Second commit

Assets/Tremble/IO/WAD/WadParser.cs

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+//
+// This file is part of the Tremble package by Tiny Goose.
+// Copyright (c) 2024-2026 TinyGoose Ltd., All Rights Reserved.
+//
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using UnityEngine;
+using UnityEngine.Experimental.Rendering;
+
+namespace TinyGoose.Tremble
+{
+	public class WadParser
+	{
+		private readonly StreamReadIO m_Stream;
+
+		public WadParser(string filename)
+		{
+			m_Stream = new(filename);
+		}
+
+		public void WriteTextureToFile(in WadEntry entry, string outFile)
+		{
+			m_Stream.Seek(entry.Address);
+
+			string name = m_Stream.ReadString(16);
+			int width = m_Stream.ReadInt32();
+			int height = m_Stream.ReadInt32();
+			m_Stream.SkipBytes(16);
+
+			byte[] palettedTextureData = m_Stream.ReadBytes(width * height);
+			byte[] rgbTextureData = new byte[palettedTextureData.Length * 3];
+
+			// Copy paletted to RGB, flipping as we go
+			for (int x = 0; x < width; x++)
+			{
+				for (int y = 0; y < height; y++)
+				{
+					int readOffset = y * width + x;
+
+					int invY = height - y - 1;
+					int writeOffset = (invY * width + x) * 3;
+
+					ref Color32 colour = ref WadPalette.QuakePalette.Get(palettedTextureData[readOffset]);
+
+					rgbTextureData[writeOffset + 0] = colour.r;
+					rgbTextureData[writeOffset + 1] = colour.g;
+					rgbTextureData[writeOffset + 2] = colour.b;
+				}
+			}
+
+			byte[] pngBytes = ImageConversion.EncodeArrayToPNG(rgbTextureData, GraphicsFormat.R8G8B8_UNorm, (uint)width, (uint)height);
+			File.WriteAllBytes(outFile, pngBytes);
+		}
+
+		public WadFile Parse()
+		{
+			m_Stream.Seek(0);
+
+			string magic = new(m_Stream.ReadChars(4));
+			if (!magic.EqualsInvariant("wad2"))
+			{
+				Debug.LogError($"File was not a WAD2 :(");
+				return default;
+			}
+
+			int numEntries = m_Stream.ReadInt32();
+			int dirOffset = m_Stream.ReadInt32();
+
+			m_Stream.Seek(dirOffset);
+
+			List<WadEntry> entries = new(numEntries);
+			for (int entryIdx = 0; entryIdx < numEntries; entryIdx++)
+			{
+				int entryAddress = m_Stream.ReadInt32();
+				int entrySize = m_Stream.ReadInt32();
+				m_Stream.SkipBytes(4);
+				char type = (char)m_Stream.ReadByte();
+				m_Stream.SkipBytes(3);
+				string name = new(m_Stream.ReadString(16));
+
+				// Skip anything that's not a texture
+				if (type != 'D')
+					continue;
+
+				entries.Add(new()
+				{
+					Address = entryAddress,
+					Size = entrySize,
+					Type = type,
+					Name = name.Replace('*', '_') // * is not a valid name for an asset!
+				});
+			}
+
+			return new()
+			{
+				Entries = entries
+			};
+		}
+	}
+}