public static FrameSectionPackage Deserialize(byte[] buffer, int startIndex)
{
FrameSectionPackage package = new FrameSectionPackage();
//Header
package.FrameSequenceIndex = BitConverter.ToInt32(buffer, startIndex);
package.Index = BitConverter.ToInt32(buffer, startIndex + 4);
int numberOfPixelInstructions = BitConverter.ToInt32(buffer, startIndex + 8);
//Content
package.pixelInstructions = new List <PixelInstruction>(numberOfPixelInstructions);
int pixelInstructionsStartIndex = startIndex + 12;
for (int i = 0; i < numberOfPixelInstructions; i++)
{
package.pixelInstructions.Add(PixelInstructionProtocol.Deserialize(buffer, pixelInstructionsStartIndex + i * PixelInstructionProtocol.BYTES_NEEDED));
}
if (package.pixelInstructions.Count != numberOfPixelInstructions)
{
throw new System.Net.ProtocolViolationException(
$"Failed to deserialize FrameSectionPackage, the number of pixelInstructions incorrect (exp. {numberOfPixelInstructions}, rec. {package.pixelInstructions.Count})");
}
return(package);
}
public static byte[][] SerializeFrame(FrameWithoutDelta frame, int maxSizePerPackage)
{
int bytesNeeded = HEADER_BYTES_NEEDED + frame.Items.Length * PixelInstructionProtocol.BYTES_NEEDED;
byte[][] packages;
if (bytesNeeded <= maxSizePerPackage)
{
// The frame is small enough to fit in a single packet.
// No FrameSectionPackage is needed.
packages = new byte[1][];
packages[0] = new byte[bytesNeeded];
BitConverter.GetBytes(frame.Index).CopyTo(packages[0], 0); // Sequence index
BitConverter.GetBytes(frame.TimeStampRelative).CopyTo(packages[0], 4); // TimeStamp (relative)
BitConverter.GetBytes(frame.Count).CopyTo(packages[0], 8); // Number of PixelInstructions
BitConverter.GetBytes(false).CopyTo(packages[0], 12); // Has FrameSections
for (int i = 0; i < frame.Count; i++)
{
int bufferStartIndex = HEADER_BYTES_NEEDED + i * PixelInstructionProtocol.BYTES_NEEDED;
PixelInstructionProtocol.Serialize(frame[i], packages[0], bufferStartIndex);
}
return(packages);
}
// This frame is too big to send as one packet.
// Create multiple packages with the help of FrameSectionPackage
// First, calculate the inital package
int headerBytesNeeded = HEADER_BYTES_NEEDED + FrameSectionProtocol.HEADER_BYTES_NEEDED;
int instructionsInFirstSection = (maxSizePerPackage - headerBytesNeeded) / PixelInstructionProtocol.BYTES_NEEDED;
// Second, calculate how many FrameSections are needed
int instructionsThatFitInOtherSections = (maxSizePerPackage - FrameSectionProtocol.HEADER_BYTES_NEEDED) / PixelInstructionProtocol.BYTES_NEEDED;
int frameSectionsNeeded = (int)Math.Ceiling((double)(frame.Count - instructionsInFirstSection) / instructionsThatFitInOtherSections) + 1; // +1 for the first section
packages = new byte[frameSectionsNeeded][];
// Third, create the Frame header and its first section
packages[0] = new byte[headerBytesNeeded + instructionsInFirstSection * PixelInstructionProtocol.BYTES_NEEDED];
BitConverter.GetBytes(frame.Index).CopyTo(packages[0], 0); // Sequence index
BitConverter.GetBytes(frame.TimeStampRelative).CopyTo(packages[0], 4); // TimeStamp (relative)
BitConverter.GetBytes(frameSectionsNeeded).CopyTo(packages[0], 8); // Number of FrameSets
BitConverter.GetBytes(true).CopyTo(packages[0], 12); // Has FrameSections
CreateFrameSection(packages[0], 13, frame, frame.Index, 0, 0, instructionsInFirstSection);
// Lastely, create the other frame sections. A new byte array (package) for each FrameSection.
