Add sensor button, fix sensor code.

lib/navigation.ks

@@ -45,3 +45,22 @@ function CreateCircularizationNode {
 
   return n.
 }
+
+// function PredictGeo {
+//   parameter t.
+
+//   local pos is PositionAt(SHIP,t).
+//   local rDir is VDOT(SHIP:BODY:NORTH:FOREVECTOR,SHIP:BODY:ANGULARVEL). //the number of radians the body will rotate in one second (negative if rotating counter clockwise when viewed looking down on north
+//   local dT is t - TIME:SECONDS.
+//   local geoPos is SHIP:BODY:GeoPositionOf(pos).
+//   local drift is rDir * dT * CONSTANT:RADTODEG.
+//   local long is Mod(geoPos:LNG + drift, 360).
+//   if long < -180 {
+//     set long to long + 360.
+//   }
+//   if long > 180 {
+//     set long TO long - 360.
+//   }
+
+//   return LatLng(geoPos:LAT, long).
+// }

lib/sensors.ks

@@ -24,5 +24,31 @@ function ReadSensor {
   if not sList:HasKey(s) {
     return -1. // TODO: is -1 an impossible result for all sensors? I suspect not...
   }
-  return s:DISPLAY:TOSCALAR.
+
+  if not sList[s]:ACTIVE {
+    sList[s]:Toggle().
+  }
+
+  // UGH, this appears to be the only way to do this.
+  local ret is -1.
+  if s = "PRES" {
+    set ret to SHIP:SENSORS:PRES.
+  }
+  if s = "TEMP" {
+    set ret to SHIP:SENSORS:TEMP.
+  }
+  if s = "ACC" {
+    set ret to SHIP:SENSORS:ACC:MAG.
+  }
+  if s = "GRAV" {
+    set ret to SHIP:SENSORS:GRAV.
+  }
+  if s = "LIGHT" {
+    set ret to SHIP:SENSORS:LIGHT.
+  }
+
+  // turn off the sensor when we're done with it
+  sList[s]:Toggle().
+
+  return ret.
 }

lib/stabilize_rocket.ks

@@ -46,7 +46,7 @@ function Hover {
 function alignForHover {
   if ReadSensor("PRES") = 0 {
     // if we're in a vacuum, align with retrograde for smoother horizontal control.
-    lock STEERING to SHIP:SRFRETROGRADE.
+    lock STEERING to LookDirUp(SHIP:SRFRETROGRADE:FOREVECTOR, SHIP:FACING:TOPVECTOR)..
     print "Aligning with retrograde.".
     wait until done or VAng(SHIP:FACING:FOREVECTOR, SHIP:SRFRETROGRADE:FOREVECTOR) < 0.1.
     if done {
@@ -55,7 +55,7 @@ function alignForHover {
     }
   } else {
     // ... otherwise just align vertically.
-    lock STEERING to SHIP:UP.
+    lock STEERING to LookDirUp(SHIP:UP:FOREVECTOR, SHIP:FACING:TOPVECTOR)..
     print "Aligning vertical.".
     wait until done or VAng(SHIP:FACING:FOREVECTOR, SHIP:UP:FOREVECTOR) < 1.
     if done {