Automap/Subsystems/Snapshot.cs

   1 using System;
   2 using System.Collections.Generic;
   3 using System.Diagnostics;
   4 using System.IO;
   5 using System.Linq;
   6 using System.Threading;
   7 using System.Threading.Tasks;
   8
   9 using Hjg.Pngcs;
  10 using Hjg.Pngcs.Chunks;
  11 using Vintagestory.API.Common;
  12
  13 namespace Automap
  14 {
  15         public class Snapshotter
  16         {
  17                 public readonly int chunkSize;
  18                 public string fileName;
  19                 public string chunkPath;
  20                 public ColumnsMetadata cols;
  21                 //TODO: Refactor - so Edges are set at construction time, as ColumnsMetadata is async updating in real time!
  22                 public int NorthEdge => cols.North_mostChunk;
  23                 public int WestEdge => cols.West_mostChunk;
  24                 public int Width => (cols.East_mostChunk - WestEdge + 1);
  25                 public int Height => (cols.South_mostChunk - NorthEdge + 1);
  26
  27
  28                 public Snapshotter(string path, ColumnsMetadata cols, int chunkSize, int worldSeed)
  29                 {
  30                         this.fileName = Path.Combine(path, $"snapshot_{worldSeed}.png");
  31                         this.chunkPath = Path.Combine(path, AutomapSystem._chunkPath);
  32                         this.cols = cols;
  33                         this.chunkSize = chunkSize;
  34                 }
  35
  36                 /// <summary>
  37                 /// takes a snapshot. this should be called from an extra thread.
  38                 /// </summary>
  39                 public async void Take()
  40                 {
  41
  42                         ImageInfo info = new ImageInfo(Width * chunkSize, Height * chunkSize, 8, false);
  43
  44                         PngWriter snapWriter = FileHelper.CreatePngWriter(fileName, info, true);
  45
  46                         PngMetadata meta = snapWriter.GetMetadata( );
  47                         meta.SetTimeNow( );
  48                         var transparencyChunk = meta.CreateTRNSChunk( );
  49                         transparencyChunk.SetRGB(0, 0, 0);//CHECK: This is pure black.
  50                         meta.SetText("Northmost", NorthEdge.ToString("D"));
  51                         meta.SetText("Eastmost", WestEdge.ToString("D"));
  52                         meta.SetText("Width", Width.ToString("D"));
  53                         meta.SetText("Height", Height.ToString("D"));
  54
  55
  56
  57                         /*
  58                         Red:   2 bytes, range 0 .. (2^bitdepth)-1
  59                         Green: 2 bytes, range 0 .. (2^bitdepth)-1
  60                         Blue:  2 bytes, range 0 .. (2^bitdepth)-1
  61                         */
  62
  63
  64                         snapWriter.CompLevel = 5;
  65                         snapWriter.CompressionStrategy = Hjg.Pngcs.Zlib.EDeflateCompressStrategy.Filtered;
  66
  67
  68
  69                         var orderedList =
  70                                 from ch in cols
  71                                 group ch by ch.Location.Y into g
  72                                 orderby g.Key
  73                                 select g;
  74                         // that sorts things in ascending order so we can only create (chunkSize) lines at once
  75                         int row = 0, lastPosY = 0, posY = 0;
  76                         foreach (var chunkGroup in orderedList)
  77                         {
  78                                 // oh god here we go...
  79                                 posY = chunkGroup.Key - NorthEdge;
  80                                 var delta = posY - lastPosY;
  81                                 lastPosY = posY;
  82
  83                                 // if there is more than 1 blank step then the gap needs to be filled.
  84                                 for (int i = 1; i < delta; i++)
  85                                 {
  86                                         byte[] blankLine = new byte[info.BytesPerRow];
  87                                         for (int j = 0; j < chunkSize; j++)
  88                                                 snapWriter.WriteRowByte(blankLine, row++);
  89                                 }
  90
  91                                 var inGroup = (await ReadAllInGroup(chunkGroup)).ToArray();
  92
  93                                 for (int r = 0; r < chunkSize; r++)
  94                                 {
  95                                         var line = new byte[info.BytesPerRow];
  96                                         for (int chunk = 0; chunk < inGroup.Length; chunk++)
  97                                         {
  98                                                 var posX = inGroup[chunk].Key * chunkSize * info.BytesPixel;
  99                                                 inGroup[chunk].Value?[r].CopyTo(line, posX);
 100                                         }
 101                                         snapWriter.WriteRowByte(line, row++);
 102                                 }
 103                         }
 104                         snapWriter.ShouldCloseStream = true;
 105                         try
 106                         {
 107                                 snapWriter.End();
 108                         }
 109                         catch (Exception)
 110                         {
 111                                 Console.WriteLine("Snapshot exception!");
 112                         }
 113                 }
 114
 115                 private async Task<Dictionary<int, byte[][]>> ReadAllInGroup(IGrouping<int, ColumnMeta> group)
 116                 {
 117                         var taskGroup = new Dictionary<int, byte[][]>(group.Count());
 118                         foreach (var shardMeta in group)
 119                         {
 120                                 var shardPath = Path.Combine(chunkPath, $"{shardMeta.Location.X}_{shardMeta.Location.Y}.png");
 121                                 taskGroup.Add(shardMeta.Location.X - WestEdge, await ReadNoThrow(shardPath));
 122                         }
 123                         return taskGroup;
 124                 }
 125
 126                 private async Task<byte[][]> ReadNoThrow(string readPath)
 127                 {
 128                         try
 129                         {
 130                                 return await Task.Run(() => FileHelper.CreatePngReader(readPath).ReadRowsByte().ScanlinesB);
 131                         }
 132                         catch (Exception e)
 133                         {
 134                                 Console.WriteLine(e.Message);
 135                                 return null;
 136                         } // do nothing on error
 137                 }
 138         }
 139 }