- added code to avoid vessel disintegration when deploying balloon at high velocity and also when the physics origin is teleported (happens every 6km, seems like a KSP system to avoid imprecision with big floating point numbers)

- added script to automatically build the zip package in release mode

.gitignore

@@ -2,3 +2,4 @@
 /Plugin/*.user
 /Plugin/obj
 /Plugin/bin
+/Aerostats.zip

Parts/HeliumBalloon/heliumBalloon.cfg

@@ -1,6 +1,6 @@
 PART
 {
-	name = balloon
+	name = heliumBalloon
 	module = Part
 	author = Youen
 	mesh = model.mu

Plugin/Aerostats.csproj

@@ -52,6 +52,9 @@
     <Compile Include="Util.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+  <PropertyGroup>
+    <PostBuildEvent>if $(ConfigurationName)==Release ("$(ProjectDir)..\build\build-package.bat")</PostBuildEvent>
+  </PropertyGroup>
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">

Plugin/ModuleAerostat.cs

@@ -82,6 +82,8 @@ namespace Aerostats
 
         private bool Staged;
 
+        private bool Destroyed;
+
         /// <summary>
         /// Gas quantity currently inside the balloon
         /// </summary>
@@ -96,6 +98,8 @@ namespace Aerostats
         private GameObject Balloon;
         private LineRenderer Spring;
 
+        private Vector3 EstimatedNextFramePosition;
+
         public override void OnStart(PartModule.StartState state)
         {
             if (!HighLogic.LoadedSceneIsEditor && !HighLogic.LoadedSceneIsFlight) { return; }
@@ -113,6 +117,7 @@ namespace Aerostats
             Balloon.transform.position = part.Rigidbody.position + part.Rigidbody.transform.up;
             Balloon.AddComponent<Rigidbody>();
             Balloon.rigidbody.mass = BalloonEmptyMass;
+            Balloon.rigidbody.velocity = part.rigidbody.velocity; // start with the same velocity or everything explodes when deploying from a moving vessel
 
             Balloon.rigidbody.angularDrag = 10.0f;
 
@@ -126,6 +131,8 @@ namespace Aerostats
             Spring.SetVertexCount(2);
 
             part.OnJustAboutToBeDestroyed += OnPartDestroyed;
+
+            EstimatedNextFramePosition = part.Rigidbody.position;
         }
 
         private void OnPartDestroyed()
@@ -134,10 +141,14 @@ namespace Aerostats
             Balloon = null;
             Spring = null;
             part.OnJustAboutToBeDestroyed -= OnPartDestroyed;
+            Destroyed = true;
         }
 
         private void FixedUpdate()
         {
+            if (Destroyed)
+                return;
+
             if (!Staged && GameSettings.LAUNCH_STAGES.GetKeyDown() && vessel.isActiveVessel && (part.inverseStage == Staging.CurrentStage - 1 || Staging.CurrentStage == 0))
             {
                 Staged = true;
@@ -146,6 +157,16 @@ namespace Aerostats
 
             if (Staged)
             {
+                // detect Krakensbane teleportation, and fix up the balloon position (otherwise it results in instant ship disintegration due to extreme forces on the spring)
+                if((part.Rigidbody.position - EstimatedNextFramePosition).magnitude > 1000.0f)
+                {
+                    ScreenMessages.PostScreenMessage("Krakensbane teleportation detected! (dist=" + (part.Rigidbody.position - EstimatedNextFramePosition).magnitude+")");
+                    var offset = part.rigidbody.position - EstimatedNextFramePosition;
+                    Balloon.rigidbody.position += offset;
+                    Balloon.transform.position = Balloon.rigidbody.position;
+                }
+                EstimatedNextFramePosition = part.rigidbody.position + part.rigidbody.velocity * Time.fixedDeltaTime;
+
                 float externalTemperature = (float)FlightGlobals.getExternalTemperature();
                 float balloonInternalTemperature = externalTemperature;
                 float externalPressure = Math.Max((float)FlightGlobals.getStaticPressure() * 1000.0f, 0.00001f);
@@ -214,7 +235,7 @@ namespace Aerostats
                 if(springLength > restLength)
                 {
                     float tensingLength = springLength - restLength;
-                    springForceMag = tensingLength * SpringHardness;
+                    springForceMag = Math.Min(tensingLength * SpringHardness, 500000.0f);
                     var springForce = springVec * (springForceMag / springLength * 0.001f);
                     part.rigidbody.AddForce(springForce, ForceMode.Force);
                     Balloon.rigidbody.AddForceAtPosition(-springForce, balloonAttachPoint, ForceMode.Force);

