Use congestion control on server.

assignment-client/src/metavoxels/MetavoxelServer.cpp

@@ -109,10 +109,7 @@ void MetavoxelSession::update() {
     }
     // if we're sending a reliable delta, wait until it's acknowledged
     if (_reliableDeltaChannel) {
-        Bitstream& out = _sequencer.startPacket();
+        sendPacketGroup();
-        MetavoxelDeltaPendingMessage msg = { _reliableDeltaID };
-        out << QVariant::fromValue(msg);
-        _sequencer.endPacket();
         return;
     }
     Bitstream& out = _sequencer.startPacket();
@@ -143,6 +140,9 @@ void MetavoxelSession::update() {
     } else {
         _sequencer.endPacket();
     }
+    
+    // perhaps send additional packets to fill out the group
+    sendPacketGroup(1);   
 }
 
 void MetavoxelSession::handleMessage(const QVariant& message, Bitstream& in) {
@@ -179,3 +179,17 @@ void MetavoxelSession::checkReliableDeltaReceived() {
     _reliableDeltaData = MetavoxelData();
     _reliableDeltaChannel = NULL;
 }
+
+void MetavoxelSession::sendPacketGroup(int alreadySent) {
+    int additionalPackets = _sequencer.notePacketGroup() - alreadySent;
+    for (int i = 0; i < additionalPackets; i++) {
+        Bitstream& out = _sequencer.startPacket();
+        if (_reliableDeltaChannel) {
+            MetavoxelDeltaPendingMessage msg = { _reliableDeltaID };
+            out << QVariant::fromValue(msg);
+        } else {
+            out << QVariant();
+        }
+        _sequencer.endPacket();
+    }
+}

assignment-client/src/metavoxels/MetavoxelServer.h

@@ -74,6 +74,8 @@ private slots:
     
 private:
     
+    void sendPacketGroup(int alreadySent = 0);
+    
     MetavoxelServer* _server;
     
     MetavoxelLOD _lod;

libraries/metavoxels/src/DatagramSequencer.cpp

@@ -79,7 +79,7 @@ ReliableChannel* DatagramSequencer::getReliableInputChannel(int index) {
     return channel;
 }
 
-int DatagramSequencer::startPacketGroup(int desiredPackets) {
+int DatagramSequencer::notePacketGroup(int desiredPackets) {
     // figure out how much data we have enqueued and increase the number of packets desired
     int totalAvailable = 0;
     foreach (ReliableChannel* channel, _reliableOutputChannels) {

libraries/metavoxels/src/DatagramSequencer.h

@@ -108,10 +108,10 @@ public:
     /// Returns the intput channel at the specified index, creating it if necessary.
     ReliableChannel* getReliableInputChannel(int index = 0);
     
-    /// Starts a packet group.
+    /// Notes that we're sending a group of packets.
     /// \param desiredPackets the number of packets we'd like to write in the group
     /// \return the number of packets to write in the group
-    int startPacketGroup(int desiredPackets = 1);
+    int notePacketGroup(int desiredPackets = 1);
     
     /// Starts a new packet for transmission.
     /// \return a reference to the Bitstream to use for writing to the packet

tests/metavoxels/src/MetavoxelTests.cpp

@@ -859,7 +859,7 @@ bool TestEndpoint::simulate(int iterationNumber) {
             bytesReceived += datagram.size();
             _remainingPipelineCapacity += datagram.size();
         }
-        int packetCount = _sequencer.startPacketGroup();
+        int packetCount = _sequencer.notePacketGroup();
         groupsSent++;
         maxPacketsPerGroup = qMax(maxPacketsPerGroup, packetCount);
         for (int i = 0; i < packetCount; i++) {