1 files changed, 423 insertions, 0 deletions

diff --git a/OpenSim/Framework/TerrainData.cs b/OpenSim/Framework/TerrainData.cs
new file mode 100644
index 0000000..9325df2
--- /dev/null
+++ b/OpenSim/Framework/TerrainData.cs
@@ -0,0 +1,423 @@
+/*
+ * 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 copyright
+ *       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.IO;
+using System.Reflection;
+
+using OpenMetaverse;
+
+using log4net;
+
+namespace OpenSim.Framework
+{
+    public abstract class TerrainData
+    {
+        // Terrain always is a square
+        public int SizeX { get; protected set; }
+        public int SizeY { get; protected set; }
+        public int SizeZ { get; protected set; }
+
+        // A height used when the user doesn't specify anything
+        public const float DefaultTerrainHeight = 21f;
+
+        public abstract float this[int x, int y] { get; set; }
+        // Someday terrain will have caves
+        public abstract float this[int x, int y, int z] { get; set; }
+
+        public bool IsTainted { get; protected set; }
+        public abstract bool IsTaintedAt(int xx, int yy);
+        public abstract void ClearTaint();
+
+        public abstract void ClearLand();
+        public abstract void ClearLand(float height);
+
+        // Return a representation of this terrain for storing as a blob in the database.
+        // Returns 'true' to say blob was stored in the 'out' locations.
+        public abstract bool GetDatabaseBlob(out int DBFormatRevisionCode, out Array blob);
+
+        // Given a revision code and a blob from the database, create and return the right type of TerrainData.
+        // The sizes passed are the expected size of the region. The database info will be used to
+        //     initialize the heightmap of that sized region with as much data is in the blob.
+        // Return created TerrainData or 'null' if unsuccessful.
+        public static TerrainData CreateFromDatabaseBlobFactory(int pSizeX, int pSizeY, int pSizeZ, int pFormatCode, byte[] pBlob)
+        {
+            // For the moment, there is only one implementation class
+            return new HeightmapTerrainData(pSizeX, pSizeY, pSizeZ, pFormatCode, pBlob);
+        }
+
+        // return a special compressed representation of the heightmap in shorts
+        public abstract short[] GetCompressedMap();
+        public abstract float CompressionFactor { get; }
+
+        public abstract double[,] GetDoubles();
+        public abstract TerrainData Clone();
+    }
+
+    // The terrain is stored in the database as a blob with a 'revision' field.
+    // Some implementations of terrain storage would fill the revision field with
+    //    the time the terrain was stored. When real revisions were added and this
+    //    feature removed, that left some old entries with the time in the revision
+    //    field.
+    // Thus, if revision is greater than 'RevisionHigh' then terrain db entry is
+    //    left over and it is presumed to be 'Legacy256'.
+    // Numbers are arbitrary and are chosen to to reduce possible mis-interpretation.
+    // If a revision does not match any of these, it is assumed to be Legacy256.
+    public enum DBTerrainRevision
+    {
+        // Terrain is 'double[256,256]'
+        Legacy256 = 11,
+        // Terrain is 'int32, int32, float[,]' where the ints are X and Y dimensions
+        // The dimensions are presumed to be multiples of 16 and, more likely, multiples of 256.
+        Variable2D = 22,
+        // Terrain is 'int32, int32, int32, int16[]' where the ints are X and Y dimensions
+        //   and third int is the 'compression factor'. The heights are compressed as
+        //   "short compressedHeight = (short)(height * compressionFactor);"
+        // The dimensions are presumed to be multiples of 16 and, more likely, multiples of 256.
+        Compressed2D = 27,
+        // A revision that is not listed above or any revision greater than this value is 'Legacy256'.
+        RevisionHigh = 1234
+    }
+
+    // Version of terrain that is a heightmap.
+    // This should really be 'LLOptimizedHeightmapTerrainData' as it includes knowledge
+    //    of 'patches' which are 16x16 terrain areas which can be sent separately to the viewer.
+    // The heighmap is kept as an array of short integers. The integer values are converted to
+    //    and from floats by TerrainCompressionFactor. Shorts are used to limit storage used.
