From d21601d497e81108860e880653757dc3773cdb47 Mon Sep 17 00:00:00 2001
From: Dahlia Trimble <dahliatrimble@gmail.com>
Date: Thu, 12 Feb 2009 07:58:10 +0000
Subject: [PATCH] Thanks Kitto Flora for a patch that adds automatic min fly
 height to ODE - Mantis #3134

---
 CONTRIBUTORS.txt                               |  1 +
 .../Region/Physics/OdePlugin/ODECharacter.cs   | 12 +++++++++++-
 OpenSim/Region/Physics/OdePlugin/OdePlugin.cs  | 18 ++++++++++--------
 3 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index ea32241a57..e214720957 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -61,6 +61,7 @@ Patches
 * Kayne
 * Kevin Cozens
 * kinoc (Daxtron Labs)
+* Kitto Flora
 * krtaylor (IBM)
 * lulurun 
 * M.Igarashi
diff --git a/OpenSim/Region/Physics/OdePlugin/ODECharacter.cs b/OpenSim/Region/Physics/OdePlugin/ODECharacter.cs
index 2cdc988650..b2981fe8d8 100644
--- a/OpenSim/Region/Physics/OdePlugin/ODECharacter.cs
+++ b/OpenSim/Region/Physics/OdePlugin/ODECharacter.cs
@@ -832,8 +832,18 @@ namespace OpenSim.Region.Physics.OdePlugin
             if (flying)
             {
                 vec.Z += ((-1 * _parent_scene.gravityz)*m_mass);
-            }
 
+                //Added for auto fly height. Kitto Flora
+                d.Vector3 pos = d.BodyGetPosition(Body);
+                float ground_height = _parent_scene.GetTerrainHeightAtXY(pos.X, pos.Y);
+                float target_altitude = ground_height + 3.0f;    // This is  the min fly height
+                if(pos.Z < target_altitude)
+                {
+                    vec.Z += (target_altitude - pos.Z) * PID_P * 5.0f;
+                }
+                // end add Kitto Flora
+
+            }
 
             doForce(vec);
         }
diff --git a/OpenSim/Region/Physics/OdePlugin/OdePlugin.cs b/OpenSim/Region/Physics/OdePlugin/OdePlugin.cs
index d7d471f1d6..0f18be4ab8 100644
--- a/OpenSim/Region/Physics/OdePlugin/OdePlugin.cs
+++ b/OpenSim/Region/Physics/OdePlugin/OdePlugin.cs
@@ -1,3 +1,4 @@
+
 /*
  * Copyright (c) Contributors, http://opensimulator.org/
  * See CONTRIBUTORS.TXT for a full list of copyright holders.
@@ -205,7 +206,7 @@ namespace OpenSim.Region.Physics.OdePlugin
         private float[] _watermap;
         private bool m_filterCollisions = true;
 
-        // private float[] _origheightmap;
+        private float[] _origheightmap;    // Used for Fly height. Kitto Flora
 
         private d.NearCallback nearCallback;
         public d.TriCallback triCallback;
@@ -1284,12 +1285,13 @@ namespace OpenSim.Region.Physics.OdePlugin
         }
 
         #endregion
-
-// TODO: unused
-//         private float GetTerrainHeightAtXY(float x, float y)
-//         {
-//             return (float)_origheightmap[(int)y * Constants.RegionSize + (int)x];
-//         }
+       
+// Recovered for use by fly height. Kitto Flora
+        public float GetTerrainHeightAtXY(float x, float y)
+        {
+            return (float)_origheightmap[(int)y * Constants.RegionSize + (int)x];
+        }
+// End recovered. Kitto Flora
 
         public void addCollisionEventReporting(PhysicsActor obj)
         {
@@ -2958,7 +2960,7 @@ namespace OpenSim.Region.Physics.OdePlugin
         {
             // this._heightmap[i] = (double)heightMap[i];
             // dbm (danx0r) -- creating a buffer zone of one extra sample all around
-            // _origheightmap = heightMap;
+            _origheightmap = heightMap;    // Used for Fly height. Kitto Flora
             const uint heightmapWidth = m_regionWidth + 2;
             const uint heightmapHeight = m_regionHeight + 2;
             const uint heightmapWidthSamples = 2*m_regionWidth + 2;