Example #1
0
        internal static DwgImageData Parse(BitReader reader)
        {
            var imageData = new DwgImageData();

            reader.ValidateSentinel(StartSentinel);
            var overallSize = reader.Read_RL();
            var startOffset = reader.Offset;
            var imageCount  = reader.Read_RC();

            var headerStart = 0;
            var headerSize  = 0;
            var bmpStart    = 0;
            var bmpSize     = 0;
            var wmfStart    = 0;
            var wmfSize     = 0;

            for (int i = 0; i < imageCount; i++)
            {
                var code  = reader.Read_RC();
                var start = reader.Read_RL();
                var size  = reader.Read_RL();

                switch (code)
                {
                case 1:
                    headerStart = start;
                    headerSize  = size;
                    break;

                case 2:
                    bmpStart = start;
                    bmpSize  = size;
                    break;

                case 3:
                    wmfStart = start;
                    wmfSize  = size;
                    break;
                }
            }

            if (headerSize > 0)
            {
                if (reader.Offset != headerStart)
                {
                    throw new DwgReadException("Unexpected image data header start.");
                }

                imageData.HeaderData = reader.ReadBytes(headerSize);
            }

            if (bmpSize > 0)
            {
                if (reader.Offset != bmpStart)
                {
                    throw new DwgReadException("Unexpected BMP data start.");
                }

                imageData.BmpData = reader.ReadBytes(bmpSize);
            }

            if (wmfSize > 0)
            {
                if (reader.Offset != wmfStart)
                {
                    throw new DwgReadException("Unexpected WMF data start.");
                }
                imageData.WmfData = reader.ReadBytes(wmfSize);
            }

            var endOffset = reader.Offset;
            var readBytes = endOffset - startOffset;

            if (readBytes != overallSize)
            {
                throw new DwgReadException($"Invalid count of read image data bytes.  Expected: {overallSize}, Actual: {readBytes}");
            }

            reader.ValidateSentinel(EndSentinel);
            return(imageData);
        }