+    public class HeightmapTerrainData : TerrainData
+    {
+        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
+        private static string LogHeader = "[HEIGHTMAP TERRAIN DATA]";
+
+        // TerrainData.this[x, y]
+        public override float this[int x, int y]
+        {
+            get { return FromCompressedHeight(m_heightmap[x, y]); }
+            set {
+                short newVal = ToCompressedHeight(value);
+                if (m_heightmap[x, y] != newVal)
+                {
+                    m_heightmap[x, y] = newVal;
+                    m_taint[x / Constants.TerrainPatchSize, y / Constants.TerrainPatchSize] = true;
+                }
+            }
+        }
+
+        // TerrainData.this[x, y, z]
+        public override float this[int x, int y, int z]
+        {
+            get { return this[x, y]; }
+            set { this[x, y] = value; }
+        }
+
+        // TerrainData.ClearTaint
+        public override void ClearTaint()
+        {
+            IsTainted = false;
+            for (int ii = 0; ii < m_taint.GetLength(0); ii++)
+                for (int jj = 0; jj < m_taint.GetLength(1); jj++)
+                    m_taint[ii, jj] = false;
+        }
+
+        // TerrainData.ClearLand
+        public override void ClearLand()
+        {
+            ClearLand(DefaultTerrainHeight);
+        }
+        // TerrainData.ClearLand(float)
+        public override void ClearLand(float pHeight)
+        {
+            short flatHeight = ToCompressedHeight(pHeight);
+            for (int xx = 0; xx < SizeX; xx++)
+                for (int yy = 0; yy < SizeY; yy++)
+                    m_heightmap[xx, yy] = flatHeight;
+        }
+
+        public override bool IsTaintedAt(int xx, int yy)
+        {
+            int tx = xx / Constants.TerrainPatchSize;
+            int ty = yy / Constants.TerrainPatchSize;
+            bool ret =  m_taint[tx, ty];
+            m_taint[tx, ty] = false;
+            return ret;
+        }
+
+        // TerrainData.GetDatabaseBlob
+        // The user wants something to store in the database.
+        public override bool GetDatabaseBlob(out int DBRevisionCode, out Array blob)
+        {
+            bool ret = false;
+            if (SizeX == Constants.RegionSize && SizeY == Constants.RegionSize)
+            {
+                DBRevisionCode = (int)DBTerrainRevision.Legacy256;
+                blob = ToLegacyTerrainSerialization();
+                ret = true;
+            }
+            else
+            {
+                DBRevisionCode = (int)DBTerrainRevision.Compressed2D;
+                blob = ToCompressedTerrainSerialization();
+                ret = true;
+            }
+            return ret;
+        }
+
+        // TerrainData.CompressionFactor
+        private float m_compressionFactor = 100.0f;
+        public override float CompressionFactor { get { return m_compressionFactor; } }
+
+        // TerrainData.GetCompressedMap
+        public override short[] GetCompressedMap()
+        {
+            short[] newMap = new short[SizeX * SizeY];
+
+            int ind = 0;
+            for (int xx = 0; xx < SizeX; xx++)
+                for (int yy = 0; yy < SizeY; yy++)
+                    newMap[ind++] = m_heightmap[xx, yy];
+
+            return newMap;
+
+        }
+        // TerrainData.Clone
+        public override TerrainData Clone()
+        {
+            HeightmapTerrainData ret = new HeightmapTerrainData(SizeX, SizeY, SizeZ);
+            ret.m_heightmap = (short[,])this.m_heightmap.Clone();
+            return ret;
+        }
+
+        // TerrainData.GetDoubles
+        public override double[,] GetDoubles()
+        {
+            double[,] ret = new double[SizeX, SizeY];
+            for (int xx = 0; xx < SizeX; xx++)
+                for (int yy = 0; yy < SizeY; yy++)
+                    ret[xx, yy] = FromCompressedHeight(m_heightmap[xx, yy]);
+
+            return ret;
+        }
+
+
+        // =============================================================
+
+        private short[,] m_heightmap;
+        // Remember subregions of the heightmap that has changed.
