Merge libnode with libnavigation.

boot/rocket.ks

@@ -5,7 +5,6 @@ parameter debug is false.
 local compiled is list(
   "/lib/launch_rocket",
   "/lib/navigation",
-  "/lib/node",
   "/lib/stabilize_rocket",
   "/lib/ui",
   "/lib/throttle"

boot/satellite.ks

@@ -4,13 +4,12 @@ parameter debug is false.
 
 local compiled is list(
   "/lib/navigation",
-  "/lib/node",
   "/lib/throttle",
+  "/lib/ui",
   "/prog/nodestats"
 ).
 
 local copied is list(
-  "/lib/ui",
   "/prog/execnode",
   "/prog/circ",
   "/prog/satdeploy"

lib/navigation.ks

@@ -1,7 +1,5 @@
 // functions for calculating steering values.
 
-runoncepath("/lib/node").
-
 function GetPitch {
   parameter v is SHIP:FACING:FOREVECTOR.
   return 90 - vectorangle(SHIP:UP:FOREVECTOR, v).
@@ -61,27 +59,177 @@ function StoppingDistance {
   return dV*BurnTime(dV)/2.
 }
 
-// Figure out our closest approach to our current target within the next
-// N seconds. (default orbital_period * 2)
-// This is a horrible, terrible, no good, very bad brute force hack.
-// function timeAtClosestApproach {
-//   parameter maxSeconds is SHIP:ORBIT:PERIOD * 2.
+function ExecNode {
+  if not HASNODE {
+    print "No node to execute.".
+    return.
+  }
 
-//   // find the closest approach to pos
-//   local t is TIME.
-//   local minD is (PositionAt(TARGET, t) - PositionAt(SHIP, t)):MAG.
-//   local minT is t.
-//   until false {
-//     local d is (PositionAt(TARGET, t) - PositionAt(SHIP, t)):MAG.
-//     if d < minD {
-//       set minD to d.
-//       set minT to t.
-//     }
-//     set t to t+1.
-//   }
+  SAS off.
 
