diff --git a/assignment-client/src/audio/AudioMixer.cpp b/assignment-client/src/audio/AudioMixer.cpp
index 0f51bd00b1..03bb32cd53 100644
--- a/assignment-client/src/audio/AudioMixer.cpp
+++ b/assignment-client/src/audio/AudioMixer.cpp
@@ -339,21 +339,18 @@ bool AudioMixer::prepareMixForListeningNode(Node* node) {
         }
     });
 
-    int nonZeroSamples = 0;
+    // use the per listner AudioLimiter to render the mixed data...
+    listenerNodeData->audioLimiter.render(_mixedSamples, _clampedSamples, AudioConstants::NETWORK_FRAME_SAMPLES_PER_CHANNEL);
 
-    // enumerate the mixed samples and clamp any samples outside the min/max
-    // also check if we ended up with a silent frame
+    // check for silent audio after the peak limitor has converted the samples
+    bool hasAudio = false;
     for (int i = 0; i < AudioConstants::NETWORK_FRAME_SAMPLES_STEREO; ++i) {
-
-        _clampedSamples[i] = int16_t(glm::clamp(int(_mixedSamples[i] * AudioConstants::MAX_SAMPLE_VALUE),
-                                                AudioConstants::MIN_SAMPLE_VALUE,
-                                                AudioConstants::MAX_SAMPLE_VALUE));
-        if (_clampedSamples[i] != 0.0f) {
-            ++nonZeroSamples;
+        if (_clampedSamples[i] != 0) {
+            hasAudio = true;
+            break;
         }
     }
-
-    return (nonZeroSamples > 0);
+    return hasAudio;
 }
 
 void AudioMixer::sendAudioEnvironmentPacket(SharedNodePointer node) {
diff --git a/assignment-client/src/audio/AudioMixerClientData.cpp b/assignment-client/src/audio/AudioMixerClientData.cpp
index 93a51b1df2..20003ba10d 100644
--- a/assignment-client/src/audio/AudioMixerClientData.cpp
+++ b/assignment-client/src/audio/AudioMixerClientData.cpp
@@ -25,6 +25,7 @@
 
 AudioMixerClientData::AudioMixerClientData(const QUuid& nodeID) :
     NodeData(nodeID),
+    audioLimiter(AudioConstants::SAMPLE_RATE, AudioConstants::STEREO),
     _outgoingMixedAudioSequenceNumber(0),
     _downstreamAudioStreamStats()
 {
diff --git a/assignment-client/src/audio/AudioMixerClientData.h b/assignment-client/src/audio/AudioMixerClientData.h
index ff4143cf08..17274a1519 100644
--- a/assignment-client/src/audio/AudioMixerClientData.h
+++ b/assignment-client/src/audio/AudioMixerClientData.h
@@ -16,11 +16,13 @@
 
 #include <AABox.h>
 #include <AudioHRTF.h>
+#include <AudioLimiter.h>
 #include <UUIDHasher.h>
 
 #include "PositionalAudioStream.h"
 #include "AvatarAudioStream.h"
 
+
 class AudioMixerClientData : public NodeData {
     Q_OBJECT
 public:
@@ -61,6 +63,8 @@ public:
     // uses randomization to have the AudioMixer send a stats packet to this node around every second
     bool shouldSendStats(int frameNumber);
 
+    AudioLimiter audioLimiter;
+
 signals:
     void injectorStreamFinished(const QUuid& streamIdentifier);
 
diff --git a/domain-server/resources/describe-settings.json b/domain-server/resources/describe-settings.json
index 53d062d4bd..cac0d28e1e 100644
--- a/domain-server/resources/describe-settings.json
+++ b/domain-server/resources/describe-settings.json
@@ -111,7 +111,7 @@
         {
           "name": "maximum_user_capacity",
           "label": "Maximum User Capacity",
-          "help": "The limit on how many avatars can be connected at once.  0 means no limit.",
+          "help": "The limit on how many users can be connected at once (0 means no limit). Avatars connected from the same machine will not count towards this limit.",
           "placeholder": "0",
           "default": "0",
           "advanced": false
diff --git a/domain-server/src/DomainServer.cpp b/domain-server/src/DomainServer.cpp
index f6fbb3f470..052a7c0fec 100644
--- a/domain-server/src/DomainServer.cpp
+++ b/domain-server/src/DomainServer.cpp
@@ -715,9 +715,13 @@ void DomainServer::processListRequestPacket(QSharedPointer<ReceivedMessage> mess
 unsigned int DomainServer::countConnectedUsers() {
     unsigned int result = 0;
     auto nodeList = DependencyManager::get<LimitedNodeList>();
-    nodeList->eachNode([&](const SharedNodePointer& otherNode){
-        if (otherNode->getType() == NodeType::Agent) {
-            result++;
+    nodeList->eachNode([&](const SharedNodePointer& node){
+        // only count unassigned agents (i.e., users)
+        if (node->getType() == NodeType::Agent) {
+            auto nodeData = static_cast<DomainServerNodeData*>(node->getLinkedData());
+            if (nodeData && !nodeData->wasAssigned()) {
+                result++;
+            }
         }
     });
     return result;
diff --git a/interface/resources/qml/dialogs/FileDialog.qml b/interface/resources/qml/dialogs/FileDialog.qml
index 00a66c01cc..015a192185 100644
--- a/interface/resources/qml/dialogs/FileDialog.qml
+++ b/interface/resources/qml/dialogs/FileDialog.qml
@@ -26,10 +26,10 @@ import "fileDialog"
 ModalWindow {
     id: root
     resizable: true
-    implicitWidth: 640
-    implicitHeight: 480
+    implicitWidth: 480
+    implicitHeight: 360
 