for (int i = 0; i < frameSectionsNeeded - 1; i++)
{
int instructionStartIndex = instructionsInFirstSection + i * instructionsThatFitInOtherSections;
int instructionsInThisSection = Math.Min(instructionsThatFitInOtherSections, frame.Count - instructionStartIndex);
packages[i + 1] = new byte[FrameSectionProtocol.HEADER_BYTES_NEEDED + PixelInstructionProtocol.BYTES_NEEDED * instructionsInThisSection];
CreateFrameSection(packages[i + 1], 0, frame, frame.Index, i + 1, instructionStartIndex, instructionsInThisSection);
}
return(packages);
}
public const int HEADER_BYTES_NEEDED = sizeof(int) + sizeof(int) + sizeof(int); // frameSequenceIndex + Index + number of pixelinstructions;
public static byte[] Serialize(FrameSectionPackage package, byte[] buffer, int startIndex)
{
BitConverter.GetBytes(package.FrameSequenceIndex).CopyTo(buffer, startIndex);
BitConverter.GetBytes(package.Index).CopyTo(buffer, startIndex + 4);
BitConverter.GetBytes(package.pixelInstructions.Count).CopyTo(buffer, startIndex + 8);
int pixelInstructionsStartIndex = startIndex + 12;
for (int i = 0; i < package.pixelInstructions.Count; i++)
{
PixelInstructionProtocol.Serialize(package.pixelInstructions[i], buffer, pixelInstructionsStartIndex + i * PixelInstructionProtocol.BYTES_NEEDED);
}
return(buffer);
}
/// <summary>
/// Deserialize a package
/// </summary>
/// <param name="buffer"></param>
/// <returns>True if the frame has been deserialized, False if not all packages have been received.</returns>
public bool TryDeserialize(byte[] bytes, out FrameWithoutDelta frame)
{
frame = null;
if (_frameSectionPackages == null)
{
// First package.
// Read Frame header
int startIndex = 0;
_frameIndex = BitConverter.ToInt32(bytes, startIndex);
_timeStampRelative = BitConverter.ToInt32(bytes, startIndex += 4);
int itemCount = BitConverter.ToInt32(bytes, startIndex += 4);
bool hasFrameSections = BitConverter.ToBoolean(bytes, startIndex += 4);
startIndex += 1;
if (hasFrameSections)
{
_frameSectionPackages = new FrameSectionPackage[itemCount];
_frameSectionsReceived = new bool[itemCount];
_frameSectionsReceived[0] = true;
// The rest of the package is a FrameSection
_frameSectionPackages[0] = FrameSectionProtocol.Deserialize(bytes, startIndex);
return(false);
}
else
{
frame = new FrameWithoutDelta(_frameIndex, _timeStampRelative, itemCount);
// The rest of the package contains PixelInstructions
for (int i = 0; i < itemCount; i++)
{
int instructionStartIndex = startIndex + i * PixelInstructionProtocol.BYTES_NEEDED;
frame[i] = PixelInstructionProtocol.Deserialize(bytes, instructionStartIndex);
}
return(true);
}
}
else
{
// Subsequent package. Always starts with a FrameSection.
FrameSectionPackage package = FrameSectionProtocol.Deserialize(bytes, 0);
if (package.FrameSequenceIndex != _frameIndex)
{
throw new System.Net.ProtocolViolationException(
$"The frameIndex of the frameSection does not match with the Frame's index. Expected :{_frameIndex}, Received: {package.FrameSequenceIndex}");
}
_frameSectionPackages[package.Index] = package;
_frameSectionsReceived[package.Index] = true;
if (_frameSectionsReceived.All(x => x))
{
// TODO add totalNumberOfPixelInstructions to frame header
int totalPixelInstructions = _frameSectionPackages.Sum(x => x.NumberOfPixelInstructions);
frame = new FrameWithoutDelta(_frameIndex, _timeStampRelative, totalPixelInstructions);
int index = 0;
for (int i = 0; i < _frameSectionPackages.Length; i++)
{
for (int j = 0; j < _frameSectionPackages[i].NumberOfPixelInstructions; j++)
{
frame[index++] = _frameSectionPackages[i].pixelInstructions[j];
}
}
return(true);
}
return(false);
}
}