build/7z-License.txt

@@ -0,0 +1,56 @@
+  7-Zip
+  ~~~~~
+  License for use and distribution
+  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+  7-Zip Copyright (C) 1999-2010 Igor Pavlov.
+
+  Licenses for files are:
+
+    1) 7z.dll: GNU LGPL + unRAR restriction
+    2) All other files:  GNU LGPL
+
+  The GNU LGPL + unRAR restriction means that you must follow both 
+  GNU LGPL rules and unRAR restriction rules.
+
+
+  Note: 
+    You can use 7-Zip on any computer, including a computer in a commercial 
+    organization. You don't need to register or pay for 7-Zip.
+
+
+  GNU LGPL information
+  --------------------
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You can receive a copy of the GNU Lesser General Public License from 
+    http://www.gnu.org/
+
+
+  unRAR restriction
+  -----------------
+
+    The decompression engine for RAR archives was developed using source 
+    code of unRAR program.
+    All copyrights to original unRAR code are owned by Alexander Roshal.
+
+    The license for original unRAR code has the following restriction:
+
+      The unRAR sources cannot be used to re-create the RAR compression algorithm, 
+      which is proprietary. Distribution of modified unRAR sources in separate form 
+      or as a part of other software is permitted, provided that it is clearly
+      stated in the documentation and source comments that the code may
+      not be used to develop a RAR (WinRAR) compatible archiver.
+
+
+  --
+  Igor Pavlov

build/build-package.bat

@@ -0,0 +1,47 @@
+@echo off
+
+rem make sure the initial working directory is the one containing the current script
+SET scriptPath=%~dp0
+SET initialWD=%CD%
+cd %scriptPath%
+
+cd ..
+
+rd /s /q package
+mkdir package
+cd package
+mkdir GameData
+cd GameData
+
+mkdir Aerostats
+cd Aerostats
+xcopy /y ..\..\..\License.txt .
+xcopy /y ..\..\..\resources.cfg .
+xcopy /y ..\..\..\TweakScale.cfg .
+
+mkdir Plugin
+xcopy /y ..\..\..\Plugin\bin\Release\Aerostats.dll Plugin
+
+mkdir Parts
+cd Parts
+
+mkdir HeliumBalloon
+xcopy /y ..\..\..\..\Parts\HeliumBalloon\heliumBalloon.cfg HeliumBalloon
+xcopy /y ..\..\..\..\Parts\HeliumBalloon\model.mu HeliumBalloon
+xcopy /y ..\..\..\..\Parts\HeliumBalloon\model000.dds HeliumBalloon
+xcopy /y ..\..\..\..\Parts\HeliumBalloon\model001.dds HeliumBalloon
+
+mkdir HeliumTankRadial
+xcopy /y ..\..\..\..\Parts\HeliumTankRadial\heliumTankRadial.cfg HeliumTankRadial
+xcopy /y ..\..\..\..\Parts\HeliumTankRadial\model.mu HeliumTankRadial
+xcopy /y ..\..\..\..\Parts\HeliumTankRadial\ksp_r_xenonTank_diff.dds HeliumTankRadial
+
+cd "%scriptPath%..\package"
+IF EXIST ..\Aerostats.zip del ..\Aerostats.zip
+"%scriptPath%7z.exe" a ..\Aerostats.zip GameData
+cd "%scriptPath%.."
+rd /s /q package
+
+cd %initialWD%
+
+pause