Merge pull request #1066 from OpenSpace/feature/iss-asset

Feature/iss asset

data/assets/default.profile

@@ -3,6 +3,10 @@
 
 #Asset
 scene/solarsystem/planets/earth/earth	required
+scene/solarsystem/planets/earth/satellites/satellites   required
+
+#Property
+setPropertyValue  {earth_satellites}.Renderable.Enabled false
 
 #Time
 relative	-1d

data/assets/default.scene

@@ -1,6 +1,7 @@
 asset.require('./base')
 
 local earthAsset = asset.require('scene/solarsystem/planets/earth/earth')
+asset.request('scene/solarsystem/planets/earth/satellites/satellites.asset')
 
 asset.onInitialize(function ()
     local now = openspace.time.currentWallTime()
@@ -10,6 +11,8 @@ asset.onInitialize(function ()
     openspace.globebrowsing.goToGeo("Earth", 58.5877, 16.1924, 20000000)
 
     openspace.markInterestingNodes({ "Earth", "Mars", "Moon", "Sun" })
+
+    openspace.setPropertyValue("{earth_satellites}.Renderable.Enabled", false)
 end)
 
 asset.onDeinitialize(function ()

data/assets/scene/solarsystem/planets/earth/satellites/communications/amateur.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Amateur Radio",

data/assets/scene/solarsystem/planets/earth/satellites/communications/experimental.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Experimental",

data/assets/scene/solarsystem/planets/earth/satellites/communications/geostationary.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Geostationary",

data/assets/scene/solarsystem/planets/earth/satellites/communications/globalstar.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "GlobalStar",

data/assets/scene/solarsystem/planets/earth/satellites/communications/gorizont.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Gorizont",

data/assets/scene/solarsystem/planets/earth/satellites/communications/intelsat.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Intelsat",

data/assets/scene/solarsystem/planets/earth/satellites/communications/iridium.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Iridium",

data/assets/scene/solarsystem/planets/earth/satellites/communications/iridium_next.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Iridium NEXT",

data/assets/scene/solarsystem/planets/earth/satellites/communications/molniya.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Molniya",

data/assets/scene/solarsystem/planets/earth/satellites/communications/orbcomm.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Orbcomm",

data/assets/scene/solarsystem/planets/earth/satellites/communications/other_comm.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Other comm",

data/assets/scene/solarsystem/planets/earth/satellites/communications/raduga.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Raduga",

data/assets/scene/solarsystem/planets/earth/satellites/communications/ses.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "SES",

data/assets/scene/solarsystem/planets/earth/satellites/debris/debris_asat.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../debris_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Indian ASAT test Debris",

data/assets/scene/solarsystem/planets/earth/satellites/debris/debris_breezem.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../debris_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Breeze-M Breakup",

data/assets/scene/solarsystem/planets/earth/satellites/debris/debris_fengyun.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../debris_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Fengyun Debris",

data/assets/scene/solarsystem/planets/earth/satellites/debris/debris_iridium33.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../debris_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Iridium 33 Debris",

data/assets/scene/solarsystem/planets/earth/satellites/debris/debris_kosmos2251.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../debris_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Kosmos 2251 Debris",

