Optimize BiteArray convertors

Author: caetera

Writer/MzMlSpectrumWriter.cs

@@ -2455,21 +2455,29 @@ private ScanListType ConstructScanList(int scanNumber, Scan scan)
         /// <returns>the byte array</returns>
         private static byte[] Get64BitArray(ICollection<double> array)
         {
-            byte[] bytes;
+            Array bytes = Array.CreateInstance(typeof(byte), array.Count * sizeof(double));
 
-            using (var memoryStream = new MemoryStream())
+            if (BitConverter.IsLittleEndian) //should be for most modern systems, but maybe..
+            {
+                Buffer.BlockCopy(array.ToArray(), 0, bytes, 0, bytes.Length); //copy the buffer directly
+            }
+            else //swap byte order of all elements in array
             {
-                foreach (var doubleValue in array)
+                using (var memoryStream = new MemoryStream())
                 {
-                    var doubleValueByteArray = BitConverter.GetBytes(doubleValue);
-                    memoryStream.Write(doubleValueByteArray, 0, doubleValueByteArray.Length);
-                }
+                    foreach (var doubleValue in array)
+                    {
+                        var doubleValueByteArray = BitConverter.GetBytes(doubleValue);
+                        Array.Reverse(doubleValueByteArray);
+                        memoryStream.Write(doubleValueByteArray, 0, doubleValueByteArray.Length);
+                    }
 
-                memoryStream.Position = 0;
-                bytes = memoryStream.ToArray();
-            }
+                    memoryStream.Position = 0;
+                    bytes = memoryStream.ToArray();
+                }
+            }    
 
-            return bytes;
+            return (byte[])bytes;
         }
 
         /// <summary>
@@ -2482,17 +2490,13 @@ private static byte[] GetZLib64BitArray(ICollection<double> array)
             // zero length array encoded by GZip produces non-zero length array; some downstream tools do not like it
             if (array.Count == 0) return new byte[0];
 
-            byte[] bytes;
+            byte[] bytes = Get64BitArray(array);
 
             using (var memoryStream = new MemoryStream())
             using (var outZStream = new ZOutputStream(memoryStream, zlibConst.Z_DEFAULT_COMPRESSION))
             {
-                foreach (var doubleValue in array)
-                {
-                    var doubleValueByteArray = BitConverter.GetBytes(doubleValue);
-                    outZStream.Write(doubleValueByteArray, 0, doubleValueByteArray.Length);
-                }
-
+                    outZStream.Write(bytes, 0, bytes.Length);
+                
                 outZStream.finish();
                 memoryStream.Position = 0;
                 bytes = memoryStream.ToArray();

Writer/SpectrumWriter.cs

@@ -7,6 +7,7 @@
 using ThermoFisher.CommonCore.Data.Business;
 using ThermoFisher.CommonCore.Data.FilterEnums;
 using ThermoFisher.CommonCore.Data.Interfaces;
+using ThermoRawFileParser.Util;
 
 namespace ThermoRawFileParser.Writer
 {
@@ -41,7 +42,7 @@ public abstract class SpectrumWriter : ISpectrumWriter
         /// <summary>
         /// Precursor cache
         /// </summary>
-        private static Util.LimitedSizeDictionary<int, Scan> precursorCache;
+        private static LimitedSizeDictionary<int, Scan> precursorCache;
 
         /// <summary>
         /// Constructor.
@@ -50,7 +51,7 @@ public abstract class SpectrumWriter : ISpectrumWriter
         protected SpectrumWriter(ParseInput parseInput)
         {
             ParseInput = parseInput;
-            precursorCache = new Util.LimitedSizeDictionary<int, Scan>(10);
+            precursorCache = new LimitedSizeDictionary<int, Scan>(10);
         }
 
         /// <inheritdoc />