BulletSim: enablement and debugging of mesh terrain.

OpenSim/Region/Physics/BulletSPlugin/BSTerrainHeightmap.cs

@@ -44,10 +44,11 @@ public sealed class BSTerrainHeightmap : BSTerrainPhys
 {
     static string LogHeader = "[BULLETSIM TERRAIN HEIGHTMAP]";
 
-    BulletHeightMapInfo m_mapInfo;
+    BulletHeightMapInfo m_mapInfo = null;
 
-    public BSTerrainHeightmap(BSScene physicsScene, uint id, Vector3 regionSize)
+    // Constructor to build a default, flat heightmap terrain.
-        : base(physicsScene)
+    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);
@@ -60,21 +61,23 @@ public sealed class BSTerrainHeightmap : BSTerrainPhys
         m_mapInfo = new BulletHeightMapInfo(id, initialMap, IntPtr.Zero);
         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, uint id, float[] initialMap, 
+    public BSTerrainHeightmap(BSScene physicsScene, Vector3 regionBase, uint id, float[] initialMap, 
                                                     Vector3 minCoords, Vector3 maxCoords)
-        : base(physicsScene)
+        : base(physicsScene, regionBase, id)
     {
         m_mapInfo = new BulletHeightMapInfo(id, initialMap, IntPtr.Zero);
         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();
@@ -135,14 +138,12 @@ public sealed class BSTerrainHeightmap : BSTerrainPhys
         {
             if (m_mapInfo.terrainBody.ptr != IntPtr.Zero)
             {
-                if (BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr))
+                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;
     }
 
@@ -165,10 +166,5 @@ public sealed class BSTerrainHeightmap : BSTerrainPhys
         }
         return ret;
     }
-
-    public override Vector3 TerrainBase
-    {
-        get { return m_mapInfo.terrainRegionBase; }
-    }
 }
 }

OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs

@@ -45,14 +45,18 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 public abstract class BSTerrainPhys : IDisposable
 {
     public BSScene PhysicsScene { get; private set; }
+    // Base of the region in world coordinates. Coordinates inside the region are relative to this.
+    public Vector3 TerrainBase { get; private set; }
+    public uint ID { get; private set; }
 
-    public BSTerrainPhys(BSScene physicsScene)
+    public BSTerrainPhys(BSScene physicsScene, Vector3 regionBase, uint id)
     {
         PhysicsScene = physicsScene;
+        TerrainBase = regionBase;
+        ID = id;
     }
     public abstract void Dispose();
     public abstract float GetHeightAtXYZ(Vector3 pos);
-    public abstract Vector3 TerrainBase { get; }
 }
 
 // ==========================================================================================
@@ -133,7 +137,7 @@ public sealed class BSTerrainManager
                         (uint)CollisionFilterGroups.GroundPlaneFilter, (uint)CollisionFilterGroups.GroundPlaneMask);
 
         // Build an initial terrain and put it in the world. This quickly gets replaced by the real region terrain.
-        BSTerrainPhys initialTerrain = new BSTerrainHeightmap(PhysicsScene, BSScene.TERRAIN_ID, DefaultRegionSize);
+        BSTerrainPhys initialTerrain = new BSTerrainHeightmap(PhysicsScene, Vector3.Zero, BSScene.TERRAIN_ID, DefaultRegionSize);
         m_terrains.Add(Vector3.Zero, initialTerrain);
     }
 
@@ -208,10 +212,9 @@ public sealed class BSTerrainManager
                             BSScene.DetailLogZero, minCoords, maxCoords, inTaintTime);
 
         // Find high and low points of passed heightmap.
-        // The min and max passed in are usually the region objects can exist in (maximum
+        // The min and max passed in is usually the area objects can be in (maximum
         //     object height, for instance). The terrain wants the bounding box for the
         //     terrain so we replace passed min and max Z with the actual terrain min/max Z.
-        //      limit, for 
         float minZ = float.MaxValue;
         float maxZ = float.MinValue;
         foreach (float height in heightMap)
@@ -219,6 +222,11 @@ public sealed class BSTerrainManager
             if (height < minZ) minZ = height;
             if (height > maxZ) maxZ = height;
         }
+        if (minZ == maxZ)
+        {
+            // If min and max are the same, reduce min a little bit so a good bounding box is created.
+            minZ -= BSTerrainManager.HEIGHT_EQUAL_FUDGE;
+        }
         minCoords.Z = minZ;
         maxCoords.Z = maxZ;
 
