Initial commit for SRTMv4 usage.

src/SRTM/SRTM.csproj

@@ -27,4 +27,8 @@
     <PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
   </ItemGroup>
 
+  <ItemGroup>
+    <Folder Include="Sources\CGIAR\" />
+  </ItemGroup>
+
 </Project>

src/SRTM/Sources/CGIAR/AsciiGridFile.cs

@@ -0,0 +1,119 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Diagnostics;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+
+namespace SRTM.Sources.CGIAR
+{
+    /// <summary>
+    /// An Esri grid is a raster GIS file format developed by Esri, which has two formats:
+    /// 
+    /// A proprietary binary format, also known as an ARC/INFO GRID, ARC GRID and many other variations
+    /// A non-proprietary ASCII format, also known as an ARC/INFO ASCII GRID
+    /// The formats were introduced for ARC/INFO. The binary format is widely used within Esri programs, such /// as ArcGIS, while the ASCII format is used as an exchange, or export format, due to the simple and portable ASCII file structure.
+    /// 
+    /// The grid defines geographic space as an array of equally sized square grid points arranged in rows and /// columns. Each grid point stores a numeric value that represents a geographic attribute (such as elevation or surface slope) for that unit of space. Each grid cell is referenced by its x,y coordinate location.
+    /// https://en.wikipedia.org/wiki/Esri_grid
+    /// Spec: http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//009t0000000w000000
+    /// </summary>
+    public class ASCIIGridFile
+    {
+        private FileStream _fileStream;
+        private StreamReader _streamReader;
+        private readonly string _filename;
+        private static char[] SEPARATOR = new char[] { ' ' };
+
+        List<List<string>> _data = null;
+        private static Dictionary<string, List<List<string>>> _tempCache = new Dictionary<string, List<List<string>>>();
+
+        public ASCIIGridFile(string fileName)
+        {
+            this._filename = fileName;
+            _fileStream = new FileStream(_filename, FileMode.Open, FileAccess.Read, FileShare.Read);
+            _streamReader = new StreamReader(_fileStream, Encoding.ASCII);
+        }
+        public float GetElevationAtPoint(FileMetadata metadata, int x, int y)
+        {
+            if (_data == null)
+            {
+                ReadAllFile(metadata);
+            }
+
+            string strXValue = _data[y][x];
+
+            float elevation = float.Parse(strXValue, CultureInfo.InvariantCulture);
+            return elevation;
+
+        }
+
+        private void ReadAllFile(FileMetadata metadata)
+        {
+            if (_tempCache.ContainsKey(_filename))
+            {
+                _data = _tempCache[_filename];
+                return;
+            }
+            string curLine = null;
+            _fileStream.Seek(0, SeekOrigin.Begin);
+
+            // skip header
+            for (int i = 1; i <= 6 /* + (y - 1)*/; i++)
+            {
+                curLine = _streamReader.ReadLine();
+            }
+
+            _data = new List<List<string>>(metadata.Height);
+            while (!_streamReader.EndOfStream)
+            {
+                var line = _streamReader.ReadLine().Trim();
+
+                var values = new List<string>(metadata.Width);
+                var current = string.Empty;
+                foreach (char c in line)
+                {
+                    if (c == ' ')
+                    {
+                        values.Add(current);
+                        current = string.Empty;
+                    }
+                    else
+                    {
+                        current += c;
+                    }
+                }
+                values.Add(current);
+                _data.Add(values);
+            }
+            _tempCache[_filename] = _data;
+        }
+
+        #region IDisposable Support
+        private bool disposedValue = false; 
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (!disposedValue)
+            {
+                if (disposing)
+                {
+                    _streamReader?.Dispose();
+                    _fileStream?.Dispose();
+                }
+
+                disposedValue = true;
+            }
+        }
+
+        // Ce code est ajouté pour implémenter correctement le modèle supprimable.
+        public void Dispose()
+        {
+            Dispose(true);
+        }
+
+
+        #endregion
+    }
+}

src/SRTM/Sources/CGIAR/CGIARSource.cs

@@ -0,0 +1,50 @@
+// The MIT License (MIT)
+
+// Copyright (c) 2017 Alpine Chough Software, Ben Abelshausen
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+using SRTM.Logging;
+
+namespace SRTM.Sources.CGIAR
+{
+    /// <summary>
+    /// Defines an CGIAR source of data for SRTMv4.
+    /// </summary>
+    public class CGIARSource : ISRTMSource
+    {
+        /// <summary>
+        /// The source of the data.
+        /// </summary>
+        public const string SOURCE = @"http://srtm.csi.cgiar.org/wp-content/uploads/files/srtm_5x5/ASCII";
+
+        /// <summary>
+        /// Gets the missing cell.
+        /// </summary>
+        public bool GetMissingCell(string path, string name)
+        {
+            var filename = name + ".zip";
+            var local = System.IO.Path.Combine(path, filename);
+
+            var Logger = LogProvider.For<SRTMData>();
+            Logger.Info($"Downloading {name} ...");
+            return SourceHelpers.Download(local, SOURCE + "/" + filename);
+        }
+    }
+}

src/SRTM/Sources/CGIAR/FileMetadata.cs

@@ -0,0 +1,8 @@
+namespace SRTM.Sources.CGIAR
+{
+    public class FileMetadata
+    {
+        public int Height { get; set; }
+        public int Width { get; set; }
+    }
+}