data/assets/scene/solarsystem/planets/earth/satellites/debris_shared.asset

@@ -1,67 +0,0 @@
-local transforms = asset.require('scene/solarsystem/planets/earth/transforms')
-local assetHelper = asset.require('util/asset_helper')
-
-function downloadTLEFile(sceneAsset, url, name)
-    local identifier = name
-    identifier = identifier:gsub(" ", "")
-    identifier = identifier:gsub("&", "")
-    identifier = identifier:gsub("-", "")
-    return sceneAsset.syncedResource({
-        Name = "Satellite TLE Data (" .. name .. ")",
-        Type = "UrlSynchronization",
-        Identifier = "satellite_tle_data_" .. identifier,
-        Url = url
-    })
-end
-
-local registerSatelliteGroupObjects = function(containingAsset, group, tleFolder, shouldAddDuplicates)
-     local filename = group.Url:match("([^/]+)$")
-     local filenameSansExt = filename:gsub(filename:match("(%.%w+)$"), "")
-
-     local path = tleFolder .. "/" .. filename
-
-    function numLinesInFile(filename)
-        local ctr = 0
-        for _ in io.lines(filename) do ctr = ctr + 1 end
-        return ctr
-    end
-
-    -- Check format of a set of 3 TLE file lines and return nonzero if there is a format error
-    function isValidTLEFileFormat(lineArr)
-        function isEmpty(s) return s == nil or s == '' end
-
-        if isEmpty(lineArr[1]) or isEmpty(lineArr[2]) or isEmpty(lineArr[3]) then
-            return false
-        end
-        if string.sub(lineArr[2], 1, 2) ~= "1 " then
-            return false
-        end
-        if string.sub(lineArr[3], 1, 2) ~= "2 " then
-            return false
-        end
-        return true
-    end
-
-    function debris(title, file, color)
-        return {
-           Identifier = title,
-           Parent = transforms.EarthInertial.Identifier,
-           Renderable = {
-                Type = "RenderableSatellites",
-                Path = file,
-                Segments = 160,
-                Color = color,
-                Fade = 0.5                
-            },
-            GUI = {
-                Path = "/Solar System/Planets/Earth/Satellites"
-           }
-        }
-    end
-
-    local Debris = debris(filenameSansExt, path, group.TrailColor)
-    assetHelper.registerSceneGraphNodesAndExport(containingAsset, { Debris })
-end
-
-asset.export("downloadTLEFile", downloadTLEFile)
-asset.export("registerSatelliteGroupObjects", registerSatelliteGroupObjects)

data/assets/scene/solarsystem/planets/earth/satellites/misc/brightest.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "100 Brightest",

data/assets/scene/solarsystem/planets/earth/satellites/misc/cubesats.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "CubeSat",

data/assets/scene/solarsystem/planets/earth/satellites/misc/iss.asset

@@ -0,0 +1,119 @@
+local assetHelper = asset.require('util/asset_helper')
+local satelliteHelper = asset.require('util/tle_helper')
+local transforms = asset.require('scene/solarsystem/planets/earth/transforms')
+local sunTransforms = asset.require('scene/solarsystem/sun/transforms')
+
+local url = "https://celestrak.com/satcat/tle.php?CATNR=25544"
+local identifier = "ISS"
+local filename = "ISS.txt"
+local nodes = {}
+local tle = satelliteHelper.downloadTLEFile(asset, url, identifier, filename)
+
+local modelsLocation = asset.syncedResource({
+    Name = "ISS Models",
+    Type = "HttpSynchronization",
+    Identifier = "iss_model",
+    Version = 1
+})
+
+local initializeAndAddNodes = function()
+
+  local lineElement = satelliteHelper.makeSingleLineElement(tle, filename)
+  local period = satelliteHelper.getPeriodFromElement(lineElement)
+  local path = tle .. "\\" .. filename
+
+-- TLE data is only relevant in EarthInertial frame which means the model
+-- will inherit some irrelevant rotations from its parent. To get around that
+-- we perform the reverse rotation back to EarthBarycenter frame after applying
+-- the TLE translation
+  local iss = {
+    Identifier = identifier,
+    Parent = transforms.EarthInertial.Identifier,
+    Transform = {
+      Translation = {
+        Type = "TLETranslation",
+        Body = identifier,
+        Observer = transforms.EarthInertial.Identifier,
+        File = path,
+        LineNumber = 1
+      },
+      Rotation = {
+          Type = "SpiceRotation",
+          SourceFrame = "GALACTIC",
+          DestinationFrame = "J2000",
+      }
+    },
+    Tag = { "earth_satellite", "ISS" },
+    GUI = {
+        Path = "/Solar System/Planets/Earth/Satellites/ISS",
+        Hiden = true
+    }
+  }
+
+  local issModel = {
+    Identifier = identifier .. "_model",
+    Parent = iss.Identifier,
+    Transform = {
+      Rotation = {
+        Type = "FixedRotation",
+        Attached = "ISS_model",
+        XAxis = { 1.0, 0.0, 0.0 },
+        XAxisOrthogonal = true,
+        ZAxis = transforms.EarthInertial.Identifier
+      }
+    },
+    Renderable = {
+      Type = "RenderableModel",
+      Geometry = {
+        Type = "MultiModelGeometry",
+        GeometryFile = modelsLocation .. "/iss.obj"
+      },
+      ColorTexture =  modelsLocation .. "/gray.png",
+      LightSources = assetHelper.getDefaultLightSources(sunTransforms.SolarSystemBarycenter.Identifier)
+    },
+    Tag = { "earth_satellite", "ISS" },
+    GUI = {
+      Path = "/Solar System/Planets/Earth/Satellites/ISS"
+    }
+  }
+
+  local issTrail = {
+    Identifier = identifier .. "_trail",
+    Parent = transforms.EarthInertial.Identifier,
+    Renderable = {
+        Type = "RenderableTrailOrbit",
+        Translation = {
+          Type = "TLETranslation",
+          Body = identifier,
+          Observer = transforms.EarthInertial.Identifier,
+          File = path,
+          LineNumber = 1
+        },
+        Color = { 0.9, 0.6715, 0.0 },
+        Fade = 1.5,
+        Period = period,
+        Resolution = 320
+      },
+    Tag = { "earth_satellite", "ISS" },
+    GUI = {
+        Path = "/Solar System/Planets/Earth/Satellites/ISS"
+    }
+  }
+
+  local myNodes = { iss, issModel, issTrail }
+
+  for _, node in ipairs(myNodes) do
+    openspace.addSceneGraphNode(node)
+  end
+
+  return myNodes
+end
+
+asset.onInitialize(function ()
+  nodes = initializeAndAddNodes()
+end)
+
+asset.onDeinitialize(function ()
+  openspace.removeSceneGraphNode(nodes[3].Identifier) -- Removing trail
+  openspace.removeSceneGraphNode(nodes[1].Identifier) -- Removing ISS and model recursively
+end)

