/// <summary>
/// Message handler for <see cref="DataMessage"/>
/// </summary>
/// <param name="msg">The incoming message.</param>
/// <param name="packet">The buffer containing the message.</param>
/// <param name="reader">The reader from which the message came.</param>
/// <returns><see cref="ErrorCode.UnsupportedFeature"/></returns>
/// <remarks>
/// At this level, the function is only supported for handling <see cref="Tes.Shapes.MultiShape"/> data packets.
/// Otherwise it returns an error code.
/// </remarks>
protected virtual Error HandleMessage(DataMessage msg, PacketBuffer packet, BinaryReader reader)
{
// Retrieve the target shape.
ShapeCache cache = (msg.ObjectID == 0) ? _transientCache : _shapeCache;
int shapeIndex = (msg.ObjectID == 0) ? _lastTransientIndex : cache.GetShapeIndex(msg.ObjectID);
if (shapeIndex < 0)
{
return(new Error(ErrorCode.InvalidObjectID, msg.ObjectID));
}
// Check this is is a multi-shape.
CreateMessage shape = cache.GetShapeByIndex(shapeIndex);
if ((shape.Flags & (ushort)ObjectFlag.MultiShape) == 0)
{
return(new Error(ErrorCode.UnsupportedFeature));
}
// Add to the multi-shape chain.
int multiShapeHead = cache.GetMultiShapeChainByIndex(shapeIndex);
// Read new multi-shape block.
uint blockItemCount = (uint)reader.ReadUInt16();
int initialHead = multiShapeHead;
Error error = ReadMultiShapeBlock(cache, shapeIndex, shape, packet, reader, blockItemCount, ref multiShapeHead);
// Set the new multi shape chain head (even on failure for better clean up).
if (multiShapeHead != -1)
{
cache.SetMultiShapeChainByIndex(shapeIndex, multiShapeHead);
}
if (error.Failed)
{
return(error);
}
return(new Error());
}
/// <summary>
/// Read <see cref="Tes.Shapes.MultiShape"/> block.
/// </summary>
/// <param name="parentShape">The shape data defining the root of the multi-shape</param>
/// <param name="packet">The buffer containing the message.</param>
/// <param name="reader">The reader from which the message came.</param>
/// <param name="blockItemCount">The number of child items to read.</param>
/// <param name="multiChainHead">The head of the multi-shape linked list/chain.</param>
/// <returns>An error code on failure.</returns>
/// <remarks>
/// The <paramref name="multiChainHead"/> is expected to mark the start of the child item linked list. This is -1
/// when starting the list. The value is updated to mark the new head item index.
/// </remarks>
protected Error ReadMultiShapeBlock(ShapeCache cache, int shapeIndex, CreateMessage parentShape,
PacketBuffer packet, BinaryReader reader,
uint blockItemCount, ref int multiChainHead)
{
Matrix4x4 parentTransform = Maths.Matrix4Ext.ToUnity(parentShape.Attributes.GetTransform());
CreateMessage multiShape = parentShape.Clone();
// Clear the multi-shape flag so these shapes are visualised.
multiShape.Flags &= (ushort)(~ObjectFlag.MultiShape);
multiShape.ObjectID = ShapeCache.MultiShapeID;
// Read each shape attributes.
for (uint i = 0; i < blockItemCount; ++i)
{
if (!multiShape.Attributes.Read(reader))
{
return(new Error(ErrorCode.MalformedMessage, parentShape.ObjectID));
}
multiChainHead = CreateShape(cache, multiShape, multiChainHead, parentTransform);
}
return(new Error());
}
/// <summary>
/// Called at end of <see cref="HandleMessage(DestroyMessage, PacketBuffer, BinaryReader)"/>
/// just prior to destroying the object. The object will still be destroyed.
/// </summary>
/// <param name="msg">The incoming message.</param>
/// <param name="packet">The buffer containing the message.</param>
/// <param name="reader">The reader from which the message came.</param>
/// <returns>An error code on failure.</returns>
/// <remarks>
/// Neither the <see cref="PacketBuffer"/> nor the <see cref="BinaryReader"/> are provided as destroy message are
/// not allowed to carry additional payloads.
/// </remarks>
protected virtual Error PostHandleMessage(DestroyMessage msg, ShapeCache cache, int shapeIndex)
{
return(new Error());
}
/// <summary>
/// Called at end of <see cref="HandleMessage(UpdateMessage, PacketBuffer, BinaryReader)"/>, only on success.
/// </summary>
/// <param name="shapeIndex">Index of the shape in the _shapeCache which is being updated.</param>
/// <param name="msg">The incoming message.</param>
/// <param name="packet">The buffer containing the message.</param>
/// <param name="reader">The reader from which the message came.</param>
/// <returns>An error code on failure.</returns>
protected virtual Error PostHandleMessage(UpdateMessage msg, PacketBuffer packet, BinaryReader reader,
ShapeCache cache, int shapeIndex)
{
return(new Error());
}
/// <summary>
/// Called after serialising the creation message for an object. This allows follow up
/// data messages to be serialised.