+        private bool[,] m_taint;
+
+        // To save space (especially for large regions), keep the height as a short integer
+        //    that is coded as the float height times the compression factor (usually '100'
+        //    to make for two decimal points).
+        public short ToCompressedHeight(double pHeight)
+        {
+            return (short)(pHeight * CompressionFactor);
+        }
+
+        public float FromCompressedHeight(short pHeight)
+        {
+            return ((float)pHeight) / CompressionFactor;
+        }
+
+        // To keep with the legacy theme, create an instance of this class based on the
+        //     way terrain used to be passed around.
+        public HeightmapTerrainData(double[,] pTerrain)
+        {
+            SizeX = pTerrain.GetLength(0);
+            SizeY = pTerrain.GetLength(1);
+            SizeZ = (int)Constants.RegionHeight;
+            m_compressionFactor = 100.0f;
+
+            m_heightmap = new short[SizeX, SizeY];
+            for (int ii = 0; ii < SizeX; ii++)
+            {
+                for (int jj = 0; jj < SizeY; jj++)
+                {
+                    m_heightmap[ii, jj] = ToCompressedHeight(pTerrain[ii, jj]);
+
+                }
+            }
+            // m_log.DebugFormat("{0} new by doubles. sizeX={1}, sizeY={2}, sizeZ={3}", LogHeader, SizeX, SizeY, SizeZ);
+
+            m_taint = new bool[SizeX / Constants.TerrainPatchSize, SizeY / Constants.TerrainPatchSize];
+            ClearTaint();
+        }
+
+        // Create underlying structures but don't initialize the heightmap assuming the caller will immediately do that
+        public HeightmapTerrainData(int pX, int pY, int pZ)
+        {
+            SizeX = pX;
+            SizeY = pY;
+            SizeZ = pZ;
+            m_compressionFactor = 100.0f;
+            m_heightmap = new short[SizeX, SizeY];
+            m_taint = new bool[SizeX / Constants.TerrainPatchSize, SizeY / Constants.TerrainPatchSize];
+            // m_log.DebugFormat("{0} new by dimensions. sizeX={1}, sizeY={2}, sizeZ={3}", LogHeader, SizeX, SizeY, SizeZ);
+            ClearTaint();
+            ClearLand(0f);
+        }
+
+        public HeightmapTerrainData(short[] cmap, float pCompressionFactor, int pX, int pY, int pZ) : this(pX, pY, pZ)
+        {
+            m_compressionFactor = pCompressionFactor;
+            int ind = 0;
+            for (int xx = 0; xx < SizeX; xx++)
+                for (int yy = 0; yy < SizeY; yy++)
+                    m_heightmap[xx, yy] = cmap[ind++];
+            // m_log.DebugFormat("{0} new by compressed map. sizeX={1}, sizeY={2}, sizeZ={3}", LogHeader, SizeX, SizeY, SizeZ);
+        }
+
+        // Create a heighmap from a database blob
+        public HeightmapTerrainData(int pSizeX, int pSizeY, int pSizeZ, int pFormatCode, byte[] pBlob) : this(pSizeX, pSizeY, pSizeZ)
+        {
+            switch ((DBTerrainRevision)pFormatCode)
+            {
+                case DBTerrainRevision.Compressed2D:
+                    FromCompressedTerrainSerialization(pBlob);
+                    m_log.DebugFormat("{0} HeightmapTerrainData create from Compressed2D serialization. Size=<{1},{2}>", LogHeader, SizeX, SizeY);
+                    break;
+                default:
+                    FromLegacyTerrainSerialization(pBlob);
+                    m_log.DebugFormat("{0} HeightmapTerrainData create from legacy serialization. Size=<{1},{2}>", LogHeader, SizeX, SizeY);
+                    break;
+            }
+        }
+
+        // Just create an array of doubles. Presumes the caller implicitly knows the size.
