mockingbirdnest · Mar 11, 2017 · Mar 11, 2017 · Mar 11, 2017 · Mar 11, 2017 · Mar 11, 2017
Showing with 70 additions and 71 deletions.

+12 −6 ksp_plugin/interface.cpp

+23 −32 ksp_plugin/plugin.cpp

+6 −7 ksp_plugin/plugin.hpp

+27 −26 ksp_plugin_adapter/ksp_plugin_adapter.cs

+2 −0 serialization/journal.proto
diff --git a/ksp_plugin/interface.cpp b/ksp_plugin/interface.cpp
@@ -217,10 +217,13 @@ WXYZ principia__CelestialSphereRotation(Plugin const* const plugin) {
 }
 
 QP principia__CelestialWorldDegreesOfFreedom(Plugin const* const plugin,
-                                             int const index) {
-  journal::Method<journal::CelestialWorldDegreesOfFreedom> m({plugin, index});
+                                             int const index,
+                                             PartId const part_at_origin) {
+  journal::Method<journal::CelestialWorldDegreesOfFreedom> m(
+      {plugin, index, part_at_origin});
   CHECK_NOTNULL(plugin);
-  auto const result = plugin->CelestialWorldDegreesOfFreedom(index);
+  auto const result =
+      plugin->CelestialWorldDegreesOfFreedom(index, part_at_origin);
   return m.Return(
       {ToXYZ((result.position() - World::origin).coordinates() / Metre),
        ToXYZ(result.velocity().coordinates() / (Metre / Second))});
@@ -351,10 +354,13 @@ int principia__GetBufferedLogging() {
 }
 
 QP principia__GetPartActualDegreesOfFreedom(Plugin const* const plugin,
-                                            PartId const part_id) {
-  journal::Method<journal::GetPartActualDegreesOfFreedom> m({plugin, part_id});
+                                            PartId const part_id,
+                                            PartId const part_at_origin) {
+  journal::Method<journal::GetPartActualDegreesOfFreedom> m(
+      {plugin, part_id, part_at_origin});
   DegreesOfFreedom<World> const degrees_of_freedom =
-      CHECK_NOTNULL(plugin)->GetPartActualDegreesOfFreedom(part_id);
+      CHECK_NOTNULL(plugin)->GetPartActualDegreesOfFreedom(part_id,
+                                                           part_at_origin);
   return m.Return(QP{
       ToXYZ((degrees_of_freedom.position() - World::origin).coordinates() /
             Metre),

diff --git a/ksp_plugin/plugin.cpp b/ksp_plugin/plugin.cpp
@@ -604,19 +604,8 @@ void Plugin::AdvanceTime(Instant const& t, Angle const& planetarium_rotation) {
     Vessel& vessel = *pair.second;
     vessel.AdvanceTime();
   }
-  if (loaded_vessels_.empty()) {
-    bubble_barycentre_ = std::experimental::nullopt;
-  } else {
-    BarycentreCalculator<DegreesOfFreedom<Barycentric>, Mass>
-        bubble_barycentre_calculator;
-    for (not_null<Vessel*> const vessel : loaded_vessels_) {
-      vessel->ForAllParts([&bubble_barycentre_calculator](Part& part) {
-        part.clear_intrinsic_force();
-        bubble_barycentre_calculator.Add(part.degrees_of_freedom(),
-                                         part.mass());
-      });
-    }
-    bubble_barycentre_ = bubble_barycentre_calculator.Get();
+  for (not_null<Vessel*> const vessel : loaded_vessels_) {
+    vessel->ForAllParts([](Part& part) { part.clear_intrinsic_force(); });
   }
 
   VLOG(1) << "Time has been advanced" << '\n'
@@ -628,34 +617,36 @@ void Plugin::AdvanceTime(Instant const& t, Angle const& planetarium_rotation) {
 }
 