-    minSize: Qt.vector2d(300, 240)
+    minSize: Qt.vector2d(360, 240)
     draggable: true
 
     HifiConstants { id: hifi }
@@ -79,6 +79,9 @@ ModalWindow {
         fileTableModel.folder = initialFolder;
 
         iconText = root.title !== "" ? hifi.glyphs.scriptUpload : "";
+
+        // Clear selection when click on external frame.
+        frameClicked.connect(function() { d.clearSelection(); });
     }
 
     Item {
@@ -87,6 +90,13 @@ ModalWindow {
         height: pane.height
         anchors.margins: 0
 
+        MouseArea {
+            // Clear selection when click on internal unused area.
+            anchors.fill: parent
+            drag.target: root
+            onClicked: d.clearSelection()
+        }
+
         Row {
             id: navControls
             anchors {
@@ -202,6 +212,8 @@ ModalWindow {
             function update() {
                 var row = fileTableView.currentRow;
 
+                openButton.text = root.selectDirectory && row === -1 ? "Choose" : "Open"
+
                 if (row === -1) {
                     return;
                 }
@@ -226,6 +238,12 @@ ModalWindow {
                 fileTableModel.folder = homeDestination;
                 return true;
             }
+
+            function clearSelection() {
+                fileTableView.selection.clear();
+                fileTableView.currentRow = -1;
+                update();
+            }
         }
 
         FolderListModel {
@@ -389,6 +407,8 @@ ModalWindow {
 
                     rows++;
                 }
+
+                d.clearSelection();
             }
         }
 
@@ -633,8 +653,15 @@ ModalWindow {
         Action {
             id: okAction
             text: root.saveDialog ? "Save" : (root.selectDirectory ? "Choose" : "Open")
-            enabled: currentSelection.text ? true : false
-            onTriggered: okActionTimer.start();
+            enabled: currentSelection.text || !root.selectDirectory && d.currentSelectionIsFolder ? true : false
+            onTriggered: {
+                if (!root.selectDirectory && !d.currentSelectionIsFolder
+                        || root.selectDirectory && fileTableView.currentRow === -1) {
+                    okActionTimer.start();
+                } else {
+                    fileTableView.navigateToCurrentRow();
+                }
+            }
         }
 
         Timer {
diff --git a/interface/resources/qml/windows-uit/ModalFrame.qml b/interface/resources/qml/windows-uit/ModalFrame.qml
index 44c0b6a456..211353b5f3 100644
--- a/interface/resources/qml/windows-uit/ModalFrame.qml
+++ b/interface/resources/qml/windows-uit/ModalFrame.qml
@@ -27,6 +27,8 @@ Frame {
         readonly property int frameMarginTop: hifi.dimensions.modalDialogMargin.y + (frameContent.hasTitle ? hifi.dimensions.modalDialogTitleHeight + 10 : 0)
         readonly property int frameMarginBottom: hifi.dimensions.modalDialogMargin.y
 
+        signal frameClicked();
+
         anchors {
             fill: parent
             topMargin: -frameMarginTop
@@ -47,6 +49,7 @@ Frame {
             anchors.fill: parent
             drag.target: window
             enabled: window.draggable
+            onClicked: window.frameClicked();
         }
 
         Item {
diff --git a/interface/resources/qml/windows-uit/ModalWindow.qml b/interface/resources/qml/windows-uit/ModalWindow.qml
index f429e98ac3..144165e4e1 100644
--- a/interface/resources/qml/windows-uit/ModalWindow.qml
+++ b/interface/resources/qml/windows-uit/ModalWindow.qml
@@ -22,5 +22,7 @@ Window {
     property int colorScheme: hifi.colorSchemes.light
     property bool draggable: false
 
+    signal frameClicked();
+
     anchors.centerIn: draggable ? undefined : parent
 }
diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index 48b418b93c..e789b7c508 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -994,7 +994,7 @@ Application::Application(int& argc, char** argv, QElapsedTimer& startupTimer) :
         if (_keyboardFocusedItem != entityItemID) {
             _keyboardFocusedItem = UNKNOWN_ENTITY_ID;
             auto properties = entityScriptingInterface->getEntityProperties(entityItemID);
-            if (EntityTypes::Web == properties.getType() && !properties.getLocked()) {
+            if (EntityTypes::Web == properties.getType() && !properties.getLocked() && properties.getVisible()) {
                 auto entity = entityScriptingInterface->getEntityTree()->findEntityByID(entityItemID);
                 RenderableWebEntityItem* webEntity = dynamic_cast<RenderableWebEntityItem*>(entity.get());
                 if (webEntity) {
@@ -1049,6 +1049,13 @@ Application::Application(int& argc, char** argv, QElapsedTimer& startupTimer) :
         }
     });
 