@@ -240,7 +248,9 @@ public sealed class BSTerrainManager
 
                 if (MegaRegionParentPhysicsScene == null)
                 {
-                    BSTerrainPhys newTerrainPhys = new BSTerrainHeightmap(PhysicsScene, id,
+                    // BSTerrainPhys newTerrainPhys = new BSTerrainHeightmap(PhysicsScene, terrainRegionBase, id,
+                    //                                     heightMap, minCoords, maxCoords);
+                    BSTerrainPhys newTerrainPhys = new BSTerrainMesh(PhysicsScene, terrainRegionBase, id,
                                                         heightMap, minCoords, maxCoords);
                     m_terrains.Add(terrainRegionBase, newTerrainPhys);
 
@@ -282,8 +292,8 @@ public sealed class BSTerrainManager
             {
                 DetailLog("{0},UpdateTerrain:NewTerrain,taint,baseX={1},baseY={2}", 
                                             BSScene.DetailLogZero, minCoordsX.X, minCoordsX.Y);
-                BSTerrainPhys newTerrainPhys = new BSTerrainHeightmap(PhysicsScene, newTerrainID,
+                BSTerrainPhys newTerrainPhys = new BSTerrainHeightmap(PhysicsScene, terrainRegionBase, 
-                                                    heightMapX, minCoordsX, maxCoordsX);
+                                                newTerrainID, heightMapX, minCoordsX, maxCoordsX);
                 m_terrains.Add(terrainRegionBase, newTerrainPhys);
 
                 m_terrainModified = true;

OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs

@@ -44,30 +44,241 @@ public sealed class BSTerrainMesh : BSTerrainPhys
 {
     static string LogHeader = "[BULLETSIM TERRAIN MESH]";
 
-    public BSTerrainMesh(BSScene physicsScene, uint id, Vector3 regionSize) 
+    private float[] m_savedHeightMap;
-        : base(physicsScene)
+    int m_sizeX;
+    int m_sizeY;
+
+    BulletShape m_terrainShape;
+    BulletBody m_terrainBody;
+
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id, Vector3 regionSize) 
+        : base(physicsScene, regionBase, id)
     {
     }
 
-    public BSTerrainMesh(BSScene physicsScene /* parameters for making mesh */)
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id /* parameters for making mesh */)
-        : base(physicsScene)
+        : base(physicsScene, regionBase, id)
     {
     }
 