 DegreesOfFreedom<World> Plugin::GetPartActualDegreesOfFreedom(
-    PartId const part_id) const {
-  CHECK(bubble_barycentre_);
+    PartId const part_id,
+    PartId const part_at_origin) const {
+  auto const world_origin = FindOrDie(part_id_to_vessel_, part_at_origin)->
+                                part(part_at_origin)->
+                                degrees_of_freedom();
   RigidMotion<Barycentric, World> barycentric_to_world{
       RigidTransformation<Barycentric, World>{
-          bubble_barycentre_->position(), World::origin, BarycentricToWorld()},
+          world_origin.position(), World::origin, BarycentricToWorld()},
       AngularVelocity<Barycentric>{},
-      bubble_barycentre_->velocity()};
-  return barycentric_to_world(FindOrDie(part_id_to_vessel_, part_id)
-                                  ->part(part_id)
-                                  ->degrees_of_freedom());
-}
-
-DegreesOfFreedom<Barycentric> Plugin::GetBubbleBarycentre() const {
-  CHECK(bubble_barycentre_);
-  return *bubble_barycentre_;
+      world_origin.velocity()};
+  return barycentric_to_world(FindOrDie(part_id_to_vessel_, part_id)->
+                                  part(part_id)->
+                                  degrees_of_freedom());
 }
 
 DegreesOfFreedom<World> Plugin::CelestialWorldDegreesOfFreedom(
-    Index const index) const {
+    Index const index,
+    PartId const part_at_origin) const {
+  auto const world_origin = FindOrDie(part_id_to_vessel_, part_at_origin)->
+                                part(part_at_origin)->
+                                degrees_of_freedom();
   RigidMotion<Barycentric, World> barycentric_to_world{
-      RigidTransformation<Barycentric, World>{GetBubbleBarycentre().position(),
-                                              World::origin,
-                                              BarycentricToWorld()},
+      RigidTransformation<Barycentric, World>{
+          world_origin.position(), World::origin, BarycentricToWorld()},
       AngularVelocity<Barycentric>{},
-      GetBubbleBarycentre().velocity()};
+      world_origin.velocity()};
   return barycentric_to_world(
-      FindOrDie(celestials_, index)->trajectory().EvaluateDegreesOfFreedom(
-          current_time_, /*hint=*/nullptr));
+      FindOrDie(celestials_, index)->
+          trajectory().EvaluateDegreesOfFreedom(current_time_,
+                                                /*hint=*/nullptr));
 }
 
 void Plugin::ForgetAllHistoriesBefore(Instant const& t) const {

diff --git a/ksp_plugin/plugin.hpp b/ksp_plugin/plugin.hpp
@@ -221,17 +221,17 @@ class Plugin {
   virtual void AdvanceTime(Instant const& t, Angle const& planetarium_rotation);
 
   // Returns the degrees of freedom of the given part in |World|, assuming that
-  // the origin of |World| is fixed at |bubble_barycentre_|.  The part must be
-  // in a loaded vessel.
+  // the origin of |World| is fixed at the centre of mass of the
+  // |part_at_origin|.
   virtual DegreesOfFreedom<World> GetPartActualDegreesOfFreedom(
-      PartId part_id) const;
-
-  virtual DegreesOfFreedom<Barycentric> GetBubbleBarycentre() const;
+      PartId part_id,
+      PartId part_at_origin) const;
 
   // Returns the |World| degrees of freedom of the |Celestial| with the given
   // |Index|, identifying the origin of |World| with that of |Bubble|.
   virtual DegreesOfFreedom<World> CelestialWorldDegreesOfFreedom(
-      Index const index) const;
+      Index const index,
+      PartId part_at_origin) const;
 
   // Forgets the histories of the |celestials_| and of the vessels before |t|.
   virtual void ForgetAllHistoriesBefore(Instant const& t) const;
@@ -511,7 +511,6 @@ class Plugin {
   // The vessels that were inserted unloaded and have yet to be collected into a
   // pile-up.
   std::set<not_null<Vessel*>> new_unloaded_vessels_;
-  std::experimental::optional<DegreesOfFreedom<Barycentric>> bubble_barycentre_;
 
   friend class NavballFrameField;
   friend class TestablePlugin;