+    connect(this, &Application::aboutToQuit, [=]() {
+        _keyboardFocusedItem = UNKNOWN_ENTITY_ID;
+        if (_keyboardFocusHighlight) {
+            _keyboardFocusHighlight->setVisible(false);
+        }
+    });
+
     // Make sure we don't time out during slow operations at startup
     updateHeartbeat();
 
@@ -1503,7 +1510,13 @@ void Application::paintGL() {
     // FIXME not needed anymore?
     _offscreenContext->makeCurrent();
 
-    displayPlugin->beginFrameRender(_frameCount);
+    // If a display plugin loses it's underlying support, it 
+    // needs to be able to signal us to not use it
+    if (!displayPlugin->beginFrameRender(_frameCount)) {
+        _inPaint = false;
+        updateDisplayMode();
+        return;
+    }
 
     // update the avatar with a fresh HMD pose
     getMyAvatar()->updateFromHMDSensorMatrix(getHMDSensorPose());
@@ -5098,9 +5111,17 @@ void Application::updateDisplayMode() {
 
         foreach(auto displayPlugin, standard) {
             addDisplayPluginToMenu(displayPlugin, first);
+            auto displayPluginName = displayPlugin->getName();
             QObject::connect(displayPlugin.get(), &DisplayPlugin::recommendedFramebufferSizeChanged, [this](const QSize & size) {
                 resizeGL();
             });
+            QObject::connect(displayPlugin.get(), &DisplayPlugin::outputDeviceLost, [this, displayPluginName] {
+                PluginManager::getInstance()->disableDisplayPlugin(displayPluginName);
+                auto menu = Menu::getInstance();
+                if (menu->menuItemExists(MenuOption::OutputMenu, displayPluginName)) {
+                    menu->removeMenuItem(MenuOption::OutputMenu, displayPluginName);
+                }
+            });
             first = false;
         }
 
@@ -5116,6 +5137,10 @@ void Application::updateDisplayMode() {
     foreach(DisplayPluginPointer displayPlugin, PluginManager::getInstance()->getDisplayPlugins()) {
         QString name = displayPlugin->getName();
         QAction* action = menu->getActionForOption(name);
+        // Menu might have been removed if the display plugin lost
+        if (!action) {
+            continue;
+        }
         if (action->isChecked()) {
             newDisplayPlugin = displayPlugin;
             break;
diff --git a/interface/src/avatar/AvatarManager.cpp b/interface/src/avatar/AvatarManager.cpp
index ddadcb3909..68d2eca2c0 100644
--- a/interface/src/avatar/AvatarManager.cpp
+++ b/interface/src/avatar/AvatarManager.cpp
@@ -322,7 +322,7 @@ void AvatarManager::handleCollisionEvents(const CollisionEvents& collisionEvents
                 const auto characterController = myAvatar->getCharacterController();
                 const float avatarVelocityChange = (characterController ? glm::length(characterController->getVelocityChange()) : 0.0f);
                 const float velocityChange = glm::length(collision.velocityChange) + avatarVelocityChange;
-                const float MIN_AVATAR_COLLISION_ACCELERATION = 0.01f;
+                const float MIN_AVATAR_COLLISION_ACCELERATION = 2.4f; // walking speed
                 const bool isSound = (collision.type == CONTACT_EVENT_TYPE_START) && (velocityChange > MIN_AVATAR_COLLISION_ACCELERATION);
 
                 if (!isSound) {
@@ -330,14 +330,24 @@ void AvatarManager::handleCollisionEvents(const CollisionEvents& collisionEvents
                 }
                 // Your avatar sound is personal to you, so let's say the "mass" part of the kinetic energy is already accounted for.
                 const float energy = velocityChange * velocityChange;
-                const float COLLISION_ENERGY_AT_FULL_VOLUME = 0.5f;
+                const float COLLISION_ENERGY_AT_FULL_VOLUME = 10.0f;
                 const float energyFactorOfFull = fmin(1.0f, energy / COLLISION_ENERGY_AT_FULL_VOLUME);
 
                 // For general entity collisionSoundURL, playSound supports changing the pitch for the sound based on the size of the object,
                 // but most avatars are roughly the same size, so let's not be so fancy yet.
                 const float AVATAR_STRETCH_FACTOR = 1.0f;
 
-                AudioInjector::playSound(collisionSound, energyFactorOfFull, AVATAR_STRETCH_FACTOR, myAvatar->getPosition());
+
+                _collisionInjectors.remove_if([](QPointer<AudioInjector>& injector) {
+                    return !injector || injector->isFinished();
+                });
+
+                static const int MAX_INJECTOR_COUNT = 3;
+                if (_collisionInjectors.size() < MAX_INJECTOR_COUNT) {
+                    auto injector = AudioInjector::playSound(collisionSound, energyFactorOfFull, AVATAR_STRETCH_FACTOR,
+                                                             myAvatar->getPosition());
+                    _collisionInjectors.emplace_back(injector);
+                }
                 myAvatar->collisionWithEntity(collision);
                 return;
             }
diff --git a/interface/src/avatar/AvatarManager.h b/interface/src/avatar/AvatarManager.h
index 1cd295d69f..9be186301d 100644
--- a/interface/src/avatar/AvatarManager.h
+++ b/interface/src/avatar/AvatarManager.h
@@ -25,6 +25,7 @@
 #include "AvatarMotionState.h"
 
 class MyAvatar;
+class AudioInjector;
 
 class AvatarManager : public AvatarHashMap {
     Q_OBJECT
@@ -94,6 +95,8 @@ private:
 
     bool _shouldShowReceiveStats = false;
 
