions within the section. Each region consists of a color definition and a series of lat/lon points. A region definition ends when a new region definition begins, or when a new section begins.

Here's an example [REGIONS] section with a single region definition:

[REGIONS]
Grey    N042.27.51.070 W071.17.09.758
        N042.27.51.390 W071.17.14.849
        N042.28.08.310 W071.17.24.907
        N042.28.08.332 W071.17.25.163
        N042.28.09.203 W071.17.24.997
        N042.28.04.609 W071.16.38.186
        N042.28.03.796 W071.16.39.158
        N042.27.53.179 W071.16.40.814
        N042.27.55.692 W071.17.12.498
        N042.27.54.263 W071.17.12.782
        N042.27.53.896 W071.17.09.334

The first line of a region definition contains the color code, followed by the first point on the polygon. Each additional line must start with one or more spaces, followed by the lat/lon for the next point on the polygon.

You do not need to duplicate the start point at the end of the list of points. VRC will automatically close the polygon.

Following is another example [REGIONS] section with multiple region definitions. The third region uses a numeric color code instead of a color code specified by a #define line earlier in the sector file:

[REGIONS]
Grey    N042.27.51.070 W071.17.09.758
        N042.27.51.390 W071.17.14.849
        N042.28.08.310 W071.17.24.907
        N042.28.08.332 W071.17.25.163
        N042.28.09.203 W071.17.24.997
        N042.28.04.609 W071.16.38.186
        N042.28.03.796 W071.16.39.158
        N042.27.53.179 W071.16.40.814
        N042.27.55.692 W071.17.12.498
        N042.27.54.263 W071.17.12.782
        N042.27.53.896 W071.17.09.334
Orange  N042.27.48.816 W071.17.49.520
        N042.27.43.829 W071.17.54.595
        N042.27.42.910 W071.17.52.948
        N042.27.47.929 W071.17.47.903
255     N042.28.06.190 W071.17.03.084
        N042.28.05.308 W071.16.53.951
        N042.28.02.294 W071.16.54.466
        N042.28.03.155 W071.17.03.674

Labels

Labels are simple static text strings drawn at a specified lat/lon on the scope. They can only be one line of text, and they're always drawn in the same font as the navaid names. These labels are useful for identifying various items in the sector such as MVAs, taxiway names, special-use airspace, etc.

To define one or more labels in your .sct2 sector file, add a [LABELS] section. You can define an unlimited number of text labels in this section. Each line creates a new label. Here's an example [LABELS] section:

[LABELS]
"Bogus MOA" N042.27.47.929 W071.17.47.903 MOAColor
"This label is red" N045.00.00.000 W072.00.00.000 255
"C" N046.00.00.000 W072.00.00.000 Taxiway

The line starts with the actual text of the label, which must be enclosed in double quotes. This is followed by the lat/lon for the location where you want the label to be printed. The last field is the color definition for the label. Each label can be a different color.

© Copyright 2005 Ross Alan Carlson - All Rights Reserved