/// </summary>
/// <param name="packet"></param>
/// <param name="writer"></param>
/// <param name="cache"></param>
/// <param name="shapeIndex"></param>
/// <returns></returns>
protected virtual Error PostSerialiseCreateObject(PacketBuffer packet, BinaryWriter writer, ShapeCache cache,
int shapeIndex)
{
return(new Error());
}
/// <summary>
/// Serialises a list of objects to <paramref name="writer"/>
/// </summary>
/// <param name="writer">The writer to serialise to.</param>
/// <param name="objects">The object to write.</param>
/// <param name="processedCount">Number of objects processed.</param>
/// <returns>An error code on failure.</returns>
/// <remarks>
/// Default serialisation uses the following logic on each object:
/// <list type="bullet">
/// <item>Call <see cref="CreateSerialisationShape(ShapeCache, int, CreateMessage)"/> to
/// create a temporary shape to match the unity object</item>
/// <item>Call <see cref="Shapes.Shape.WriteCreate(PacketBuffer)"/> to generate the creation message
/// and serialise the packet.</item>
/// <item>For complex shapes, call <see cref="Shapes.Shape.WriteData(PacketBuffer, ref uint)"/> as required
/// and serialise the packets.</item>
/// </list>
///
/// Using the <see cref="Shapes.Shape"/> classes ensures serialisation is consistent with the server code
/// and reduces the code maintenance to one code path.
/// </remarks>
protected virtual Error SerialiseShapes(BinaryWriter writer, ShapeCache cache, ref uint processedCount)
{
// Serialise transient objects.
PacketBuffer packet = new PacketBuffer();
Error err;
Shapes.Shape tempShape = null;
List <Shapes.Shape> multiShapeList = new List <Shapes.Shape>();
uint dataMarker = 0;
int dataResult = 0;
Debug.Assert(tempShape != null && tempShape.RoutingID == RoutingID);
processedCount = 0;
foreach (int shapeIndex in cache.ShapeIndices)
{
tempShape = null;
++processedCount;
CreateMessage shapeData = cache.GetShapeByIndex(shapeIndex);
if ((shapeData.Flags & (ushort)ObjectFlag.MultiShape) != 0)
{
// Multi-shape. Follow the link.
multiShapeList.Clear();
int nextIndex = cache.GetMultiShapeChainByIndex(shapeIndex);
while (nextIndex != -1)
{
CreateMessage multiShapeData = cache.GetShapeByIndex(nextIndex);
tempShape = CreateSerialisationShape(cache, shapeIndex, multiShapeData);
tempShape.ID = shapeData.ObjectID;
if (tempShape != null)
{
// Successfully created the child. Add to the list.
multiShapeList.Add(tempShape);
}
else
{
Debug.LogError($"{Name} failed to create multi-shape entry");
}
nextIndex = cache.GetMultiShapeChainByIndex(nextIndex);
}
// Create the multi-shape
tempShape = new Shapes.MultiShape(multiShapeList.ToArray());
tempShape.ID = shapeData.ObjectID;
tempShape.Category = shapeData.Category;
tempShape.SetAttributes(shapeData.Attributes);
}
else if (shapeData.ObjectID != ShapeCache.MultiShapeID)
{
tempShape = CreateSerialisationShape(cache, shapeIndex, shapeData);
}
if (tempShape != null)
{
tempShape.WriteCreate(packet);
packet.FinalisePacket();
packet.ExportTo(writer);
if (tempShape.IsComplex)
{
dataResult = 1;
dataMarker = 0;
while (dataResult > 0)
{
dataResult = tempShape.WriteData(packet, ref dataMarker);
packet.FinalisePacket();
packet.ExportTo(writer);
}
if (dataResult < 0)
{
return(new Error(ErrorCode.SerialisationFailure));
}
// Post serialisation extensions.
err = PostSerialiseCreateObject(packet, writer, cache, shapeIndex);
if (err.Failed)
{
return(err);
}
}
}
else if (shapeData.ObjectID != ShapeCache.MultiShapeID)
{
return(new Error(ErrorCode.SerialisationFailure));
}
}
return(new Error());
}
/// <summary>
/// Create a dummy shape object used to generate serialisation messages.
/// </summary>
/// <param name="cache">The cache in which the shape data reside</param>
/// <param name="shapeIndex">The index of the shape in <paramref name="cache"/>.
/// <param name="shape">Creation message for the shape.</param>
/// <returns>A shape instance suitable for configuring to generate serialisation messages.</returns>
/// <remarks>
/// Base classes should implement this method to return an instance of the appropriate
/// <see cref="Shapes.Shape"/> derivation. For example, the <see cref="Shape3D.SphereHandler"/>
/// should return a <see cref="Shapes.Sphere"/> object. See
/// <see cref="SerialiseShapes(BinaryWriter, ShapeCache, ref uint)"/> for further
/// details.
/// </remarks>
protected virtual Shapes.Shape CreateSerialisationShape(ShapeCache cache, int shapeIndex, CreateMessage shape)
{
return(new Shapes.Shape(RoutingID, shape));
}