+    std::list<QPointer<AudioInjector>> _collisionInjectors;
+
     SetOfAvatarMotionStates _motionStatesThatMightUpdate;
     SetOfMotionStates _motionStatesToAddToPhysics;
     VectorOfMotionStates _motionStatesToRemoveFromPhysics;
diff --git a/libraries/audio/src/AudioConstants.h b/libraries/audio/src/AudioConstants.h
index 38fead87f1..dbbe434915 100644
--- a/libraries/audio/src/AudioConstants.h
+++ b/libraries/audio/src/AudioConstants.h
@@ -18,6 +18,9 @@
 
 namespace AudioConstants {
     const int SAMPLE_RATE = 24000;
+    const int MONO = 1;
+    const int STEREO = 2;
+
 
     typedef int16_t AudioSample;
 
diff --git a/libraries/entities-renderer/src/RenderableProceduralItemShader.h b/libraries/entities-renderer/src/RenderableProceduralItemShader.h
index 1afd3bc608..4762f619bf 100644
--- a/libraries/entities-renderer/src/RenderableProceduralItemShader.h
+++ b/libraries/entities-renderer/src/RenderableProceduralItemShader.h
@@ -25,24 +25,43 @@ layout(location = 2) out vec4 _fragColor2;
 
 // the alpha threshold
 uniform float alphaThreshold;
-uniform sampler2D normalFittingMap;
 
-vec3 bestFitNormal(vec3 normal) {
-    vec3 absNorm = abs(normal);
-    float maxNAbs = max(absNorm.z, max(absNorm.x, absNorm.y));
+vec2 signNotZero(vec2 v) {
+    return vec2((v.x >= 0.0) ? +1.0 : -1.0, (v.y >= 0.0) ? +1.0 : -1.0);
+}
 
-    vec2 texcoord = (absNorm.z < maxNAbs ? 
-                        (absNorm.y < maxNAbs ? absNorm.yz : absNorm.xz) :
-                        absNorm.xy);
-    texcoord = (texcoord.x < texcoord.y ? texcoord.yx : texcoord.xy);
-    texcoord.y /= texcoord.x;
-    vec3 cN = normal / maxNAbs;
-    float fittingScale = texture(normalFittingMap, texcoord).a;
-    cN *= fittingScale;
-    return (cN * 0.5 + 0.5);
+vec2 float32x3_to_oct(in vec3 v) {
+    vec2 p = v.xy * (1.0 / (abs(v.x) + abs(v.y) + abs(v.z)));
+    return ((v.z <= 0.0) ? ((1.0 - abs(p.yx)) * signNotZero(p)) : p);
 }
 
 
+vec3 oct_to_float32x3(in vec2 e) {
+    vec3 v = vec3(e.xy, 1.0 - abs(e.x) - abs(e.y));
+    if (v.z < 0) {
+        v.xy = (1.0 - abs(v.yx)) * signNotZero(v.xy);
+    }
+    return normalize(v);
+}
+
+vec3 snorm12x2_to_unorm8x3(vec2 f) {
+    vec2 u = vec2(round(clamp(f, -1.0, 1.0) * 2047.0 + 2047.0));
+    float t = floor(u.y / 256.0);
+
+    return floor(vec3(
+        u.x / 16.0,
+        fract(u.x / 16.0) * 256.0 + t,
+        u.y - t * 256.0
+        )) / 255.0;
+}
+
+vec2 unorm8x3_to_snorm12x2(vec3 u) {
+    u *= 255.0;
+    u.y *= (1.0 / 16.0);
+    vec2 s = vec2(  u.x * 16.0 + floor(u.y),
+                    fract(u.y) * (16.0 * 256.0) + u.z);
+    return clamp(s * (1.0 / 2047.0) - 1.0, vec2(-1.0), vec2(1.0));
+}
 
 float mod289(float x) {
     return x - floor(x * (1.0 / 289.0)) * 289.0; 
@@ -322,7 +341,7 @@ void main(void) {
     }
 
     vec4 diffuse = vec4(_color.rgb, alpha);
-    vec4 normal = vec4(normalize(bestFitNormal(_normal)), 0.5);
+    vec4 normal = vec4(packNormal(normalize(_normal)), 0.5);
 
     _fragColor0 = diffuse;
     _fragColor1 = normal;
@@ -355,7 +374,7 @@ void main(void) {
     float emissiveAmount = getProceduralColors(diffuse, specular, shininess);
 
