From a3212ab37d7517785c91808cc0f8021d207005ed Mon Sep 17 00:00:00 2001
From: Mathew Sutcliffe <oktal3700@gmail.com>
Date: Sat, 14 Jan 2017 04:01:24 +0000
Subject: [PATCH] refs #852 To avoid sudden movements, don't bother trying to
 interpolate when we have less than two position updates.

---
 src/xbus/traffic.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/xbus/traffic.cpp b/src/xbus/traffic.cpp
index 2dd8ea87a..a2fe5507d 100644
--- a/src/xbus/traffic.cpp
+++ b/src/xbus/traffic.cpp
@@ -333,6 +333,8 @@ namespace XBus
         {
         case xpmpDataType_Position:
             {
+                if (plane->situations.size() < 3) { return xpmpData_Unavailable; } // avoid sudden movements when a pilot connects
+
                 BlackMisc::Simulation::IInterpolator::InterpolationStatus status;
                 const auto situation = m_interpolator->getInterpolatedSituation(plane->situations, -1, plane->hints(m_interpolator), status);
                 if (! status.didInterpolationSucceed()) { return xpmpData_Unavailable; }