moved light source to sun.asset, removed light_source.asset

data/assets/examples/celestial_globe.asset

@@ -4,7 +4,7 @@ local sun_transforms = asset.require("scene/solarsystem/sun/transforms")
 local mars = asset.require("scene/solarsystem/planets/mars/mars")
 local earth = asset.require("scene/solarsystem/planets/earth/earth")
 local moon = asset.require("scene/solarsystem/planets/earth/moon/moon")
-local lightsource = asset.require("scene/solarsystem/sun/light_source")
+local sun = asset.require("scene/solarsystem/sun/sun")
 
 local celestial_globe_folder = asset.resource({
   Name = "Celestial Globe",
@@ -49,7 +49,7 @@ function createModel(longitude, latitude, scale, name, parent, group)
         sun_transforms.LightSource
       },
       CastShadow = true,
-      LightSource = lightsource.LightSource.Identifier,
+      LightSource = sun.LightSource.Identifier,
       ShadowGroup = group
     },
     GUI = {
@@ -71,7 +71,8 @@ asset.onInitialize(function()
 end)
 
 asset.onDeinitialize(function()
-  for i = 1, #globeModels do
+  -- Reverse order to deinitialize to avoid dependency issues between nodes
+  for i = #globeModels, 1, -1 do
     openspace.removeSceneGraphNode(globeModels[i].Identifier)
   end
 end)

data/assets/scene/solarsystem/sun/light_source.asset

@@ -1,24 +0,0 @@
-local transforms = asset.require("./transforms")
-
-local LightSource = {
-  Identifier = "sun-directional-lightsource",
-  Parent = transforms.SunIAU.Identifier,
-  Renderable = {
-    Type = "DirectionalLightSource",
-  },
-  GUI = {
-    Name = "Directional Light Source",
-    Path = "/Solar System/Sun",
-    Description = "Shadow-casting directional light source for our Sun"
-  }
-}
-
-asset.onInitialize(function()
-  openspace.addSceneGraphNode(LightSource)
-end)
-
-asset.onDeinitialize(function()
-  openspace.removeSceneGraphNode(LightSource)
-end)
-
-asset.export("LightSource", LightSource)

data/assets/scene/solarsystem/sun/sun.asset

@@ -50,21 +50,34 @@ local SunLabel = {
   }
 }
 
+local LightSource = {
+  Identifier = "sun-directional-lightsource",
+  Parent = transforms.SunIAU.Identifier,
+  Renderable = {
+    Type = "DirectionalLightSource",
+  },
+  GUI = {
+    Name = "Directional Light Source",
+    Path = "/Solar System/Sun",
+    Description = "Shadow-casting directional light source for our Sun"
+  }
+}
 
 asset.onInitialize(function()
   openspace.addSceneGraphNode(Sun)
   openspace.addSceneGraphNode(SunLabel)
+  openspace.addSceneGraphNode(LightSource)
 end)
 
 asset.onDeinitialize(function()
+  openspace.removeSceneGraphNode(LightSource)
   openspace.removeSceneGraphNode(SunLabel)
   openspace.removeSceneGraphNode(Sun)
 end)
 
 asset.export(Sun)
 asset.export(SunLabel)
-
-
+asset.export("LightSource", LightSource)
 
 asset.meta = {
   Name = "Sun",