Remove unused debug prints

project/code/Images/GifDecoder.cs

@@ -35,11 +35,9 @@ public class GifDecoder
             LogicalScreenHeight = reader.ReadUInt16();
             var flags = reader.ReadByte();
             HasGlobalColorTable = ((flags >> 7) & 0x1) != 0;
-            // Godot.GD.Print($"HALLO WE HAVE GLOBAL TABLE? {HasGlobalColorTable}");
             BitsPerColorChannel = (byte)(((flags >> 4) & 0x7) + 1);
             IsGlobalColorTableSorted = ((flags >> 3) & 0x1) != 0;
             GlobalColorTableSize = (int)Math.Pow(2, (flags & 0x7) + 1);
-            // Godot.GD.Print($"Global colour size? {GlobalColorTableSize}");
             BackgroundColorIndex = reader.ReadByte();
             var rawAspectRatio = reader.ReadByte();
             if (rawAspectRatio == 0)
@@ -86,6 +84,7 @@ public class GifDecoder
         private byte[] _colors;
         private byte[] _pixelIndices;
         private int _transparentIndex;
+        private readonly bool _interlaced;
 
         public ImageData(BinaryReader reader, byte[] globalColors, int transparentIndex)
         {
@@ -95,7 +94,7 @@ public class GifDecoder
             var height = reader.ReadUInt16();
             var flags = reader.ReadByte();
             var hasLocalColorTable = ((flags >> 7) & 0x1) != 0;
-            var interlaced = ((flags >> 6) & 0x1) != 0; // See appendix E for interlacing
+            _interlaced = ((flags >> 6) & 0x1) != 0; // See appendix E for interlacing
             var isLocalColorTableSorted = ((flags >> 5) & 0x1) != 0;
             var sizeOfLocalColorTable = (byte)Math.Pow(2, (flags & 0x7) + 1);
             byte[] colors;
@@ -140,7 +139,6 @@ public class GifDecoder
                 compressedBytes.AddRange(bytes);
                 blockSize = reader.ReadByte();
             }
-            // Godot.GD.Print($"End of image data: {reader.BaseStream.Position}");
 
             using MemoryStream compressedStream = new(compressedBytes.ToArray());
             using BinaryReader compressedReader = new(compressedStream, Encoding.UTF8, false);
@@ -180,7 +178,6 @@ public class GifDecoder
                 }
                 else if (code == endCode)
                 {
-                    // Godot.GD.Print($"CompressedBytesLeft: {compressedReader.BaseStream.Length - compressedReader.BaseStream.Position}");
                     break;
                 }
                 else if (code < codeCount)
@@ -256,17 +253,49 @@ public class GifDecoder
         {
             var bytesIdx = 0;
             var bytes = new byte[Width * Height * 4];
+
+            void WritePixelBytes(int bytesOffset, int colorIndex)
+            {
+                bytes[bytesOffset] = _colors[colorIndex * 3];
+                bytes[bytesOffset + 1] = _colors[colorIndex * 3 + 1];
+                bytes[bytesOffset + 2] = _colors[colorIndex * 3 + 2];
+                bytes[bytesOffset + 3] = (byte)((colorIndex == _transparentIndex) ? 0 : 255);
+            }
+
+            if (!_interlaced)
+            {
                 foreach (var colorIndex in _pixelIndices)
                 {
-                bytes[bytesIdx++] = _colors[colorIndex * 3];
+                    WritePixelBytes(bytesIdx, colorIndex);
-                bytes[bytesIdx++] = _colors[colorIndex * 3 + 1];
+                    bytesIdx += 4;
-                bytes[bytesIdx++] = _colors[colorIndex * 3 + 2];
-                // Fuck you LGS hardcoding the transparent index suck my balls
-                // bytes[bytesIdx++] = (byte)((colorIndex == _transparentIndex) ? 0 : 255);
-                bytes[bytesIdx++] = (byte)((colorIndex == 0) ? 0 : 255);
                 }
                 return bytes;
             }
+
+            var pass = 0;
+            var inc = 8;
+            var y = 0;
+            var indicesOffset = 0;
+            var bytesPerRow = Width * 4;
+            for (var i = 0; i < Height; i++)
+            {
+                bytesIdx = y * bytesPerRow;
+                for (var x = 0; x < Width; x++)
+                {
+                    WritePixelBytes(bytesIdx + x * 4, _pixelIndices[indicesOffset++]);
+                }
+
+                y += inc;
+                if (y >= Height)
+                {
+                    pass += 1;
+                    y = (int)(8 / Math.Pow(2, pass));
+                    inc = y * 2;
+                }
+            }
+
+            return bytes;
+        }
     }
 
     Header _header;
@@ -280,15 +309,12 @@ public class GifDecoder
             throw new FileNotFoundException();
         }
 
-        // Godot.GD.Print($"Decoding image at: {path}");
-
         using MemoryStream stream = new(File.ReadAllBytes(path));
         using BinaryReader reader = new(stream, Encoding.UTF8, false);
 
         _header = new Header(reader);
         _globalColors = ReadColorTable(reader, _header.HasGlobalColorTable ? _header.GlobalColorTableSize : 0);
         var images = new List<ImageData>();
-        var transparentIndex = -1;
         while (true)
         {
             var id = reader.ReadByte();
@@ -296,22 +322,18 @@ public class GifDecoder
             switch (id)
             {
                 case 0x2C: // Image
-                    // Godot.GD.Print("Adding new image!!");
+                    images.Add(new ImageData(reader, _globalColors, 0));
-                    images.Add(new ImageData(reader, _globalColors, transparentIndex));
-                    transparentIndex = -1;
                     break;
                 case 0x21: // Extension
-                    var extId = reader.ReadByte();
+                    // We don't need to actually handle any extensions. The only one that's
-                    if (extId == 0xF9)
+                    // potentially relevant is GraphicsControl, but Dark uses a hardcoded
+                    // transparency palette index and doesn't use multi-frame GIFs with timing.
+                    reader.ReadByte();
+                    var blockSize = reader.ReadByte();
+                    while (blockSize != 0)
                     {
-                        var graphicsControl = new GraphicsControl(reader);
+                        reader.ReadBytes(blockSize);
-                        transparentIndex = graphicsControl.TransparencyIndex;
+                        blockSize = reader.ReadByte();
-                        // Godot.GD.Print($"We set the transparent index: {transparentIndex} for {path}");
-                    }
-                    else
-                    {
-                        // We don't support Comment (0xFE), Text (0x01), or Application (0xFF) extensions
-                        throw new InvalidDataException($"Unknown or unsupported extension identifier in GIF file: {extId}");
                     }
                     break;
                 case 0x3B: