Issue/2518 epicycle (#3195)

* added epicycle asset; updated trailFromEarth period and colors; added FromEarth trails to trail toggle;

---------

Co-authored-by: Alexander Bock <alexander.bock@liu.se>

data/assets/actions/trails/toggle_all_trails.asset

@@ -56,6 +56,7 @@ local ToggleTrails = {
       end
       openspace.setPropertyValue("Scene.*Trail.Renderable.Fade", newFade, 2)
       openspace.setPropertyValue("Scene.*trail.Renderable.Fade", newFade, 2)
+      openspace.setPropertyValue("Scene.*TrailEarth.Renderable.Fade", newFade, 2)
     end
   ]],
   Documentation = "Toggle fade for all trails in the Scene",

data/assets/educational/epicycle.asset

@@ -0,0 +1,79 @@
+asset.require("scene/solarsystem/planets/mercury/trail_earth")
+asset.require("scene/solarsystem/planets/venus/trail_earth")
+asset.require("scene/solarsystem/planets/mars/trail_earth")
+asset.require("scene/solarsystem/planets/jupiter/trail_earth")
+asset.require("scene/solarsystem/planets/saturn/trail_earth")
+asset.require("scene/solarsystem/planets/uranus/trail_earth")
+asset.require("scene/solarsystem/planets/neptune/trail_earth")
+
+
+local FullCycleAction = {
+  Identifier = "os.epicycle.SetFull",
+  Name = "Set full epicycles",
+  Documentation = [[Sets EnableFade to false for all epicycle trails so that 
+    they show the entire period]],
+  Command = [[openspace.setPropertyValue("*TrailEarth.Renderable.Appearance.EnableFade", false)]],
+  GuiPath = "/Trails/Epicycle",
+  IsLocal = false
+}
+
+local FadedCycleAction = {
+  Identifier = "os.epicycle.SetFaded",
+  Name = "Set faded epicycles",
+  Documentation = [[Sets EnableFade to true for all epicycle trails so that 
+    they match the default planet trails]],
+  Command = [[openspace.setPropertyValue("*TrailEarth.Renderable.Appearance.EnableFade", true)]],
+  GuiPath = "/Trails/Epicycle",
+  IsLocal = false
+}
+
+local ShowCyclesAction = {
+  Identifier = "os.epicycle.ShowTrails",
+  Name = "Enable/Show epicycles",
+  Documentation = [[Enables and shows in all epicycle trails]],
+  Command = [[openspace.setPropertyValue("*TrailEarth.Renderable.Enabled", true);
+  openspace.setPropertyValue("*TrailEarth.Renderable.Fade", 1, 2);]],
+  GuiPath = "/Trails/Epicycle",
+  IsLocal = false
+}
+
+local FadeoutCyclesAction = {
+  Identifier = "os.epicycle.HideTrails",
+  Name = "Hide epicycles",
+  Documentation = [[Hides all epicycle trails]],
+  Command = [[openspace.setPropertyValue("*TrailEarth.Renderable.Fade", 0, 2)]],
+  GuiPath = "/Trails/Epicycle",
+  IsLocal = false
+}
+
+
+asset.onInitialize(function()
+  openspace.action.registerAction(FullCycleAction)
+  openspace.action.registerAction(FadedCycleAction)
+  openspace.action.registerAction(ShowCyclesAction)
+  openspace.action.registerAction(FadeoutCyclesAction)
+end)
+
+asset.onDeinitialize(function()
+  openspace.action.removeAction(FadeoutCyclesAction)
+  openspace.action.removeAction(ShowCyclesAction)
+  openspace.action.removeAction(FadedCycleAction)
+  openspace.action.removeAction(FullCycleAction)
+end)
+
+asset.export("FullCycleAction", FullCycleAction.Identifier)
+asset.export("FadedCycleAction", FadedCycleAction.Identifier)
+asset.export("ShowCyclesAction", ShowCyclesAction.Identifier)
+asset.export("FadeoutCyclesAction", FadeoutCyclesAction.Identifier)
+
+
+
+asset.meta = {
+  Name = "Epicycle",
+  Version = "1.0",
+  Description = [[This asset includes the trails of the planets from earth.
+    In addition, it provides some actions for manipulating them.]],
+  Author = "OpenSpace Team",
+  URL = "http://openspaceproject.com",
+  License = "MIT license"
+}