     _fragColor0 = vec4(diffuse.rgb, 1.0);
-    _fragColor1 = vec4(bestFitNormal(normalize(_normal.xyz)), 1.0 - (emissiveAmount / 2.0));
+    _fragColor1 = vec4(packNormal(normalize(_normal.xyz)), 1.0 - (emissiveAmount / 2.0));
     _fragColor2 = vec4(specular, shininess / 128.0);
 }
 )SCRIBE";
diff --git a/libraries/entities-renderer/src/RenderableWebEntityItem.cpp b/libraries/entities-renderer/src/RenderableWebEntityItem.cpp
index f0244d0e3f..8298dbcec5 100644
--- a/libraries/entities-renderer/src/RenderableWebEntityItem.cpp
+++ b/libraries/entities-renderer/src/RenderableWebEntityItem.cpp
@@ -226,10 +226,15 @@ void RenderableWebEntityItem::setSourceUrl(const QString& value) {
 }
 
 void RenderableWebEntityItem::setProxyWindow(QWindow* proxyWindow) {
-    _webSurface->setProxyWindow(proxyWindow);
+    if (_webSurface) {
+        _webSurface->setProxyWindow(proxyWindow);
+    }
 }
 
 QObject* RenderableWebEntityItem::getEventHandler() {
+    if (!_webSurface) {
+        return nullptr;
+    }
     return _webSurface->getEventHandler();
 }
 
diff --git a/libraries/entities/src/EntityItem.cpp b/libraries/entities/src/EntityItem.cpp
index dc5fbf7d8e..64b6a2c655 100644
--- a/libraries/entities/src/EntityItem.cpp
+++ b/libraries/entities/src/EntityItem.cpp
@@ -687,15 +687,80 @@ int EntityItem::readEntityDataFromBuffer(const unsigned char* data, int bytesLef
         }
     }
     {   // When we own the simulation we don't accept updates to the entity's transform/velocities
-        // but since we're using macros below we have to temporarily modify overwriteLocalData.
-        bool oldOverwrite = overwriteLocalData;
-        overwriteLocalData = overwriteLocalData && !weOwnSimulation;
-        READ_ENTITY_PROPERTY(PROP_POSITION, glm::vec3, updatePositionFromNetwork);
-        READ_ENTITY_PROPERTY(PROP_ROTATION, glm::quat, updateRotationFromNetwork);
-        READ_ENTITY_PROPERTY(PROP_VELOCITY, glm::vec3, updateVelocityFromNetwork);
-        READ_ENTITY_PROPERTY(PROP_ANGULAR_VELOCITY, glm::vec3, updateAngularVelocityFromNetwork);
-        READ_ENTITY_PROPERTY(PROP_ACCELERATION, glm::vec3, setAcceleration);
-        overwriteLocalData = oldOverwrite;
+        // we also want to ignore any duplicate packets that have the same "recently updated" values
+        // as a packet we've already recieved. This is because we want multiple edits of the same 
+        // information to be idempotent, but if we applied new physics properties we'd resimulation
+        // with small differences in results.
+
+        // Because the regular streaming property "setters" only have access to the new value, we've
+        // made these lambdas that can access other details about the previous updates to suppress
+        // any duplicates.
+
+        // Note: duplicate packets are expected and not wrong. They may be sent for any number of 
+        // reasons and the contract is that the client handles them in an idempotent manner.
+        auto lastEdited = lastEditedFromBufferAdjusted;
+        auto customUpdatePositionFromNetwork = [this, lastEdited, overwriteLocalData, weOwnSimulation](glm::vec3 value){
+            bool simulationChanged = lastEdited > _lastUpdatedPositionTimestamp;
+            bool valueChanged = value != _lastUpdatedPositionValue;
+            bool shouldUpdate = overwriteLocalData && !weOwnSimulation && simulationChanged && valueChanged;
+            if (shouldUpdate) {
+                updatePositionFromNetwork(value);
+                _lastUpdatedPositionTimestamp = lastEdited;
+                _lastUpdatedPositionValue = value;
+            }
+        };
+
+        auto customUpdateRotationFromNetwork = [this, lastEdited, overwriteLocalData, weOwnSimulation](glm::quat value){
+            bool simulationChanged = lastEdited > _lastUpdatedRotationTimestamp;
+            bool valueChanged = value != _lastUpdatedRotationValue;
+            bool shouldUpdate = overwriteLocalData && !weOwnSimulation && simulationChanged && valueChanged;
+            if (shouldUpdate) {
+                updateRotationFromNetwork(value);
+                _lastUpdatedRotationTimestamp = lastEdited;
+                _lastUpdatedRotationValue = value;
+            }
+        };
+
+        auto customUpdateVelocityFromNetwork = [this, lastEdited, overwriteLocalData, weOwnSimulation](glm::vec3 value){
+            bool simulationChanged = lastEdited > _lastUpdatedVelocityTimestamp;
+            bool valueChanged = value != _lastUpdatedVelocityValue;
+            bool shouldUpdate = overwriteLocalData && !weOwnSimulation && simulationChanged && valueChanged;
+            if (shouldUpdate) {
+                updateVelocityFromNetwork(value);
+                _lastUpdatedVelocityTimestamp = lastEdited;
+                _lastUpdatedVelocityValue = value;
+            }
+        };
+
+        auto customUpdateAngularVelocityFromNetwork = [this, lastEdited, overwriteLocalData, weOwnSimulation](glm::vec3 value){
+            bool simulationChanged = lastEdited > _lastUpdatedAngularVelocityTimestamp;
+            bool valueChanged = value != _lastUpdatedAngularVelocityValue;
+            bool shouldUpdate = overwriteLocalData && !weOwnSimulation && simulationChanged && valueChanged;
+            if (shouldUpdate) {
+                updateAngularVelocityFromNetwork(value);
+                _lastUpdatedAngularVelocityTimestamp = lastEdited;
+                _lastUpdatedAngularVelocityValue = value;
+            }
+        };
+
+        auto customSetAcceleration = [this, lastEdited, overwriteLocalData, weOwnSimulation](glm::vec3 value){
+            bool simulationChanged = lastEdited > _lastUpdatedAccelerationTimestamp;
+            bool valueChanged = value != _lastUpdatedAccelerationValue;
+            bool shouldUpdate = overwriteLocalData && !weOwnSimulation && simulationChanged && valueChanged;
+            if (shouldUpdate) {
+                setAcceleration(value);
+                _lastUpdatedAccelerationTimestamp = lastEdited;
+                _lastUpdatedAccelerationValue = value;
+            }
+        };
+
+        READ_ENTITY_PROPERTY(PROP_POSITION, glm::vec3, customUpdatePositionFromNetwork);
+        READ_ENTITY_PROPERTY(PROP_ROTATION, glm::quat, customUpdateRotationFromNetwork);
+        READ_ENTITY_PROPERTY(PROP_VELOCITY, glm::vec3, customUpdateVelocityFromNetwork);
+        READ_ENTITY_PROPERTY(PROP_ANGULAR_VELOCITY, glm::vec3, customUpdateAngularVelocityFromNetwork);
+        READ_ENTITY_PROPERTY(PROP_ACCELERATION, glm::vec3, customSetAcceleration);
+
+
     }
 
