asc gzip

dem-net · Aug 13, 2021 · 168cd8e · 168cd8e
1 parent b26675e
commit 168cd8e
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Showing 5 changed files with 35 additions and 5 deletions.
diff --git a/DEM.Net.Core/IO/Raster/AsciiGridFile.cs b/DEM.Net.Core/IO/Raster/AsciiGridFile.cs
@@ -3,6 +3,7 @@
 using System.Diagnostics;
 using System.Globalization;
 using System.IO;
+using System.IO.Compression;
 using System.Linq;
 using System.Text;
 
@@ -23,17 +24,26 @@ public class ASCIIGridFile : IRasterFile
     {
         private FileStream _fileStream;
         private StreamReader _streamReader;
+        private GZipStream _gzipStream;
         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)
+        public ASCIIGridFile(string fileName, bool gzip)
         {
             this._filename = fileName;
             _fileStream = new FileStream(_filename, FileMode.Open, FileAccess.Read, FileShare.Read);
-            _streamReader = new StreamReader(_fileStream, Encoding.ASCII);
+            if (gzip)
+            {
+                _gzipStream = new GZipStream(_fileStream, CompressionMode.Decompress);
+                _streamReader = new StreamReader(_gzipStream, Encoding.ASCII);
+            }
+            else
+            {
+                _streamReader = new StreamReader(_fileStream, Encoding.ASCII);
+            }
         }
         public float GetElevationAtPoint(FileMetadata metadata, int x, int y)
         {
@@ -250,6 +260,7 @@ protected virtual void Dispose(bool disposing)
                     //_data = null;
                     _streamReader?.Dispose();
                     _fileStream?.Dispose();
+                    _gzipStream?.Dispose();
                 }
 
                 disposedValue = true;

diff --git a/DEM.Net.Core/Model/Datasets/DEMDataSet.cs b/DEM.Net.Core/Model/Datasets/DEMDataSet.cs
@@ -124,6 +124,19 @@ private static Dictionary<string, DEMDataSet> GetRegisteredDatasets()
                 Attribution = new Attribution(ATTRIBUTION_SUBJECT, "ETOPO1 - NOAA", "https://www.ngdc.noaa.gov/mgg/global/"
                     , "Amante, C. and B.W. Eakins, 2009. ETOPO1 1 Arc-Minute Global Relief Model: Procedures, Data Sources and Analysis. NOAA Technical Memorandum NESDIS NGDC-24. National Geophysical Data Center, NOAA. doi:10.7289/V5C8276M")
             });
+            datasets.Add("IGN_5m", new DEMDataSet()
+            {
+                Name = nameof(IGN_5m),
+                Description = "IGN RGE Alti 5 meter (France only)",
+                PublicUrl = "https://ign.fr",
+                DataSource = new LocalFileSystem(localDirectory: Path.Combine("Data", "IGN_5m_GZip")),
+                FileFormat = new DEMFileDefinition("Esri Ascii Grid (GZipped)", DEMFileType.ASCIIGridGzip, ".asc.gz", DEMFileRegistrationMode.Cell),
+                ResolutionMeters = 5,
+                PointsPerDegree = 21600,
+                NoDataValue = -99999,
+                SRID = 2154,
+                Attribution = new Attribution(ATTRIBUTION_SUBJECT, "IGN", "https://ign.fr", "https://www.etalab.gouv.fr/licence-ouverte-open-licence")
+            });
             //datasets.Add("IGN_5m", new DEMDataSet()
             //{
             //    Name = nameof(IGN_5m),
@@ -185,7 +198,7 @@ private static Dictionary<string, DEMDataSet> GetRegisteredDatasets()
             datasets.Add("GEBCO_2019", new DEMDataSet()
             {
                 Name = nameof(GEBCO_2019),
-                Description = "GEBCO’s gridded bathymetric data set, a global terrain model for ocean and land at 15 arc-second intervals",
+                Description = "400m with bathymetry",
                 PublicUrl = "https://www.gebco.net/data_and_products/gridded_bathymetry_data/gebco_2019/gebco_2019_info.html",
                 DataSource = new LocalFileSystem(localDirectory: Path.Combine("Data", "GEBCO_2019")),
                 FileFormat = new DEMFileDefinition("netCDF file", DEMFileType.CF_NetCDF, ".nc", DEMFileRegistrationMode.Cell),

diff --git a/DEM.Net.Core/Model/Raster/DEMFileType.cs b/DEM.Net.Core/Model/Raster/DEMFileType.cs
@@ -44,5 +44,10 @@ public enum DEMFileType
         /// </summary>
         /// <remarks>See https://en.wikipedia.org/wiki/Esri_grid</remarks>
         ASCIIGrid,
+        /// <summary>
+        /// ESRI ARC/INFO ASCII GRID
+        /// </summary>
+        /// <remarks>See https://en.wikipedia.org/wiki/Esri_grid</remarks>
+        ASCIIGridGzip,
     }
 }
diff --git a/DEM.Net.Core/Services/Raster/RasterService.cs b/DEM.Net.Core/Services/Raster/RasterService.cs
@@ -115,7 +115,8 @@ public IRasterFile OpenFile(string filePath, DEMFileType fileFormat)
             {
                 case DEMFileType.GEOTIFF: return new GeoTiff(filePath);
                 case DEMFileType.SRTM_HGT: return new HGTFile(filePath);
-                case DEMFileType.ASCIIGrid: return new ASCIIGridFile(filePath);
+                case DEMFileType.ASCIIGrid: return new ASCIIGridFile(filePath, gzip: false);
+                case DEMFileType.ASCIIGridGzip: return new ASCIIGridFile(filePath, gzip: true);
                 case DEMFileType.CF_NetCDF: return new NetCdfFile(filePath);
                 default:
                     throw new NotImplementedException($"{fileFormat} file format not implemented.");

diff --git a/DEM.Net.glTF/gtlfSharp/SharpGltfService.cs b/DEM.Net.glTF/gtlfSharp/SharpGltfService.cs
@@ -140,7 +140,7 @@ public ModelRoot AddTerrainMesh(ModelRoot model, HeightMap heightMap, PBRTexture
         {
             Triangulation triangulation = _meshService.TriangulateHeightMap(heightMap);
 
-            triangulation = _meshReducer.Decimate(triangulation, reduceFactor);
+            triangulation = reduceFactor < 1f ? _meshReducer.Decimate(triangulation, reduceFactor) : triangulation;
 
             model = AddTerrainMesh(model, triangulation, textures);