data/assets/scene/solarsystem/planets/jupiter/trail_earth.asset

@@ -15,8 +15,8 @@ local JupiterTrailEarth = {
       Target = coreKernels.ID.Jupiter,
       Observer = coreKernels.ID.Earth
     },
-    Color = { 1.0, 0.5, 0.2 },
-    Period = 224.695,
+    Color = { 0.8, 0.7, 0.7 },
+    Period = 4375.0,
     Resolution = 1000
   },
   Tag = { "planetTrail_solarSystem_alt", "planetTrail_terrestrial_alt" },

data/assets/scene/solarsystem/planets/mars/trail_earth.asset

@@ -14,8 +14,8 @@ local MarsTrailEarth = {
       Target = coreKernels.ID.Mars,
       Observer = coreKernels.ID.Earth
     },
-    Color = { 1.0, 0.5, 0.2 },
-    Period = 224.695,
+    Color = { 0.814, 0.305, 0.220 },
+    Period = 5990.0,
     Resolution = 1000
   },
   Tag = { "planetTrail_solarSystem_alt", "planetTrail_terrestrial_alt" },

data/assets/scene/solarsystem/planets/mercury/trail_earth.asset

@@ -15,8 +15,8 @@ local MercuryTrailEarth = {
       Target = coreKernels.ID.Mercury,
       Observer = coreKernels.ID.Earth
     },
-    Color = { 1.0, 0.5, 0.2 },
-    Period = 224.695,
+    Color = { 0.6, 0.5, 0.5 },
+    Period = 380.0,
     Resolution = 1000
   },
   Tag = { "planetTrail_solarSystem_alt", "planetTrail_terrestrial_alt" },

data/assets/scene/solarsystem/planets/neptune/trail_earth.asset

@@ -15,9 +15,9 @@ local NeptuneTrailEarth = {
       Target = coreKernels.ID.Neptune,
       Observer = coreKernels.ID.Earth
     },
-    Color = { 1.0, 0.5, 0.2 },
-    Period = 224.695,
-    Resolution = 1000
+    Color = { 0.2, 0.5, 1.0 },
+    Period = 60250.0,
+    Resolution = 3000
   },
   Tag = { "planetTrail_solarSystem_alt", "planetTrail_terrestrial_alt" },
   GUI = {

data/assets/scene/solarsystem/planets/saturn/trail_earth.asset

@@ -14,9 +14,9 @@ local SaturnTrailEarth = {
       Target = coreKernels.ID.Saturn,
       Observer = coreKernels.ID.Earth
     },
-    Color = { 1.0, 0.5, 0.2 },
-    Period = 224.695,
-    Resolution = 1000
+    Color = { 0.85, 0.75, 0.51 },
+    Period = 10746.94,
+    Resolution = 3000
   },
   Tag = { "planetTrail_solarSystem_alt", "planetTrail_terrestrial_alt" },
   GUI = {

data/assets/scene/solarsystem/planets/uranus/trail_earth.asset

@@ -14,9 +14,9 @@ local UranusTrailEarth = {
       Target = coreKernels.ID.Uranus,
       Observer = coreKernels.ID.Earth
     },
-    Color = { 1.0, 0.5, 0.2 },
-    Period = 224.695,
-    Resolution = 1000
+    Color = { 0.6, 0.95, 1.0 },
+    Period = 30588.74,
+    Resolution = 3000
   },
   Tag = { "planetTrail_solarSystem_alt", "planetTrail_terrestrial_alt" },
   GUI = {

data/assets/scene/solarsystem/planets/venus/trail_earth.asset

@@ -16,7 +16,7 @@ local VenusTrailEarth = {
       Observer = coreKernels.ID.Earth
     },
     Color = { 1.0, 0.5, 0.2 },
-    Period = 224.695,
+    Period = 2900.0,
     Resolution = 1000
   },
   Tag = { "planetTrail_solarSystem_alt", "planetTrail_terrestrial_alt" },