data/assets/scene/solarsystem/planets/earth/satellites/misc/military.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Military",

data/assets/scene/solarsystem/planets/earth/satellites/misc/other.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Other",

data/assets/scene/solarsystem/planets/earth/satellites/misc/radar.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Radar Calibration",

data/assets/scene/solarsystem/planets/earth/satellites/misc/spacestations.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "SpaceStations",

data/assets/scene/solarsystem/planets/earth/satellites/misc/tle-new.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Last 30 Days",

data/assets/scene/solarsystem/planets/earth/satellites/navigation/beidou.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Beidou",

data/assets/scene/solarsystem/planets/earth/satellites/navigation/galileo.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Galileo",

data/assets/scene/solarsystem/planets/earth/satellites/navigation/glosnass.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Glosnass",

data/assets/scene/solarsystem/planets/earth/satellites/navigation/gps.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "GPS",

data/assets/scene/solarsystem/planets/earth/satellites/navigation/musson.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Russian LEO Navigation",

data/assets/scene/solarsystem/planets/earth/satellites/navigation/nnss.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Navy Navigation Satellite System",

data/assets/scene/solarsystem/planets/earth/satellites/navigation/sbas.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Satellite Based Augmentation System",

data/assets/scene/solarsystem/planets/earth/satellites/satellites_interesting.asset

@@ -2,4 +2,5 @@ asset.request('./misc/brightest')
 asset.request('./communications/geostationary')
 asset.request('./navigation/gps')
 asset.request('./misc/spacestations')
+asset.request('./misc/iss')
 asset.request('./misc/tle-new')

