From 6ba2a83bbe0c94aa5efad2f7b25c5b6118e81666 Mon Sep 17 00:00:00 2001
From: Ken Cooke <ken@highfidelity.io>
Date: Sun, 29 Oct 2017 10:47:56 -0700
Subject: [PATCH] Send and receive Avatar MASTER Gain packets, signaled using
 null nodeID. Packet protocol change is not needed (existing audio-mixer will
 ignore).

---
 .../src/audio/AudioMixerClientData.cpp              | 10 ++++++++--
 libraries/networking/src/NodeList.cpp               | 13 +++++++++----
 .../script-engine/src/UsersScriptingInterface.h     |  4 ++--
 3 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/assignment-client/src/audio/AudioMixerClientData.cpp b/assignment-client/src/audio/AudioMixerClientData.cpp
index 9bba9c7f30..59bc878cba 100644
--- a/assignment-client/src/audio/AudioMixerClientData.cpp
+++ b/assignment-client/src/audio/AudioMixerClientData.cpp
@@ -189,8 +189,14 @@ void AudioMixerClientData::parsePerAvatarGainSet(ReceivedMessage& message, const
     uint8_t packedGain;
     message.readPrimitive(&packedGain);
     float gain = unpackFloatGainFromByte(packedGain);
-    hrtfForStream(avatarUuid, QUuid()).setGainAdjustment(gain);
-    qDebug() << "Setting gain adjustment for hrtf[" << uuid << "][" << avatarUuid << "] to " << gain;
+
+    if (avatarUuid.isNull()) {
+        // FIXME: change master gain, and reset hrtf gains for all active streams
+        qDebug() << "Setting MASTER avatar gain for [" << uuid << "] to " << gain;
+    } else {
+        hrtfForStream(avatarUuid, QUuid()).setGainAdjustment(gain);
+        qDebug() << "Setting avatar gain adjustment for hrtf[" << uuid << "][" << avatarUuid << "] to " << gain;
+    }
 }
 
 void AudioMixerClientData::parseNodeIgnoreRequest(QSharedPointer<ReceivedMessage> message, const SharedNodePointer& node) {
diff --git a/libraries/networking/src/NodeList.cpp b/libraries/networking/src/NodeList.cpp
index 71128c5ff0..04699d8ad1 100644
--- a/libraries/networking/src/NodeList.cpp
+++ b/libraries/networking/src/NodeList.cpp
@@ -979,8 +979,8 @@ void NodeList::maybeSendIgnoreSetToNode(SharedNodePointer newNode) {
 }
 
 void NodeList::setAvatarGain(const QUuid& nodeID, float gain) {
-    // cannot set gain of yourself or nobody
-    if (!nodeID.isNull() && _sessionUUID != nodeID) {
+    // cannot set gain of yourself
+    if (_sessionUUID != nodeID) {
         auto audioMixer = soloNodeOfType(NodeType::AudioMixer);
         if (audioMixer) {
             // setup the packet
@@ -988,10 +988,15 @@ void NodeList::setAvatarGain(const QUuid& nodeID, float gain) {
 
             // write the node ID to the packet
             setAvatarGainPacket->write(nodeID.toRfc4122());
+
             // We need to convert the gain in dB (from the script) to an amplitude before packing it.
             setAvatarGainPacket->writePrimitive(packFloatGainToByte(fastExp2f(gain / 6.0206f)));
 
-            qCDebug(networking) << "Sending Set Avatar Gain packet UUID: " << uuidStringWithoutCurlyBraces(nodeID) << "Gain:" << gain;
+            if (nodeID.isNull()) {
+                qCDebug(networking) << "Sending Set Avatar MASTER Gain packet with Gain:" << gain;
+            } else {
+                qCDebug(networking) << "Sending Set Avatar Gain packet with UUID: " << uuidStringWithoutCurlyBraces(nodeID) << "Gain:" << gain;
+            }
 
             sendPacket(std::move(setAvatarGainPacket), *audioMixer);
             QWriteLocker{ &_avatarGainMapLock };
@@ -1001,7 +1006,7 @@ void NodeList::setAvatarGain(const QUuid& nodeID, float gain) {
             qWarning() << "Couldn't find audio mixer to send set gain request";
         }
     } else {
-        qWarning() << "NodeList::setAvatarGain called with an invalid ID or an ID which matches the current session ID:" << nodeID;
+        qWarning() << "NodeList::setAvatarGain called with an ID which matches the current session ID:" << nodeID;
     }
 }
 
diff --git a/libraries/script-engine/src/UsersScriptingInterface.h b/libraries/script-engine/src/UsersScriptingInterface.h
index acaa92d9c8..2d33bbca14 100644
--- a/libraries/script-engine/src/UsersScriptingInterface.h
+++ b/libraries/script-engine/src/UsersScriptingInterface.h
@@ -65,7 +65,7 @@ public slots:
     * Sets an avatar's gain for you and you only.
     * Units are Decibels (dB)
     * @function Users.setAvatarGain
-    * @param {nodeID} nodeID The node or session ID of the user whose gain you want to modify.
+    * @param {nodeID} nodeID The node or session ID of the user whose gain you want to modify, or null to set the master gain.
     * @param {float} gain The gain of the avatar you'd like to set. Units are dB.
     */
     void setAvatarGain(const QUuid& nodeID, float gain);
@@ -73,7 +73,7 @@ public slots:
     /**jsdoc
     * Gets an avatar's gain for you and you only.
     * @function Users.getAvatarGain
-    * @param {nodeID} nodeID The node or session ID of the user whose gain you want to get.
+    * @param {nodeID} nodeID The node or session ID of the user whose gain you want to get, or null to get the master gain.
     * @return {float} gain (in dB)
     */
     float getAvatarGain(const QUuid& nodeID);