     READ_ENTITY_PROPERTY(PROP_DIMENSIONS, glm::vec3, updateDimensions);
@@ -922,13 +987,11 @@ void EntityItem::simulate(const quint64& now) {
         qCDebug(entities) << "     ********** EntityItem::simulate() .... SETTING _lastSimulated=" << _lastSimulated;
     #endif
 
-    if (!hasActions()) {
-        if (!stepKinematicMotion(timeElapsed)) {
-            // this entity is no longer moving
-            // flag it to transition from KINEMATIC to STATIC
-            _dirtyFlags |= Simulation::DIRTY_MOTION_TYPE;
-            setAcceleration(Vectors::ZERO);
-        }
+    if (!stepKinematicMotion(timeElapsed)) {
+        // this entity is no longer moving
+        // flag it to transition from KINEMATIC to STATIC
+        _dirtyFlags |= Simulation::DIRTY_MOTION_TYPE;
+        setAcceleration(Vectors::ZERO);
     }
     _lastSimulated = now;
 }
diff --git a/libraries/entities/src/EntityItem.h b/libraries/entities/src/EntityItem.h
index 2c6dc9b74d..4a691462ab 100644
--- a/libraries/entities/src/EntityItem.h
+++ b/libraries/entities/src/EntityItem.h
@@ -550,6 +550,22 @@ protected:
 
     bool _clientOnly { false };
     QUuid _owningAvatarID;
+
+    // physics related changes from the network to suppress any duplicates and make
+    // sure redundant applications are idempotent
+    glm::vec3 _lastUpdatedPositionValue;
+    glm::quat  _lastUpdatedRotationValue;
+    glm::vec3 _lastUpdatedVelocityValue;
+    glm::vec3 _lastUpdatedAngularVelocityValue;
+    glm::vec3 _lastUpdatedAccelerationValue;
+
+    quint64 _lastUpdatedPositionTimestamp { 0 };
+    quint64 _lastUpdatedRotationTimestamp { 0 };
+    quint64 _lastUpdatedVelocityTimestamp { 0 };
+    quint64 _lastUpdatedAngularVelocityTimestamp { 0 };
+    quint64 _lastUpdatedAccelerationTimestamp { 0 };
+
+
 };
 
 #endif // hifi_EntityItem_h
diff --git a/libraries/gpu/src/gpu/Transform.slh b/libraries/gpu/src/gpu/Transform.slh
index 078b19d494..246167e186 100644
--- a/libraries/gpu/src/gpu/Transform.slh
+++ b/libraries/gpu/src/gpu/Transform.slh
@@ -119,6 +119,15 @@ TransformObject getTransformObject() {
     }
 <@endfunc@>
 
+<@func transformModelToWorldDir(cameraTransform, objectTransform, modelDir, worldDir)@>
+    { // transformModelToEyeDir
+        vec3 mr0 = <$objectTransform$>._modelInverse[0].xyz;
+        vec3 mr1 = <$objectTransform$>._modelInverse[1].xyz;
+        vec3 mr2 = <$objectTransform$>._modelInverse[2].xyz;
+
+        <$worldDir$> = vec3(dot(mr0, <$modelDir$>), dot(mr1, <$modelDir$>), dot(mr2, <$modelDir$>));
+    }
+<@endfunc@>
 