data/assets/scene/solarsystem/planets/earth/satellites/satellites_shared.asset

@@ -1,68 +0,0 @@
-local transforms = asset.require('scene/solarsystem/planets/earth/transforms')
-local assetHelper = asset.require('util/asset_helper')
-
-function downloadTLEFile(sceneAsset, url, name)
-    local identifier = name
-    identifier = identifier:gsub(" ", "")
-    identifier = identifier:gsub("&", "")
-    identifier = identifier:gsub("-", "")
-    return sceneAsset.syncedResource({
-        Name = "Satellite TLE Data (" .. name .. ")",
-        Type = "UrlSynchronization",
-        Identifier = "satellite_tle_data_" .. identifier,
-        Url = url
-    })
-end
-
-local registerSatelliteGroupObjects = function(containingAsset, group, tleFolder, shouldAddDuplicates)
-     local filename = group.Url:match("([^/]+)$")
-     local filenameSansExt = filename:gsub(filename:match("(%.%w+)$"), "")
-
-     local path = tleFolder .. "/" .. filename
-
-    function numLinesInFile(filename)
-        local ctr = 0
-        for _ in io.lines(filename) do ctr = ctr + 1 end
-        return ctr
-    end
-
-    -- Check format of a set of 3 TLE file lines and return nonzero if there is a format error
-    function isValidTLEFileFormat(lineArr)
-        function isEmpty(s) return s == nil or s == '' end
-
-        if isEmpty(lineArr[1]) or isEmpty(lineArr[2]) or isEmpty(lineArr[3]) then
-            return false
-        end
-        if string.sub(lineArr[2], 1, 2) ~= "1 " then
-            return false
-        end
-        if string.sub(lineArr[3], 1, 2) ~= "2 " then
-            return false
-        end
-        return true
-    end
-
-    function satellites(title, file, color)
-        return {
-           Identifier = title,
-           Parent = transforms.EarthInertial.Identifier,
-           Renderable = {
-                Type = "RenderableSatellites",
-                Path = file,
-                Segments = 120,
-                Color = color,
-                Fade = 0.5
-            },
-            --Tag = { "earth_satellite_" .. group, "earth_satellite_" .. group .. "_trail"},
-            GUI = {
-                Path = "/Solar System/Planets/Earth/Satellites"
-           }
-        }
-    end
-
-    local SatelliteBatch = satellites(filenameSansExt, path, group.TrailColor)
-    assetHelper.registerSceneGraphNodesAndExport(containingAsset, { SatelliteBatch })
-end
-
-asset.export("downloadTLEFile", downloadTLEFile)
-asset.export("registerSatelliteGroupObjects", registerSatelliteGroupObjects)

data/assets/scene/solarsystem/planets/earth/satellites/science/education.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Education",

data/assets/scene/solarsystem/planets/earth/satellites/science/engineering.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Engineering",

data/assets/scene/solarsystem/planets/earth/satellites/science/geodetic.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Geodect",

data/assets/scene/solarsystem/planets/earth/satellites/science/spaceearth.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Space & Earth Science",

data/assets/scene/solarsystem/planets/earth/satellites/weather/argos.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "ARGOS",

data/assets/scene/solarsystem/planets/earth/satellites/weather/dmc.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Disaster Monitoring",

data/assets/scene/solarsystem/planets/earth/satellites/weather/earth_resources.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Earth Resources",

data/assets/scene/solarsystem/planets/earth/satellites/weather/goes.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "GOES",

data/assets/scene/solarsystem/planets/earth/satellites/weather/noaa.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "NOAA",

data/assets/scene/solarsystem/planets/earth/satellites/weather/planet.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Planet",

data/assets/scene/solarsystem/planets/earth/satellites/weather/sarsat.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Search & Rescue (SARSAT)",

data/assets/scene/solarsystem/planets/earth/satellites/weather/spire.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Spire",

data/assets/scene/solarsystem/planets/earth/satellites/weather/tdrss.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Tracking and Data Relay Satellite System (TDRSS)",

data/assets/scene/solarsystem/planets/earth/satellites/weather/weather.asset

@@ -1,5 +1,5 @@
 local assetHelper = asset.require('util/asset_helper')
-local shared = asset.require('../satellites_shared')
+local shared = asset.require('util/tle_helper')
 