+    // Create terrain mesh from a heightmap.
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id, float[] initialMap, 
+                                                    Vector3 minCoords, Vector3 maxCoords)
+        : base(physicsScene, regionBase, id)
+    {
+        int indicesCount;
+        int[] indices;
+        int verticesCount;
+        float[] vertices;
+
+        m_savedHeightMap = initialMap;
+
+        m_sizeX = (int)(maxCoords.X - minCoords.X);
+        m_sizeY = (int)(maxCoords.Y - minCoords.Y);
+
+        if (!BSTerrainMesh.ConvertHeightmapToMesh(PhysicsScene, initialMap, m_sizeX, m_sizeY,
+                            (float)m_sizeX, (float)m_sizeY,
+                            Vector3.Zero, 1.0f,
+                            out indicesCount, out indices, out verticesCount, out vertices))
+        {
+            // DISASTER!!
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedConversionOfHeightmap", ID);
+            PhysicsScene.Logger.ErrorFormat("{0} Failed conversion of heightmap to mesh! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+        PhysicsScene.DetailLog("{0},BSTerrainMesh.create,afterConvertHeightmapToMesh,ver={1},ind={2}", 
+                                        ID, verticesCount, indicesCount);
+
+        m_terrainShape = new BulletShape(BulletSimAPI.CreateMeshShape2(PhysicsScene.World.ptr,
+                                        indicesCount, indices, verticesCount, vertices),
+                                        PhysicsShapeType.SHAPE_MESH);
+        if (m_terrainShape.ptr == IntPtr.Zero)
+        {
+            // DISASTER!!
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedCreationOfShape", ID);
+            physicsScene.Logger.ErrorFormat("{0} Failed creation of terrain mesh! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+        PhysicsScene.DetailLog("{0},BSTerrainMesh.create,afterCreateShape,shape={1}", ID, m_terrainShape);
+
+        // The terrain object initial position is at the center of the object
+        Vector3 centerPos;
+        centerPos.X = minCoords.X + (m_sizeX / 2f);
+        centerPos.Y = minCoords.Y + (m_sizeY / 2f);
+        centerPos.Z = minCoords.Z + ((maxCoords.Z - minCoords.Z) / 2f);
+        Quaternion rot = Quaternion.Identity;
+
+        PhysicsScene.DetailLog("{0},BSTerrainMesh.create,creatingBody,centerPos={1},rot={2}", ID, centerPos, rot);
+        m_terrainBody = new BulletBody(id, BulletSimAPI.CreateBodyWithDefaultMotionState2(
+                                                        m_terrainShape.ptr, ID, centerPos, rot));
+        if (m_terrainBody.ptr == IntPtr.Zero)
+        {
+            // DISASTER!!
+            physicsScene.Logger.ErrorFormat("{0} Failed creation of terrain body! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+        PhysicsScene.DetailLog("{0},BSTerrainMesh.create,afterCreateBody,body={1}", ID, m_terrainBody);
+
+        // Set current terrain attributes
+        BulletSimAPI.SetFriction2(m_terrainBody.ptr, PhysicsScene.Params.terrainFriction);
+        BulletSimAPI.SetHitFraction2(m_terrainBody.ptr, PhysicsScene.Params.terrainHitFraction);
+        BulletSimAPI.SetRestitution2(m_terrainBody.ptr, PhysicsScene.Params.terrainRestitution);
+        BulletSimAPI.SetCollisionFlags2(m_terrainBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
+
+        // Static objects are not very massive.
+        BulletSimAPI.SetMassProps2(m_terrainBody.ptr, 0f, Vector3.Zero);
+
+        // Return the new terrain to the world of physical objects
+        BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+
+        // redo its bounding box now that it is in the world
+        BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+
+        BulletSimAPI.SetCollisionFilterMask2(m_terrainBody.ptr,
+                            (uint)CollisionFilterGroups.TerrainFilter,
+                            (uint)CollisionFilterGroups.TerrainMask);
+
+        // Make it so the terrain will not move or be considered for movement.
+        BulletSimAPI.ForceActivationState2(m_terrainBody.ptr, ActivationState.DISABLE_SIMULATION);
+    }
+
     public override void Dispose()
     {
-        return;
+        if (m_terrainBody.ptr != IntPtr.Zero)
+        {
+            BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+            // Frees both the body and the shape.
+            BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+        }
     }
 
     public override float GetHeightAtXYZ(Vector3 pos)
     {
-        return 12345f;
+        // For the moment use the saved heightmap to get the terrain height.
-    }
+        // TODO: raycast downward to find the true terrain below the position.
+        float ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
 
-    public override Vector3 TerrainBase
+        int mapIndex = (int)pos.Y * m_sizeY + (int)pos.X;
+        try
         {
-        get { return Vector3.Zero; }
+            ret = m_savedHeightMap[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, TerrainBase, pos);
+            ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+        }
+        return ret;
     }
 