-//   return minT.
-// }
+  // begin the burn at leadT seconds before the node.
+  local leadT is BurnTime(NEXTNODE:DELTAV:MAG / 2).
+  local t is BurnTime(NEXTNODE:DELTAV:MAG).
+
+  if WillStage(NEXTNODE:DELTAV:MAG) {
+    print "WARNING: kOS will stage during this node execution. Safe cancellation requires reboot.".
+    when FlameOut() then {
+      print "Flameout detected. Staging.".
+      stage.
+    }
+  }
+  
+  print "Adjusting heading".
+  // The vector constant here should always align our "sides" with the universal up/down axis, so we can predictably place solar panels.
+  lock STEERING to LookDirUp(NEXTNODE:DELTAV, V(0,0,90)).
+  wait until VAng(SHIP:FACING:FOREVECTOR, STEERINGMANAGER:TARGET:FOREVECTOR) <= 0.1.
+
+  print "Warping to node.".
+  KUNIVERSE:TIMEWARP:WarpTo(NEXTNODE:TIME - leadT - 2).
+  wait until SHIP:UNPACKED.
+  wait until NEXTNODE:ETA <= leadT.
+
+  print "Executing burn.".
+  local dvMin is NEXTNODE:DELTAV:MAG.
+  lock THROTTLE to 1.0.
+  wait t.
+  lock THROTTLE to 0.0.
+
+  unlock THROTTLE.
+  unlock STEERING.
+  SAS on.
+  print "Node execution complete.".
+}
+
+// currently only works for testing against *current* stage.
+function WillStage {
+  parameter dV.
+  if not HASNODE { return false. }
+  return dV > SHIP:StageDeltaV(SHIP:STAGENUM):VACUUM.
+}
+
+// Calculate the time required to burn a given dV.
+// Assumes a perfectly spherical Kerbal in a vacuum.
+function BurnTime {
+  parameter totaldV, s is STAGE:NUMBER.
+  local totalT is 0.0.
+
+  local lastStage is false.
+  // We allow a small tolerance to deal with potential floating point errors.
+  until totaldV <= 0.001 {
+    local F is stageThrust(s).
+    local Isp is stageISP(s).
+    local m is stageMass(s).
+    // TODO: handle node execution in atmosphere?
+    local dV is min(totaldV, SHIP:StageDeltaV(s):VACUUM).
+    local t is calcBurnTime(dV, m, Isp, F).
+
+    set totaldV to totaldV - dV.
+    set s to s - 1.
+    set totalT to totalT + t.
+  }
+
+  return totalT.
+}
+
+// Convenience function to wrap the actual calculation for burn time.
+function calcBurnTime {
+  parameter dV, m, Isp, F.
+
+  if F = 0 or Isp = 0 {
+    print "WARNING: Tried to calculate burn time with a denominator value of 0. Returning 0. Your calculations are probably wrong.".
+    print "F: " + F .
+    print "Isp: " + Isp.
+    return 0.
+  }
+
+  local g0 is CONSTANT:G0.
+  return g0 * m * Isp * (1 - CONSTANT():E^(-dV/(g0*Isp))) / F.
+}
+
+// Calculate the ISP for a given stage.
+// Defaults to current stage. Assumes your ship is designed so that
+// engines are discarded immediately when they flame out.
+function stageISP {
+  parameter s is STAGE:NUMBER.
+
+  local en is list().
+  list ENGINES in en.
+
+  local ispSum is 0.
+  local eCount is 0.
+  for e in en {
+    if e:STAGE >= s and e:DECOUPLEDIN < s {
+      set ispSum to ispSum + e:VACUUMISP.
+      set eCount to eCount + 1.
+    }
+  }
+  if eCount = 0 { return 0. }
+  
+  return ispSum / eCount.
+}
+
+// Calculates the total thrust for the given stage, in kN.
+// Defaults to current stage. Assumes your ship is designed so that
+// engines are discarded immediately when they flame out.
+function stageThrust {
+  parameter s is STAGE:NUMBER.
+
+  local en is list().
+  list ENGINES in en.
+
+  local sum is 0.
+  for e in en {
+    if e:STAGE >= s and e:DECOUPLEDIN < s {
+      set sum to sum + e:POSSIBLETHRUST.
+    }
+  }
+
+  return sum.
+}
+
+// Determine mass at start of target stage.
+// This can handle Delta V-style launchers but
+// only if the central rocket remains in the stack
+// for exactly two stages, one of which is the current stage.
+// More complex staging with partially depleted tanks may produce
+// undefined behavior.
+function stageMass {
+  parameter s is STAGE:NUMBER.
+
+  local m is SHIP:MASS.
+  if s = SHIP:STAGENUM { return m. }
+
+  local ps is List().
+  list PARTS in ps.
+  for part in ps {
+    if part:DECOUPLEDIN >= s {
+      set m to m - part:MASS.
+    }
+  }
+
+  list ENGINES in ps.
+  for part in ps {
+    if part:DECOUPLEDIN < s and part:AVAILABLETHRUST > 0 {
+      set m to m - (part:MAXMASSFLOW * SHIP:StageDeltaV(SHIP:STAGENUM):DURATION).
+    }
+  }
+
+  return m.
+}
+
+// TODO: This would be better in throttle.ks or perhaps some sort of ship status library,
+// but we want to avoid too many inter-dependencies for now.
+function FlameOut {
+  local ens is List().
+  list engines in ens.
+  for en in ens {
+    if en:FLAMEOUT {
+      return true.
+    }
+  }
+  return false.
+}
 
 // function PredictGeo {
 //   parameter t.

prog/execnode.ks

@@ -1,4 +1,4 @@
 @lazyglobal off.
 
-runoncepath("/lib/node").
+runoncepath("/lib/navigation").
 ExecNode().

prog/nodestats.ks

@@ -1,6 +1,6 @@
 @lazyglobal off.
 
-runoncepath("/lib/node").
+runoncepath("/lib/navigation").
 
 if HASNODE {
   print "Node dV: " + NEXTNODE:DELTAV:MAG.

prog/rocket.ks

@@ -3,7 +3,6 @@
 runoncepath("/lib/ui").
 runoncepath("/lib/navigation").
 runoncepath("/lib/throttle").
-runoncepath("/lib/node").
 runoncepath("/lib/stabilize_rocket").
 runoncepath("/lib/launch_rocket").
 runoncepath("/lib/sensors").

prog/satdeploy.ks

@@ -11,7 +11,6 @@
 parameter name is "New Satellite".
 
 runoncepath("/lib/navigation").
-runoncepath("/lib/node").
 
 stage.