diff --git a/ksp_plugin_adapter/ksp_plugin_adapter.cs b/ksp_plugin_adapter/ksp_plugin_adapter.cs
@@ -796,36 +796,37 @@ private System.Collections.IEnumerator
      // We don't want to do too many things here, since all the KSP classes
      // still think they're in the preceding step.  We only nudge the Unity
      // transforms of loaded vessels & their parts.
-     // TODO(egg): get vessel nudged positions and call Vessel.SetPosition.
-     // Hopefully that will be enough.
-     foreach (Vessel vessel in FlightGlobals.VesselsLoaded) {
-       // TODO(egg): if I understand anything, there should probably be a
-       // special treatment for loaded packed vessels.  I don't understand
-       // anything though.
-       if (vessel.packed || !plugin_.HasVessel(vessel.id.ToString())) {
-         continue;
-       }
-       foreach (Part part in vessel.parts) {
-         if (part.rb == null) {
+     if (has_active_vessel_in_space() && !FlightGlobals.ActiveVessel.packed) {
+       // TODO(egg): move this to the C++, this is just to check that I
+       // understand the issue.
+       foreach (Vessel vessel in FlightGlobals.VesselsLoaded) {
+         // TODO(egg): if I understand anything, there should probably be a
+         // special treatment for loaded packed vessels.  I don't understand
+         // anything though.
+         if (vessel.packed || !plugin_.HasVessel(vessel.id.ToString())) {
            continue;
          }
-         QP part_actual_degrees_of_freedom =
-             plugin_.GetPartActualDegreesOfFreedom(part.flightID);
-         // TODO(egg): use the centre of mass.  Here it's a bit tedious, some
-         // transform nonsense must probably be done.
-         Log.Error(
-             "q correction " +
-             ((Vector3d)part_actual_degrees_of_freedom.q - part.rb.position));
-         Log.Error(
-             "v correction " +
-             ((Vector3d)part_actual_degrees_of_freedom.p - part.rb.velocity));
-         part.rb.position = (Vector3d)part_actual_degrees_of_freedom.q;
-         part.rb.velocity = (Vector3d)part_actual_degrees_of_freedom.p;
+         foreach (Part part in vessel.parts) {
+           if (part.rb == null) {
+             continue;
+           }
+           QP part_actual_degrees_of_freedom =
+               plugin_.GetPartActualDegreesOfFreedom(part.flightID, FlightGlobals.ActiveVessel.rootPart.flightID);
+           // TODO(egg): use the centre of mass.  Here it's a bit tedious, some
+           // transform nonsense must probably be done.
+           Log.Error(
+               "q correction " +
+               ((Vector3d)part_actual_degrees_of_freedom.q - part.rb.position));
+           Log.Error(
+               "v correction " +
+               ((Vector3d)part_actual_degrees_of_freedom.p - part.rb.velocity));
+           part.rb.position = (Vector3d)part_actual_degrees_of_freedom.q;
+           part.rb.velocity = (Vector3d)part_actual_degrees_of_freedom.p;
+         }
        }
-     }
-     if (has_active_vessel_in_space() && !FlightGlobals.ActiveVessel.packed) {
        QP main_body_dof = plugin_.CelestialWorldDegreesOfFreedom(
-           FlightGlobals.ActiveVessel.mainBody.flightGlobalsIndex);
+           FlightGlobals.ActiveVessel.mainBody.flightGlobalsIndex,
+           FlightGlobals.ActiveVessel.rootPart.flightID);
        Log.Error("change in framevel: " +
                  (-(Vector3d)main_body_dof.p - krakensbane.FrameVel));
        krakensbane.FrameVel = -(Vector3d)main_body_dof.p;

diff --git a/serialization/journal.proto b/serialization/journal.proto
@@ -197,6 +197,7 @@ message CelestialWorldDegreesOfFreedom {
     required fixed64 plugin = 1 [(pointer_to) = "Plugin const",
                                  (is_subject) = true];
     required int32 index = 2;
+    required fixed32 part_at_origin = 3;
   }
   message Return {
     required QP result = 1;
@@ -606,6 +607,7 @@ message GetPartActualDegreesOfFreedom {
     required fixed64 plugin = 1 [(pointer_to) = "Plugin const",
                                  (is_subject) = true];
     required fixed32 part_id = 2;
+    required fixed32 part_at_origin = 3;
   }
   message Return {
     required QP result = 1;