+    // Convert the passed heightmap to mesh information suitable for CreateMeshShape2().
+    // Return 'true' if successfully created.
+    public static bool ConvertHeightmapToMesh(
+                                BSScene physicsScene,
+                                float[] heightMap, int sizeX, int sizeY,    // parameters of incoming heightmap
+                                float extentX, float extentY,               // zero based range for output vertices
+                                Vector3 extentBase,                         // base to be added to all vertices
+                                float magnification,                        // number of vertices to create between heightMap coords
+                                out int indicesCountO, out int[] indicesO,
+                                out int verticesCountO, out float[] verticesO)
+    {
+        bool ret = false;
+
+        int indicesCount = 0;
+        int verticesCount = 0;
+        int[] indices = new int[0];
+        float[] vertices = new float[0];
+
+        // Simple mesh creation which assumes magnification == 1, sizeX == extentX and sizeY == extentY.
+        // TODO: do a more general solution that scales, adds new vertices and smoothes the result.
+
+        try
+        {
+            // One vertice per heightmap value plus the vertices off the top and bottom edge.
+            int totalVertices = (sizeX + 1) * (sizeY + 1);
+            vertices = new float[totalVertices * 3];
+            int totalIndices = sizeX * sizeY * 6;
+            indices = new int[totalIndices];
+
+            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,totVert={1},totInd={2}",
+                                    BSScene.DetailLogZero, totalVertices, totalIndices);
+            float magX = (float)sizeX / extentX;
+            float magY = (float)sizeY / extentY;
+            // Note that sizeX+1 vertices are created since there is land between this and the next region.
+            for (int yy = 0; yy <= sizeY; yy++)
+            {
+                for (int xx = 0; xx <= sizeX; xx++)     // Hint: the "<=" means we got through sizeX + 1 times
+                {
+                    int offset = yy * sizeX + xx;
+                    // Extend the height from the height from the last row or column
+                    if (yy == sizeY) offset -= sizeX;
+                    if (xx == sizeX) offset -= 1;
+                    float height = heightMap[offset];
+                    vertices[verticesCount + 0] = (float)xx * magX + extentBase.X;
+                    vertices[verticesCount + 1] = (float)yy * magY + extentBase.Y;
+                    vertices[verticesCount + 2] = height + extentBase.Z;
+                    if (physicsScene.PhysicsLogging.Enabled && verticesCount < 900)    // DEBUG DEBUG DEBUG
+                    {
+                        Vector3 genVertex = new Vector3(
+                                            vertices[verticesCount + 0],
+                                            vertices[verticesCount + 1],
+                                            vertices[verticesCount + 2]);
+                        physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,ii={1},vertex={2}", 
+                                                BSScene.DetailLogZero, verticesCount/3, genVertex);
+                    }
+                    verticesCount += 3;
+                }
+            }
+            verticesCount = verticesCount / 3;
+            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,completeVerts,verCount={1}", 
+                                            BSScene.DetailLogZero, verticesCount);
+
+            for (int yy = 0; yy < sizeY; yy++)
+            {
+                for (int xx = 0; xx < sizeX; xx++)
+                {
+                    int offset = yy * sizeX + xx;
+                    // Each vertices is presumed to be the upper left corner of a box of two triangles
+                    indices[indicesCount + 0] = offset;
+                    indices[indicesCount + 1] = offset + 1;
+                    indices[indicesCount + 2] = offset + sizeX + 1; // accounting for the extra column
+                    indices[indicesCount + 3] = offset + 1;
+                    indices[indicesCount + 4] = offset + sizeX + 2;
+                    indices[indicesCount + 5] = offset + sizeX + 1;
+                    if (indicesCount < (300 * 6))   // DEBUG DEBUG DEBUG
+                        physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,i0={1},i1={2},i2={3},i3={4},i4={5},i5={6}",   // DEEBUG DEBUG DEBUG
+                                                    BSScene.DetailLogZero, 
+                                                    indices[indicesCount + 0],
+                                                    indices[indicesCount + 1],
+                                                    indices[indicesCount + 2],
+                                                    indices[indicesCount + 3],
+                                                    indices[indicesCount + 4],
+                                                    indices[indicesCount + 5]
+                        );
+                    indicesCount += 6;
+                }
+            }
+            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,completeIndices,indCount={1}",   // DEEBUG DEBUG DEBUG
+                                                        LogHeader, indicesCount);                        // DEBUG
+            ret = true;
+        }
+        catch (Exception e)
+        {
+            physicsScene.Logger.ErrorFormat("{0} Failed conversion of heightmap to mesh. Base={1}, e={2}",
+                                                LogHeader, extentBase, e);
+        }
+
+        indicesCountO = indicesCount;
+        indicesO = indices;
+        verticesCountO = verticesCount;
+        verticesO = vertices;
+
+        return ret;
+    }
 }
 }

OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs

@@ -391,13 +391,13 @@ public enum CollisionFilterGroups : uint
     ObjectFilter            = BSolidFilter,
     ObjectMask              = BAllFilter,
     StaticObjectFilter      = BStaticFilter,
-    StaticObjectMask        = BAllFilter,
+    StaticObjectMask        = BAllFilter & ~BStaticFilter,   // static objects don't collide with each other
     LinksetFilter           = BLinksetFilter,
-    LinksetMask             = BAllFilter & ~BLinksetFilter,
+    LinksetMask             = BAllFilter & ~BLinksetFilter, // linkset objects don't collide with each other
     VolumeDetectFilter      = BSensorTrigger,
     VolumeDetectMask        = ~BSensorTrigger,
     TerrainFilter           = BTerrainFilter,
-    TerrainMask             = BAllFilter & ~BStaticFilter,
+    TerrainMask             = BAllFilter & ~BStaticFilter,  // static objects on the ground don't collide
     GroundPlaneFilter       = BGroundPlaneFilter,
     GroundPlaneMask         = BAllFilter