Move helper lua functions for script scheduling to scripts/common.lua

scripts/common.lua

@@ -4,6 +4,10 @@ helper = {}
 helper.renderable = {}
 helper.property = {}
 
+-- These helpers are for scheduling lua scripts
+-- See class ScriptScheduler and ScheduledScript for reference
+helper.scheduledScript = {} 
+
 -- Function that sets the most common key bindings that are common to most (all?)
 -- scenes
 helper.setCommonKeys = function()
@@ -70,3 +74,21 @@ helper.renderable.toggle = function(renderable)
     return helper.property.invert(renderable .. ".renderable.enabled")
 end
 
+-- Function that returns the string that sets the enabled property of <renderable> to <enabled>
+helper.renderable.enable = function(renderable, enabled)
+    return "openspace.setPropertyValue('" .. renderable .. ".renderable.enabled', " .. (enabled and "true" or "false") .. ");";
+end
+
+-- Function that returns a lua table specifying a reversible ScheduledScript for 
+-- setting the enabled property of <renderable> to <enabled> at time <time>.
+helper.scheduledScript.enable = function(time, renderable, enabled)
+    return 
+    {
+        Time = time,
+        ReversibleLuaScript = {
+            Forward = helper.renderable.enable(renderable, enabled),
+            Backward = helper.renderable.enable(renderable, not enabled)
+        }
+    }
+end
+