 <@func transformModelToEyeDir(cameraTransform, objectTransform, modelDir, eyeDir)@>
     { // transformModelToEyeDir
diff --git a/libraries/physics/src/CharacterController.cpp b/libraries/physics/src/CharacterController.cpp
index 1c8a9b50b5..30fb3536ca 100644
--- a/libraries/physics/src/CharacterController.cpp
+++ b/libraries/physics/src/CharacterController.cpp
@@ -401,11 +401,10 @@ glm::vec3 CharacterController::getLinearVelocity() const {
 }
 
 glm::vec3 CharacterController::getVelocityChange() const {
-    glm::vec3 velocity(0.0f);
     if (_rigidBody) {
-        velocity = bulletToGLM(_rigidBody->getLinearVelocity());
+        return bulletToGLM(_velocityChange);
     }
-    return velocity;
+    return glm::vec3(0.0f);
 }
 
 void CharacterController::clearMotors() {
diff --git a/libraries/plugins/src/plugins/DisplayPlugin.h b/libraries/plugins/src/plugins/DisplayPlugin.h
index 41f380aa86..1f6a16cd46 100644
--- a/libraries/plugins/src/plugins/DisplayPlugin.h
+++ b/libraries/plugins/src/plugins/DisplayPlugin.h
@@ -137,7 +137,7 @@ public:
     }
 
     // will query the underlying hmd api to compute the most recent head pose
-    virtual void beginFrameRender(uint32_t frameIndex) {}
+    virtual bool beginFrameRender(uint32_t frameIndex) { return true; }
 
     // returns a copy of the most recent head pose, computed via updateHeadPose
     virtual glm::mat4 getHeadPose() const {
@@ -170,6 +170,10 @@ public:
 
 signals:
     void recommendedFramebufferSizeChanged(const QSize & size);
+    // Indicates that this display plugin is no longer valid for use.
+    // For instance if a user exits Oculus Home or Steam VR while 
+    // using the corresponding plugin, that plugin should be disabled.
+    void outputDeviceLost();
 
 protected:
     void incrementPresentCount();
diff --git a/libraries/plugins/src/plugins/PluginManager.cpp b/libraries/plugins/src/plugins/PluginManager.cpp
index 936cb8a7ee..eb6465aab2 100644
--- a/libraries/plugins/src/plugins/PluginManager.cpp
+++ b/libraries/plugins/src/plugins/PluginManager.cpp
@@ -62,11 +62,10 @@ PluginManager::PluginManager() {
 extern DisplayPluginList getDisplayPlugins();
 extern InputPluginList getInputPlugins();
 extern void saveInputPluginSettings(const InputPluginList& plugins);
+static DisplayPluginList displayPlugins;
 
 const DisplayPluginList& PluginManager::getDisplayPlugins() {
-    static DisplayPluginList displayPlugins;
     static std::once_flag once;
-
     std::call_once(once, [&] {
         // Grab the built in plugins
         displayPlugins = ::getDisplayPlugins();
@@ -90,6 +89,16 @@ const DisplayPluginList& PluginManager::getDisplayPlugins() {
     return displayPlugins;
 }
 
+void PluginManager::disableDisplayPlugin(const QString& name) {
+    for (size_t i = 0; i < displayPlugins.size(); ++i) {
+        if (displayPlugins[i]->getName() == name) {
+            displayPlugins.erase(displayPlugins.begin() + i);
+            break;
+        }
+    }
+}
+
+
 const InputPluginList& PluginManager::getInputPlugins() {
     static InputPluginList inputPlugins;
     static std::once_flag once;
diff --git a/libraries/plugins/src/plugins/PluginManager.h b/libraries/plugins/src/plugins/PluginManager.h
index 2e056414ec..cf0b8efe64 100644
--- a/libraries/plugins/src/plugins/PluginManager.h
+++ b/libraries/plugins/src/plugins/PluginManager.h
@@ -17,6 +17,7 @@ public:
   PluginManager();
 
   const DisplayPluginList& getDisplayPlugins();
+  void disableDisplayPlugin(const QString& name);
   const InputPluginList& getInputPlugins();
   void saveSettings();
 };
diff --git a/libraries/render-utils/src/DeferredBuffer.slh b/libraries/render-utils/src/DeferredBuffer.slh
index aed89b30d0..b9c65a3bff 100755
--- a/libraries/render-utils/src/DeferredBuffer.slh
+++ b/libraries/render-utils/src/DeferredBuffer.slh
@@ -51,4 +51,70 @@ float packUnlit() {
     return FRAG_PACK_UNLIT;
 }
 
