Add a .wsa file reader.

OpenRA.Mods.Cnc/FileFormats/WsaReader.cs

@@ -0,0 +1,136 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2021 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, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System;
+using System.IO;
+using OpenRA.Video;
+
+namespace OpenRA.Mods.Cnc.FileFormats
+{
+	public class WsaReader : IVideo
+	{
+		readonly Stream stream;
+
+		public ushort Frames { get { return frameCount; } }
+		public byte Framerate { get { return 1; } }
+		public ushort Width { get { return width; } }
+		public ushort Height { get { return height; } }
+
+		readonly ushort frameCount;
+		readonly ushort width;
+		readonly ushort height;
+		readonly uint[] palette;
+		readonly uint[] frameOffsets;
+
+		uint[,] coloredFrameData;
+		public uint[,] FrameData { get { return coloredFrameData; } }
+
+		int currentFrame;
+		byte[] previousFrameData;
+		byte[] currentFrameData;
+
+		public byte[] AudioData { get { return null; } }
+		public int CurrentFrame { get { return currentFrame; } }
+		public int SampleRate { get { return 0; } }
+		public int SampleBits { get { return 0; } }
+		public int AudioChannels { get { return 0; } }
+		public bool HasAudio { get { return false; } }
+
+		public WsaReader(Stream stream)
+		{
+			this.stream = stream;
+
+			frameCount = stream.ReadUInt16();
+
+			var x = stream.ReadUInt16();
+			var y = stream.ReadUInt16();
+
+			width = stream.ReadUInt16();
+			height = stream.ReadUInt16();
+
+			var delta = stream.ReadUInt16() + 37;
+			var flags = stream.ReadUInt16();
+
+			frameOffsets = new uint[frameCount + 2];
+			for (var i = 0; i < frameOffsets.Length; i++)
+				frameOffsets[i] = stream.ReadUInt32();
+
+			if (flags == 1)
+			{
+				palette = new uint[256];
+				for (var i = 0; i < palette.Length; i++)
+				{
+					var r = (byte)(stream.ReadByte() << 2);
+					var g = (byte)(stream.ReadByte() << 2);
+					var b = (byte)(stream.ReadByte() << 2);
+
+					// Replicate high bits into the (currently zero) low bits.
+					r |= (byte)(r >> 6);
+					g |= (byte)(g >> 6);
+					b |= (byte)(b >> 6);
+
+					palette[i] = (uint)((255 << 24) | (r << 16) | (g << 8) | b);
+				}
+
+				for (var i = 0; i < frameOffsets.Length; i++)
+					frameOffsets[i] += 768;
+			}
+
+			Reset();
+		}
+
+		public void Reset()
+		{
+			currentFrame = 0;
+			previousFrameData = null;
+			LoadFrame();
+		}
+
+		public void AdvanceFrame()
+		{
+			previousFrameData = currentFrameData;
+			currentFrame++;
+			LoadFrame();
+		}
+
+		void LoadFrame()
+		{
+			if (currentFrame >= frameCount)
+				return;
+
+			stream.Seek(frameOffsets[currentFrame], SeekOrigin.Begin);
+
+			var dataLength = frameOffsets[currentFrame + 1] - frameOffsets[currentFrame];
+
+			var rawData = StreamExts.ReadBytes(stream, (int)dataLength);
+			var intermediateData = new byte[width * height];
+
+			// Format80 decompression
+			LCWCompression.DecodeInto(rawData, intermediateData);
+
+			// and Format40 decompression
+			currentFrameData = new byte[width * height];
+			if (previousFrameData == null)
+				Array.Clear(currentFrameData, 0, currentFrameData.Length);
+			else
+				Array.Copy(previousFrameData, currentFrameData, currentFrameData.Length);
+
+			XORDeltaCompression.DecodeInto(intermediateData, currentFrameData, 0);
+
+			var c = 0;
+			var frameSize = Exts.NextPowerOf2(Math.Max(width, height));
+			coloredFrameData = new uint[frameSize, frameSize];
+			for (var y = 0; y < height; y++)
+				for (var x = 0; x < width; x++)
+					coloredFrameData[y, x] = palette[currentFrameData[c++]];
+		}
+	}
+}

OpenRA.Mods.Cnc/VideoLoaders/WsaLoader.cs

@@ -0,0 +1,66 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2021 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, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System.IO;
+using System.Linq;
+using OpenRA.Mods.Cnc.FileFormats;
+using OpenRA.Video;
+
+namespace OpenRA.Mods.Cnc.VideoLoaders
+{
+	public class WsaLoader : IVideoLoader
+	{
+		public bool TryParseVideo(Stream s, out IVideo video)
+		{
+			video = null;
+
+			if (!IsWsa(s))
+				return false;
+
+			video = new WsaReader(s);
+			return true;
+		}
+
+		bool IsWsa(Stream s)
+		{
+			var start = s.Position;
+
+			var frames = s.ReadUInt16();
+
+			var x = s.ReadUInt16();
+			var y = s.ReadUInt16();
+			var width = s.ReadUInt16();
+			var height = s.ReadUInt16();
+
+			if (width <= 0 || height <= 0)
+				return false;
+
+			var delta = s.ReadUInt16() + 37;
+
+			var flags = s.ReadUInt16();
+
+			var offsets = new uint[frames + 2];
+			for (var i = 0; i < offsets.Length; i++)
+				offsets[i] = s.ReadUInt32();
+
+			if (flags == 1)
+			{
+				var palette = StreamExts.ReadBytes(s, 768);
+				for (var i = 0; i < offsets.Length; i++)
+					offsets[i] += 768;
+			}
+
+			s.Position = start;
+
+			return s.Length == offsets.Last();
+		}
+	}
+}