 local group = {
     Title = "Weather",

data/assets/util/tle_helper.asset

@@ -0,0 +1,110 @@
+local transforms = asset.require('scene/solarsystem/planets/earth/transforms')
+local assetHelper = asset.require('util/asset_helper')
+
+function downloadTLEFile(sceneAsset, url, name, filename)
+    local identifier = name
+    identifier = identifier:gsub(" ", "")
+    identifier = identifier:gsub("&", "")
+    identifier = identifier:gsub("-", "")
+
+    local urlSyncTable = {
+        Name = "Satellite TLE Data (" .. name .. ")",
+        Type = "UrlSynchronization",
+        Identifier = "satellite_tle_data_" .. identifier,
+        Url = url
+    }
+
+    if (filename ~= '')  then
+        urlSyncTable.Filename = filename
+    end
+
+    return sceneAsset.syncedResource(urlSyncTable)
+end
+
+-- Check format of a set of 3 TLE file lines and return nonzero if there is a format error
+function isValidTLEFileFormat(lineArr)
+    function isEmpty(s) return s == nil or s == '' end
+
+    if isEmpty(lineArr[1]) or isEmpty(lineArr[2]) or isEmpty(lineArr[3]) then
+        return false
+    end
+    if string.sub(lineArr[2], 1, 2) ~= "1 " then
+        return false
+    end
+    if string.sub(lineArr[3], 1, 2) ~= "2 " then
+        return false
+    end
+    return true
+end
+
+local makeSingleLineElement = function(tle, filename)
+  local path = tle .. "\\" .. filename
+  local file = io.open(path, "r")
+  assert(file, "File not found: " .. path)
+
+    local line = {
+    file:read('*l'), --title line
+    file:read('*l'),
+    file:read('*l')
+  }
+
+  assert(isValidTLEFileFormat(line), "TLE file syntax error on line " .. 1 .. ": " .. path)
+
+  -- Trim string
+  line[1] = line[1]:gsub("^%s*(.-)%s*$", "%1")
+  line[1] = line[1]:gsub("%s+", "_")
+  line[1] = line[1]:gsub("[%-()]", "")
+  --local title = line[1]
+
+  return line
+end
+
+function numLinesInFile(filename)
+    local ctr = 0
+    for _ in io.lines(filename) do ctr = ctr + 1 end
+    return ctr
+end
+
+local getPeriodFromElement = function(element)
+  -- Get period from correct location of the string
+  local per = tonumber(string.sub(element[3], 53, 63))
+  -- Trail for 2x a single revolution
+  per = 1.0 / per
+
+  return per
+end
+
+function satellites(title, file, color, group)
+    return {
+       Identifier = title,
+       Parent = transforms.EarthInertial.Identifier,
+       Renderable = {
+            Type = "RenderableSatellites",
+            Path = file,
+            Segments = 120,
+            Color = color,
+            Fade = 1.5
+        },
+        Tag = { "earth_satellites" },
+        GUI = {
+            Path = "/Solar System/Planets/Earth/Satellites"
+       }
+    }
+end
+
+local registerSatelliteGroupObjects = function(containingAsset, group, tleFolder, shouldAddDuplicates)
+    local filename = group.Url:match("([^/]+)$")
+    local filenameSansExt = filename:gsub(filename:match("(%.%w+)$"), "")
+
+    local path = tleFolder .. "/" .. filename
+
+    local SatelliteBatch = satellites(filenameSansExt, path, group.TrailColor, group)
+    assetHelper.registerSceneGraphNodesAndExport(containingAsset, { SatelliteBatch })
+end
+
+asset.export("downloadTLEFile", downloadTLEFile)
+asset.export("isValidTLEFileFormat", isValidTLEFileFormat)
+asset.export("numLinesInFile", numLinesInFile)
+asset.export("makeSingleLineElement", makeSingleLineElement)
+asset.export("getPeriodFromElement", getPeriodFromElement)
+asset.export("registerSatelliteGroupObjects", registerSatelliteGroupObjects)

modules/space/rendering/renderablesatellites.cpp

@@ -71,6 +71,11 @@ namespace {
         "Color",
         "This value determines the RGB main color for the lines and points of the trail."
     };
+    constexpr openspace::properties::Property::PropertyInfo TrailFadeInfo = {
+        "TrailFade",
+        "Trail Fade",
+        "This value determines how fast the trail fades and is an appearance property. "
+    };
     
     constexpr const char* KeyFile = "Path";
     constexpr const char* KeyLineNum = "LineNumber";
@@ -321,15 +326,24 @@ RenderableSatellites::RenderableSatellites(const ghoul::Dictionary& dictionary)
     if (dictionary.hasKeyAndValue<glm::vec3>(LineColorInfo.identifier)) {
         _appearance.lineColor = dictionary.value<glm::vec3>(LineColorInfo.identifier);
     }
-    if (dictionary.hasKeyAndValue<double>("FadeInfo")) {
+    if (dictionary.hasKeyAndValue<double>(TrailFadeInfo.identifier)) {
         _appearance.lineFade = static_cast<float>(
-            dictionary.value<double>("FadeInfo")
+            dictionary.value<double>(TrailFadeInfo.identifier)
         );
     }
     else {
         _appearance.lineFade = 20;
     }
 