+        public Array ToLegacyTerrainSerialization()
+        {
+            Array ret = null;
+
+            using (MemoryStream str = new MemoryStream((int)Constants.RegionSize * (int)Constants.RegionSize * sizeof(double)))
+            {
+                using (BinaryWriter bw = new BinaryWriter(str))
+                {
+                    for (int xx = 0; xx < Constants.RegionSize; xx++)
+                    {
+                        for (int yy = 0; yy < Constants.RegionSize; yy++)
+                        {
+                            double height = this[xx, yy];
+                            if (height == 0.0)
+                                height = double.Epsilon;
+                            bw.Write(height);
+                        }
+                    }
+                }
+                ret = str.ToArray();
+            }
+            return ret;
+        }
+
+        // Just create an array of doubles. Presumes the caller implicitly knows the size.
+        public void FromLegacyTerrainSerialization(byte[] pBlob)
+        {
+            // In case database info doesn't match real terrain size, initialize the whole terrain.
+            ClearLand();
+
+            using (MemoryStream mstr = new MemoryStream(pBlob))
+            {
+                using (BinaryReader br = new BinaryReader(mstr))
+                {
+                    for (int xx = 0; xx < (int)Constants.RegionSize; xx++)
+                    {
+                        for (int yy = 0; yy < (int)Constants.RegionSize; yy++)
+                        {
+                            float val = (float)br.ReadDouble();
+                            if (xx < SizeX && yy < SizeY)
+                                m_heightmap[xx, yy] = ToCompressedHeight(val);
+                        }
+                    }
+                }
+                ClearTaint();
+            }
+        }
+        
+        // See the reader below.
+        public Array ToCompressedTerrainSerialization()
+        {
+            Array ret = null;
+            using (MemoryStream str = new MemoryStream((3 * sizeof(Int32)) + (SizeX * SizeY * sizeof(Int16))))
+            {
+                using (BinaryWriter bw = new BinaryWriter(str))
+                {
+                    bw.Write((Int32)DBTerrainRevision.Compressed2D);
+                    bw.Write((Int32)SizeX);
+                    bw.Write((Int32)SizeY);
+                    bw.Write((Int32)CompressionFactor);
+                    for (int yy = 0; yy < SizeY; yy++)
+                        for (int xx = 0; xx < SizeX; xx++)
+                        {
+                            bw.Write((Int16)m_heightmap[xx, yy]);
+                        }
+                }
+                ret = str.ToArray();
+            }
+            return ret;
+        }
+
+        // Initialize heightmap from blob consisting of:
+        //    int32, int32, int32, int32, int16[]
+        //    where the first int32 is format code, next two int32s are the X and y of heightmap data and
+        //    the forth int is the compression factor for the following int16s
+        // This is just sets heightmap info. The actual size of the region was set on this instance's
+        //    creation and any heights not initialized by theis blob are set to the default height.
+        public void FromCompressedTerrainSerialization(byte[] pBlob)
+        {
+            Int32 hmFormatCode, hmSizeX, hmSizeY, hmCompressionFactor;
+
+            using (MemoryStream mstr = new MemoryStream(pBlob))
+            {
+                using (BinaryReader br = new BinaryReader(mstr))
+                {
+                    hmFormatCode = br.ReadInt32();
+                    hmSizeX = br.ReadInt32();
+                    hmSizeY = br.ReadInt32();
+                    hmCompressionFactor = br.ReadInt32();
+
+                    m_compressionFactor = hmCompressionFactor;
+
+                    // In case database info doesn't match real terrain size, initialize the whole terrain.
+                    ClearLand();
+
+                    for (int yy = 0; yy < hmSizeY; yy++)
+                    {
+                        for (int xx = 0; xx < hmSizeX; xx++)
+                        {
+                            Int16 val = br.ReadInt16();
+                            if (xx < SizeX && yy < SizeY)
+                                m_heightmap[xx, yy] = val;
+                        }
+                    }
+                }
+                ClearTaint();
+
+                m_log.InfoFormat("{0} Read compressed 2d heightmap. Heightmap size=<{1},{2}>. Region size=<{3},{4}>. CompFact={5}",
+                                LogHeader, hmSizeX, hmSizeY, SizeX, SizeY, hmCompressionFactor);
+            }
+        }
+    }
+}