Refactor and clean up lots of code.

init/helicopter.ks

@@ -0,0 +1,43 @@
+// assumptions about helicopter builds:
+// * AG10 toggles the rotor engine power. (with appropriate RPM set by default)
+// * AG9 is unmapped.
+// * Main throttle controls collective.
+
+runoncepath("lib/stabilize_helicopter").
+
+global done is false.
+on AG9 {
+  set done to true.
+  return true.
+}
+
+clearguis().
+
+// Main UI.
+local interface is gui(250, 300).
+set interface:X to 200.
+set interface:Y to 700.
+
+// Main menu elements in here.
+local y is interface:AddVLayout().
+local x is y:AddHLayout().
+
+set x:AddButton("HOVER"):onClick to {
+  PointStabilizeH().
+}.
+
+set x:AddButton("LAND"):onClick to {
+  // todo: consider a more elaborate landing script that adjusts
+  // velocity as a function of altitude.
+  when SHIP:STATUS = "LANDED" then {
+    set done to true.
+    set SHIP:CONTROL:PILOTMAINTHROTTLE to 0.5.
+    toggle AG10.
+    BRAKES on.
+  }
+  PointStabilizeH(-5).
+}.
+
+interface:show().
+
+wait until false.