* Initial commit of BulletSimN (BulletSNPlugin). Purely C# implementation of BulletSim. This is designed to be /as close as possible/ to the BulletSim plugin while still being entirely in the managed space to make keeping it up to date easy as possible (no thinking work). This implementation is /slower/ then the c++ version just because it's fully managed, so it's not appropriate for huge sims, but it will run small ones OK. At the moment, it supports all known features of BulletSim. Think of it like.. POS but everything works. To use this plugin, set the physics plugin to BulletSimN.

1 files changed, 175 insertions, 0 deletions

diff --git a/OpenSim/Region/Physics/BulletSNPlugin/BSTerrainHeightmap.cs b/OpenSim/Region/Physics/BulletSNPlugin/BSTerrainHeightmap.cs
new file mode 100644
index 0000000..252953b
--- /dev/null
+++ b/OpenSim/Region/Physics/BulletSNPlugin/BSTerrainHeightmap.cs
@@ -0,0 +1,175 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyrightD
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+using OpenSim.Framework;
+using OpenSim.Region.Framework;
+using OpenSim.Region.CoreModules;
+using OpenSim.Region.Physics.Manager;
+
+using Nini.Config;
+using log4net;
+
+using OpenMetaverse;
+
+namespace OpenSim.Region.Physics.BulletSNPlugin
+{
+public sealed class BSTerrainHeightmap : BSTerrainPhys
+{
+    static string LogHeader = "[BULLETSIM TERRAIN HEIGHTMAP]";
+
+    BulletHeightMapInfo m_mapInfo = null;
+
+    // Constructor to build a default, flat heightmap terrain.
+    public BSTerrainHeightmap(BSScene physicsScene, Vector3 regionBase, uint id, Vector3 regionSize)
+        : base(physicsScene, regionBase, id)
+    {
+        Vector3 minTerrainCoords = new Vector3(0f, 0f, BSTerrainManager.HEIGHT_INITIALIZATION - BSTerrainManager.HEIGHT_EQUAL_FUDGE);
+        Vector3 maxTerrainCoords = new Vector3(regionSize.X, regionSize.Y, BSTerrainManager.HEIGHT_INITIALIZATION);
+        int totalHeights = (int)maxTerrainCoords.X * (int)maxTerrainCoords.Y;
+        float[] initialMap = new float[totalHeights];
+        for (int ii = 0; ii < totalHeights; ii++)
+        {
+            initialMap[ii] = BSTerrainManager.HEIGHT_INITIALIZATION;
+        }
+        m_mapInfo = new BulletHeightMapInfo(id, initialMap, null);
+        m_mapInfo.minCoords = minTerrainCoords;
+        m_mapInfo.maxCoords = maxTerrainCoords;
+        m_mapInfo.terrainRegionBase = TerrainBase;
+        // Don't have to free any previous since we just got here.
+        BuildHeightmapTerrain();
+    }
+
+    // This minCoords and maxCoords passed in give the size of the terrain (min and max Z
+    //         are the high and low points of the heightmap).
+    public BSTerrainHeightmap(BSScene physicsScene, Vector3 regionBase, uint id, float[] initialMap, 
+                                                    Vector3 minCoords, Vector3 maxCoords)
+        : base(physicsScene, regionBase, id)
+    {
+        m_mapInfo = new BulletHeightMapInfo(id, initialMap, null);
+        m_mapInfo.minCoords = minCoords;
+        m_mapInfo.maxCoords = maxCoords;
+        m_mapInfo.minZ = minCoords.Z;
+        m_mapInfo.maxZ = maxCoords.Z;
+        m_mapInfo.terrainRegionBase = TerrainBase;
+
+        // Don't have to free any previous since we just got here.
+        BuildHeightmapTerrain();
+    }
+
+    public override void Dispose()
+    {
+        ReleaseHeightMapTerrain();
+    }
+
+    // Using the information in m_mapInfo, create the physical representation of the heightmap.
