Ejemplo n.º 1
0
        public void Save(PsdBinaryWriter writer, Boolean globalLayerInfo,
                         Boolean isLargeDocument)
        {
            Util.DebugMessage(writer.BaseStream, "Save, Begin, LayerInfo, {0}, {1}",
                              Signature, Key);

            writer.WriteAsciiChars(Signature);
            writer.WriteAsciiChars(Key);

            var startPosition = writer.BaseStream.Position;

            using (var lengthWriter = new PsdBlockLengthWriter(writer,
                                                               LayerInfoUtil.HasLongLength(Key, isLargeDocument)))
            {
                // Depending on the key, the length may be unpadded, 2-padded, or
                // 4-padded.  Thus, it is up to each implementation of WriteData to
                // pad the length correctly.
                WriteData(writer);
            }

            // Data for global layer info is always padded to a multiple of 4,
            // even if this causes the stated length to be incorrect.
            if (globalLayerInfo)
            {
                writer.WritePadding(startPosition, 4);
            }

            Util.DebugMessage(writer.BaseStream, "Save, End, LayerInfo, {0}, {1}",
                              Signature, Key);
        }
Ejemplo n.º 2
0
        /// <summary>
        /// Loads the next LayerInfo record.
        /// </summary>
        /// <param name="reader">The file reader</param>
        /// <param name="psdFile">The PSD file.</param>
        /// <param name="globalLayerInfo">True if the LayerInfo record is being
        ///   loaded from the end of the Layer and Mask Information section;
        ///   false if it is being loaded from the end of a Layer record.</param>
        public static LayerInfo Load(PsdBinaryReader reader, PsdFile psdFile,
                                     Boolean globalLayerInfo)
        {
            Util.DebugMessage(reader.BaseStream, "Load, Begin, LayerInfo");

            // Some keys use a signature of 8B64, but the identity of these keys
            // is undocumented.  We will therefore accept either signature.
            var signature = reader.ReadAsciiChars(4);

            if ((signature != "8BIM") && (signature != "8B64"))
            {
                throw new PsdInvalidException(
                          $"{nameof(LayerInfo)} signature invalid, must be 8BIM or 8B64.");
            }

            var key           = reader.ReadAsciiChars(4);
            var hasLongLength = LayerInfoUtil.HasLongLength(key, psdFile.IsLargeDocument);
            var length        = hasLongLength
        ? reader.ReadInt64()
        : reader.ReadInt32();
            var startPosition = reader.BaseStream.Position;

            LayerInfo result;

            switch (key)
            {
            case "Layr":
            case "Lr16":
            case "Lr32":
                result = new InfoLayers(reader, psdFile, key, length);
                break;

            case "lsct":
            case "lsdk":
                result = new LayerSectionInfo(reader, key, (Int32)length);
                break;

            case "luni":
                result = new LayerUnicodeName(reader);
                break;

            default:
                result = new RawLayerInfo(reader, signature, key, length);
                break;
            }

            // May have additional padding applied.
            var endPosition = startPosition + length;

            if (reader.BaseStream.Position < endPosition)
            {
                reader.BaseStream.Position = endPosition;
            }

            // Documentation states that the length is even-padded.  Actually:
            //   1. Most keys have 4-padded lengths.
            //   2. However, some keys (LMsk) have even-padded lengths.
            //   3. Other keys (Txt2, Lr16, Lr32) have unpadded lengths.
            //
            // Photoshop writes data that is always 4-padded, even when the stated
            // length is not a multiple of 4.  The length mismatch seems to occur
            // only on global layer info.  We do not read extra padding in other
            // cases because third-party programs are likely to follow the spec.

            if (globalLayerInfo)
            {
                reader.ReadPadding(startPosition, 4);
            }

            Util.DebugMessage(reader.BaseStream, "Load, End, LayerInfo, {0}, {1}",
                              result.Signature, result.Key);
            return(result);
        }