Added colors and textures

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

lib/features/map/vswap_parser.dart

@@ -0,0 +1,42 @@
+import 'dart:typed_data';
+
+import 'package:wolf_dart/classes/matrix.dart';
+
+class VswapParser {
+  /// Extracts the 64x64 wall textures from VSWAP.WL1
+  static List<Matrix<int>> parseWalls(ByteData vswap) {
+    // 1. Read Header
+    int chunks = vswap.getUint16(0, Endian.little);
+    int spriteStart = vswap.getUint16(2, Endian.little);
+    // int soundStart = vswap.getUint16(4, Endian.little); // We don't need this yet
+
+    // 2. Read Offsets (Where does each chunk start in the file?)
+    List<int> offsets = [];
+    for (int i = 0; i < spriteStart; i++) {
+      offsets.add(vswap.getUint32(6 + (i * 4), Endian.little));
+    }
+
+    // 3. Extract the Wall Textures
+    List<List<List<int>>> textures = [];
+
+    // Walls are chunks 0 through (spriteStart - 1)
+    for (int i = 0; i < spriteStart; i++) {
+      int offset = offsets[i];
+      if (offset == 0) continue; // Empty chunk
+
+      // Walls are always exactly 64x64 pixels (4096 bytes)
+      // Note: Wolf3D stores pixels in COLUMN-MAJOR order (Top to bottom, then left to right)
+      List<List<int>> texture = List.generate(64, (_) => List.filled(64, 0));
+
+      for (int x = 0; x < 64; x++) {
+        for (int y = 0; y < 64; y++) {
+          int byteIndex = offset + (x * 64) + y;
+          texture[x][y] = vswap.getUint8(byteIndex);
+        }
+      }
+      textures.add(texture);
+    }
+
+    return textures;
+  }
+}