+    private void BuildHeightmapTerrain()
+    {
+        m_mapInfo.Ptr = BulletSimAPI.CreateHeightMapInfo2(PhysicsScene.World.ptr, m_mapInfo.ID,
+                                m_mapInfo.minCoords, m_mapInfo.maxCoords, 
+                                m_mapInfo.heightMap, BSParam.TerrainCollisionMargin);
+
+        // Create the terrain shape from the mapInfo
+        m_mapInfo.terrainShape = new BulletShape(BulletSimAPI.CreateTerrainShape2(m_mapInfo.Ptr),
+                                                    BSPhysicsShapeType.SHAPE_TERRAIN);
+
+        // The terrain object initial position is at the center of the object
+        Vector3 centerPos;
+        centerPos.X = m_mapInfo.minCoords.X + (m_mapInfo.sizeX / 2f);
+        centerPos.Y = m_mapInfo.minCoords.Y + (m_mapInfo.sizeY / 2f);
+        centerPos.Z = m_mapInfo.minZ + ((m_mapInfo.maxZ - m_mapInfo.minZ) / 2f + 0.5f);
+
+        m_mapInfo.terrainBody = new BulletBody(m_mapInfo.ID,
+                BulletSimAPI.CreateBodyWithDefaultMotionState2(m_mapInfo.terrainShape.ptr,
+                                            m_mapInfo.ID, centerPos, Quaternion.Identity));
+
+        // Set current terrain attributes
+        BulletSimAPI.SetFriction2(m_mapInfo.terrainBody.ptr, BSParam.TerrainFriction);
+        BulletSimAPI.SetHitFraction2(m_mapInfo.terrainBody.ptr, BSParam.TerrainHitFraction);
+        BulletSimAPI.SetRestitution2(m_mapInfo.terrainBody.ptr, BSParam.TerrainRestitution);
+        BulletSimAPI.SetCollisionFlags2(m_mapInfo.terrainBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
+
+        // Return the new terrain to the world of physical objects
+        BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr, centerPos, Quaternion.Identity);
+
+        // redo its bounding box now that it is in the world
+        BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr);
+
+        m_mapInfo.terrainBody.collisionType = CollisionType.Terrain;
+        m_mapInfo.terrainBody.ApplyCollisionMask();
+
+        // Make it so the terrain will not move or be considered for movement.
+        BulletSimAPI.ForceActivationState2(m_mapInfo.terrainBody.ptr, ActivationState.DISABLE_SIMULATION);
+
+        return;
+    }
+
+    // If there is information in m_mapInfo pointing to physical structures, release same.
+    private void ReleaseHeightMapTerrain()
+    {
+        if (m_mapInfo != null)
+        {
+            if (m_mapInfo.terrainBody.HasPhysicalBody)
+            {
+                BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr);
+                // Frees both the body and the shape.
+                BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr);
+                BulletSimAPI.ReleaseHeightMapInfo2(m_mapInfo.Ptr);
+            }
+        }
+        m_mapInfo = null;
+    }
+
+    // The passed position is relative to the base of the region.
+    public override float GetTerrainHeightAtXYZ(Vector3 pos)
+    {
+        float ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+
+        int mapIndex = (int)pos.Y * (int)m_mapInfo.sizeY + (int)pos.X;
+        try
+        {
+            ret = m_mapInfo.heightMap[mapIndex];
+        }
+        catch
+        {
+            // Sometimes they give us wonky values of X and Y. Give a warning and return something.
+            PhysicsScene.Logger.WarnFormat("{0} Bad request for terrain height. terrainBase={1}, pos={2}",
+                                LogHeader, m_mapInfo.terrainRegionBase, pos);
+            ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+        }
+        return ret;
+    }
+
+    // The passed position is relative to the base of the region.
+    public override float GetWaterLevelAtXYZ(Vector3 pos)
+    {
+        return PhysicsScene.SimpleWaterLevel;
+    }
+}
+}