Move ShpD2 sprite loading into Mods.Common.

OpenRA.Mods.Common/SpriteLoaders/ShpD2Loader.cs

@@ -0,0 +1,168 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2014 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation. For more information,
+ * see COPYING.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using System.IO;
+using System.Linq;
+using OpenRA.FileFormats;
+using OpenRA.Graphics;
+
+namespace OpenRA.Mods.Common.SpriteLoaders
+{
+	public class ShpD2Loader : ISpriteLoader
+	{
+		[Flags] enum FormatFlags : int
+		{
+			PaletteTable = 1,
+			SkipFormat80 = 2,
+			VariableLengthTable = 4
+		}
+
+		class ShpD2Frame : ISpriteFrame
+		{
+			public Size Size { get; private set; }
+			public Size FrameSize { get { return Size; } }
+			public float2 Offset { get { return float2.Zero; } }
+			public byte[] Data { get; set; }
+			public bool DisableExportPadding { get { return false; } }
+
+			public ShpD2Frame(Stream s)
+			{
+				var flags = (FormatFlags)s.ReadUInt16();
+				s.Position += 1;
+				var width = s.ReadUInt16();
+				var height = s.ReadUInt8();
+				Size = new Size(width, height);
+
+				// Subtract header size
+				var dataLeft = s.ReadUInt16() - 10;
+				var dataSize = s.ReadUInt16();
+
+				byte[] table;
+				if ((flags & FormatFlags.PaletteTable) != 0)
+				{
+					var n = (flags & FormatFlags.VariableLengthTable) != 0 ? s.ReadUInt8() : (byte)16;
+					table = new byte[n];
+					for (var i = 0; i < n; i++)
+						table[i] = s.ReadUInt8();
+
+					dataLeft -= n;
+				}
+				else
+				{
+					table = new byte[256];
+					for (var i = 0; i < 256; i++)
+						table[i] = (byte)i;
+					table[1] = 0x7f;
+					table[2] = 0x7e;
+					table[3] = 0x7d;
+					table[4] = 0x7c;
+				}
+
+				Data = new byte[width * height];
+
+				// Decode image data
+				var compressed = s.ReadBytes(dataLeft);
+				if ((flags & FormatFlags.SkipFormat80) == 0)
+				{
+					var temp = new byte[dataSize];
+					Format80.DecodeInto(compressed, temp);
+					compressed = temp;
+				}
+
+				Format2.DecodeInto(compressed, Data, 0);
+
+				// Lookup values in lookup table
+				for (var j = 0; j < Data.Length; j++)
+					Data[j] = table[Data[j]];
+			}
+		}
+
+		bool IsShpD2(Stream s)
+		{
+			var start = s.Position;
+
+			// First word is the image count
+			var imageCount = s.ReadUInt16();
+			if (imageCount == 0)
+			{
+				s.Position = start;
+				return false;
+			}
+
+			// Test for two vs four byte offset
+			var testOffset = s.ReadUInt32();
+			var offsetSize = (testOffset & 0xFF0000) > 0 ? 2 : 4;
+
+			// Last offset should point to the end of file
+			var finalOffset = start + 2 + offsetSize * imageCount;
+			if (finalOffset > s.Length)
+			{
+				s.Position = start;
+				return false;
+			}
+
+			s.Position = finalOffset;
+			var eof = offsetSize == 2 ? s.ReadUInt16() : s.ReadUInt32();
+			if (eof + 2 != s.Length)
+			{
+				s.Position = start;
+				return false;
+			}
+
+			// Check the format flag on the first frame
+			var b = s.ReadUInt16();
+			s.Position = start;
+			return b == 5 || b <= 3;
+		}
+
+		ShpD2Frame[] ParseFrames(Stream s)
+		{
+			var start = s.Position;
+
+			var imageCount = s.ReadUInt16();
+
+			// Last offset is pointer to end of file.
+			var offsets = new uint[imageCount + 1];
+			var temp = s.ReadUInt32();
+
+			// If fourth byte in file is non-zero, the offsets are two bytes each.
+			var twoByteOffset = (temp & 0xFF0000) > 0;
+			s.Position = 2;
+
+			for (var i = 0; i < imageCount + 1; i++)
+				offsets[i] = (twoByteOffset ? s.ReadUInt16() : s.ReadUInt32()) + 2;
+
+			var frames = new ShpD2Frame[imageCount];
+			for (var i = 0; i < frames.Length; i++)
+			{
+				s.Position = offsets[i];
+				frames[i] = new ShpD2Frame(s);
+			}
+
+			s.Position = start;
+			return frames;
+		}
+
+		public bool TryParseSprite(Stream s, out ISpriteFrame[] frames)
+		{
+			if (!IsShpD2(s))
+			{
+				frames = null;
+				return false;
+			}
+
+			frames = ParseFrames(s);
+			return true;
+		}
+	}
+}