Globe Layers

You can customize the display of any CelestialObject (such as the Earth or Moon) in FreeFlyer through the CelestialObject.Globe child object. The globe options let you control the display of the surface textures, planetary atmosphere, coastlines, political boundaries, and custom user-specified lines or location markers. The globe options are organized into the SurfaceLayer, AtmosphereLayer, BoundaryLayers, LineLayers, and LocationLayers as described below.

The following Sample Mission Plans (included with your FreeFlyer installation) demonstrate customized globe layers:

Generating Output Samples

•EntryFootprintWithCoastlineOffsets

•Globe Layers

•Import View Configuration

Working with Globe Layers

You can access the globe options of any built-in or user-created CelestialObject as shown below:

You can also create a new GlobeOptions object, customize it, and assign it to a CelestialObject.Globe:

GlobeOptions customizedEarthGlobe;

// Start by getting the values of the default Earth globe

customizedEarthGlobe = Earth.Globe;

// Change any properties of the globe

customizedEarthGlobe.AtmosphereLayer.UseCloudMap = 0;

// Assign it back to be used by the Earth

Earth.Globe = customizedEarthGlobe;

If you want to display the globe for a CelestialObject differently in different windows (such as a 2D map vs. a 3D view), you can change how the globe is displayed in a single ViewWindow, as shown below. This will override the CelestialObject.Globe settings for that window only.

ViewWindow vw();

vw.SetCelestialObjectGlobeOptions(Earth.ObjectId, customizedEarthGlobe);

Surface Layer

The CelestialObject.Globe.SurfaceLayer lets you control the day and night textures as well as the specular reflections and bump texture. The default textures for the built-in CelestialObjects can be changed through your User Preferences.

// Use high-resolution textures

Earth.Globe.SurfaceLayer.DaytimeImageFilename = FF_Preferences.FreeFlyerEXEPath + "Images\earth_base_very_high.jpg";

Earth.Globe.SurfaceLayer.NighttimeImageFilename = FF_Preferences.FreeFlyerEXEPath + "Images\earth_night_very_high.jpg";

Atmosphere Layer

The CelestialObject.Globe.AtmosphereLayer lets you control the cloud texture and the rendering of atmosphere effects.

// Use high-resolution texture

Earth.Globe.AtmosphereLayer.CloudMapImageFilename = FF_Preferences.FreeFlyerEXEPath + "Images\earth_clouds_very_high.jpg";

BoundaryLayers are used to render coastlines and coastline offsets in FreeFlyer. Use the following script to turn on coastlines:

Earth.Globe.NumberOfBoundaryLayers = 1;

Earth.Globe.BoundaryLayers[0].Label = "Coastlines";

Earth.Globe.BoundaryLayers[0].ImageFilename = FF_Preferences.FreeFlyerEXEPath + "Images\earth_coastlines_very_high.png";

// All coastline files included with FreeFlyer must be used with a distance bias of 0.9

Earth.Globe.BoundaryLayers[0].DistanceBias = 0.9;

You can customize the display of the coastline border color, opacity, and line width. You can also fill the land areas with a solid color, and customize the color and opacity.

You can draw up to 10 coastline offsets on a BoundaryLayer. The following script demonstrates how to draw 2 coastline offset borders at distances of 50 and 200 km. Note that the coastline offset data files delivered with FreeFlyer allow coastline offsets to be drawn at distances of up to 500 km.

// All coastline files included with FreeFlyer must be used with a maximum offset border distance of 500 km

Earth.Globe.BoundaryLayers[0].MaximumOffsetBorderDistance = 500;

Earth.Globe.BoundaryLayers[0].NumberOfOffsetBorders = 2;

Earth.Globe.BoundaryLayers[0].OffsetBorderDistances = {50, 200};

Earth.Globe.BoundaryLayers[0].OffsetBorderColors = {ColorTools.LightSkyBlue, ColorTools.LightCyan};

LineLayers can be used to render political boundaries such as state and country borders. They can also be used to render any user-specified latitude/longitude datasets on the surface of any CelestialObject. For example, they can be used to render landing zones, reentry footprints, safety corridors, destruct lines, regions of scientific interest, etc. Note that LineLayers are used for visualization only. For visibility analysis, see the Coverage and Contact Analysis guide.

The latitude/longitude points that make up a LineLayer can be read in from a binary file format, or specified through script.

To turn on the display of state and country boundaries, use the following script:

Earth.Globe.NumberOfLineLayers = 2;

Earth.Globe.LineLayers[0].Label = "Country Borders";

Earth.Globe.LineLayers[0].LineDataFilename = FF_Preferences.FreeFlyerEXEPath + "data\borders_global_countries.dat";

Earth.Globe.LineLayers[1].Label = "US State Borders";

Earth.Globe.LineLayers[1].LineDataFilename = FF_Preferences.FreeFlyerEXEPath + "data\borders_US_states.dat";

Earth.Globe.LineLayers[0].LineWidth = 2;

Earth.Globe.LineLayers[0].Color = ColorTools.PeachPuff;

Earth.Globe.LineLayers[1].LineWidth = 2;

Earth.Globe.LineLayers[1].Color = ColorTools.LightGreen;

To specify the latitude/longitude points of the line layers through FreeFlyer script, use the following syntax:

Earth.Globe.NumberOfLineLayers = 3;

Earth.Globe.LineLayers[2].Label = "Colorado";

Earth.Globe.LineLayers[2].NumberOfDataPoints = 5;

Earth.Globe.LineLayers[2].Latitude = {37, 37, 41, 41, 37};

Earth.Globe.LineLayers[2].Longitude = {-102.03, -109.03, -109.03, -102.03, -102.03};

// Segments are used to indicate any line breaks in the data

Earth.Globe.LineLayers[2].NumberOfLineSegments = 1;

Earth.Globe.LineLayers[2].SegmentLengths = 5;

LocationLayers can be used to render location markers and names, such as for cities, state or country names, landing sites, imaging targets, etc. Note that LocationLayers are used for visualization only. For visibility analysis, see the Coverage and Contact Analysis guide.

Earth.Globe.NumberOfLocationLayers = 1;

Earth.Globe.LocationLayers[0].Label = "Cities of Interest";

Earth.Globe.LocationLayers[0].NumberOfLocations = 3;

Earth.Globe.LocationLayers[0].LocationName = {"New York City", "Houston", "Los Angeles"};

Earth.Globe.LocationLayers[0].LocationLatitude = {40.7128, 29.7604, 34.0522};

Earth.Globe.LocationLayers[0].LocationLongitude = {-74.0059, -95.3698, -118.2437};

You can customize the color and size of the location markers, as well as the font used to display the location name. You can also turn on/off the location markers or names separately.

Earth.Globe.LocationLayers[0].Color = ColorTools.Yellow;

Earth.Globe.LocationLayers[0].Font.Bold = 1;

Earth.Globe.LocationLayers[0].Font.Size = 14;

Earth.Globe.LocationLayers[0].MarkerSize = 8;

The View Output Properties menu lets you configure the display of objects in any view in FreeFlyer's output screen. Simply right-click in any view and select "Open Properties Editor." You can configure the display settings for any CelestialObject's globe layers through the View Output Properties menu by selecting the CelestialObject (e.g. Earth) under the list of Objects, as shown below.