+    if (dictionary.hasKeyAndValue<double>(LineWidthInfo.identifier)) {
+        _appearance.lineWidth = static_cast<float>(
+            dictionary.value<double>(LineWidthInfo.identifier)
+        );
+    }
+    else {
+        _appearance.lineWidth = 2.0;
+    }
+
     auto reinitializeTrailBuffers = [this]() {
         initializeGL();
     };

modules/sync/syncs/urlsynchronization.cpp

@@ -43,8 +43,10 @@ namespace {
     constexpr const char* KeyIdentifier = "Identifier";
     constexpr const char* KeyOverride = "Override";
     constexpr const char* KeyUseHash = "UseHash";
+    constexpr const char* KeyFilename = "Filename";
 
     constexpr const char* TempSuffix = ".tmp";
+    constexpr const char* FileSuffix = ".txt";
 } // namespace
 
 namespace openspace {
@@ -90,6 +92,13 @@ documentation::Documentation UrlSynchronization::Documentation() {
                 "circumstances. If this is not desired, the URLSynchronization use the "
                 "bare directory name alone if this value is 'false'. If this value is "
                 "'false', the identifier has to be specified."
+            },
+            {
+                KeyFilename,
+                new StringVerifier,
+                Optional::Yes,
+                "Optional to provide filename to override the one which is otherwise "
+                "automatically created from the url. "
             }
         }
     };
@@ -117,6 +126,14 @@ UrlSynchronization::UrlSynchronization(const ghoul::Dictionary& dict,
         }
     }
 
+    if (dict.hasValue<std::string>(KeyFilename)) {
+        _filename = dict.value<std::string>(KeyFilename);
+        std::size_t foundExt = _filename.find(FileSuffix);
+        if (foundExt == std::string::npos) {
+            _filename += FileSuffix;
+        }
+    }
+
     bool useHash = true;
     if (dict.hasValue<bool>(KeyUseHash)) {
         useHash = dict.value<bool>(KeyUseHash);
@@ -181,11 +198,22 @@ void UrlSynchronization::start() {
         std::vector<std::unique_ptr<AsyncHttpFileDownload>> downloads;
 
         for (const std::string& url : _urls) {
-            const size_t lastSlash = url.find_last_of('/');
-            const std::string filename = url.substr(lastSlash + 1);
 
+            if (_filename.empty()) {
+                const size_t lastSlash = url.find_last_of('/');
+                std::string lastPartOfUrl = url.substr(lastSlash + 1);
+
+                // We can not create filenames with questionmarks
+                lastPartOfUrl.erase(std::remove(lastPartOfUrl.begin(), lastPartOfUrl.end(), '?'), lastPartOfUrl.end());
+
+                std::size_t foundExt = lastPartOfUrl.find(FileSuffix);
+                if (foundExt == std::string::npos) {
+                    lastPartOfUrl += FileSuffix;
+                }
+                _filename = lastPartOfUrl;
+            }
             std::string fileDestination = directory() +
-                ghoul::filesystem::FileSystem::PathSeparator + filename + TempSuffix;
+                ghoul::filesystem::FileSystem::PathSeparator + _filename + TempSuffix;
 
             std::unique_ptr<AsyncHttpFileDownload> download =
                 std::make_unique<AsyncHttpFileDownload>(

modules/sync/syncs/urlsynchronization.h

@@ -58,6 +58,7 @@ private:
     bool _forceOverride = false;
     std::string _synchronizationRoot;
     std::string _identifier;
+    std::string _filename;
 
     std::atomic_bool _nTotalBytesKnown = false;
     std::atomic_size_t _nTotalBytes = 0;