+
+vec2 signNotZero(vec2 v) {
+    return vec2((v.x >= 0.0) ? +1.0 : -1.0, (v.y >= 0.0) ? +1.0 : -1.0);
+}
+
+vec2 float32x3_to_oct(in vec3 v) {
+    vec2 p = v.xy * (1.0 / (abs(v.x) + abs(v.y) + abs(v.z)));
+    return ((v.z <= 0.0) ? ((1.0 - abs(p.yx)) * signNotZero(p)) : p);
+}
+
+
+vec3 oct_to_float32x3(in vec2 e) {
+    vec3 v = vec3(e.xy, 1.0 - abs(e.x) - abs(e.y));
+    if (v.z < 0) {
+        v.xy = (1.0 - abs(v.yx)) * signNotZero(v.xy);
+    }
+    return normalize(v);
+}
+
+vec3 snorm12x2_to_unorm8x3(vec2 f) {
+    vec2 u = vec2(round(clamp(f, -1.0, 1.0) * 2047.0 + 2047.0));
+    float t = floor(u.y / 256.0);
+
+    return floor(vec3(
+        u.x / 16.0,
+        fract(u.x / 16.0) * 256.0 + t,
+        u.y - t * 256.0
+        )) / 255.0;
+}
+
+vec2 unorm8x3_to_snorm12x2(vec3 u) {
+    u *= 255.0;
+    u.y *= (1.0 / 16.0);
+    vec2 s = vec2(  u.x * 16.0 + floor(u.y),
+                    fract(u.y) * (16.0 * 256.0) + u.z);
+    return clamp(s * (1.0 / 2047.0) - 1.0, vec2(-1.0), vec2(1.0));
+}
+
+uniform sampler2D normalFittingMap;
+
+vec3 bestFitNormal(vec3 normal) {
+    vec3 absNorm = abs(normal);
+    float maxNAbs = max(absNorm.z, max(absNorm.x, absNorm.y));
+
+    vec2 texcoord = (absNorm.z < maxNAbs ? 
+                        (absNorm.y < maxNAbs ? absNorm.yz : absNorm.xz) :
+                        absNorm.xy);
+    texcoord = (texcoord.x < texcoord.y ? texcoord.yx : texcoord.xy);
+    texcoord.y /= texcoord.x;
+    vec3 cN = normal / maxNAbs;
+
+    float fittingScale = texture(normalFittingMap, texcoord).a;
+    cN *= fittingScale;
+
+    return (cN * 0.5 + 0.5);
+}
+
+vec3 packNormal(in vec3 n) {
+    return snorm12x2_to_unorm8x3(float32x3_to_oct(n));
+}
+
+vec3 unpackNormal(in vec3 p) {
+    return oct_to_float32x3(unorm8x3_to_snorm12x2(p));
+}
+
+
 <@endif@>
diff --git a/libraries/render-utils/src/DeferredBufferRead.slh b/libraries/render-utils/src/DeferredBufferRead.slh
index 569063955d..7714859f5a 100644
--- a/libraries/render-utils/src/DeferredBufferRead.slh
+++ b/libraries/render-utils/src/DeferredBufferRead.slh
@@ -100,7 +100,7 @@ DeferredFragment unpackDeferredFragmentNoPosition(vec2 texcoord) {
     frag.obscurance = texture(obscuranceMap, texcoord).x;
 
     // Unpack the normal from the map
-    frag.normal = normalize(frag.normalVal.xyz * 2.0 - vec3(1.0));
+    frag.normal = unpackNormal(frag.normalVal.xyz);
     frag.roughness = frag.normalVal.a;
 
     // Diffuse color and unpack the mode and the metallicness
diff --git a/libraries/render-utils/src/DeferredBufferWrite.slh b/libraries/render-utils/src/DeferredBufferWrite.slh
index 2be38fbea3..e869f32dc6 100755
--- a/libraries/render-utils/src/DeferredBufferWrite.slh
+++ b/libraries/render-utils/src/DeferredBufferWrite.slh
@@ -17,24 +17,6 @@ layout(location = 0) out vec4 _fragColor0;
 layout(location = 1) out vec4 _fragColor1;
 layout(location = 2) out vec4 _fragColor2;
 
-uniform sampler2D normalFittingMap;
-
-vec3 bestFitNormal(vec3 normal) {
-    vec3 absNorm = abs(normal);
-    float maxNAbs = max(absNorm.z, max(absNorm.x, absNorm.y));
-
-    vec2 texcoord = (absNorm.z < maxNAbs ? 
-                        (absNorm.y < maxNAbs ? absNorm.yz : absNorm.xz) :
-                        absNorm.xy);
-    texcoord = (texcoord.x < texcoord.y ? texcoord.yx : texcoord.xy);
-    texcoord.y /= texcoord.x;
-    vec3 cN = normal / maxNAbs;
-
-    float fittingScale = texture(normalFittingMap, texcoord).a;
-    cN *= fittingScale;
-    return (cN * 0.5 + 0.5);
-}
-
 
 // the alpha threshold
 const float alphaThreshold = 0.5;
@@ -55,7 +37,7 @@ void packDeferredFragment(vec3 normal, float alpha, vec3 albedo, float roughness
         discard;
     }
     _fragColor0 = vec4(albedo, packShadedMetallic(metallic));
-    _fragColor1 = vec4(bestFitNormal(normal), clamp(roughness, 0.0, 1.0));
+    _fragColor1 = vec4(packNormal(normal), clamp(roughness, 0.0, 1.0));
     _fragColor2 = vec4(emissive, occlusion);
 }
 
@@ -65,7 +47,7 @@ void packDeferredFragmentLightmap(vec3 normal, float alpha, vec3 albedo, float r
         discard;
     }
     _fragColor0 = vec4(albedo, packLightmappedMetallic(metallic));
-    _fragColor1 = vec4(bestFitNormal(normal), clamp(roughness, 0.0, 1.0));
+    _fragColor1 = vec4(packNormal(normal), clamp(roughness, 0.0, 1.0));
     _fragColor2 = vec4(emissive, 1.0);
 }
 
@@ -74,7 +56,7 @@ void packDeferredFragmentUnlit(vec3 normal, float alpha, vec3 color) {
         discard;
     }
     _fragColor0 = vec4(color, packUnlit());
-    _fragColor1 = vec4(bestFitNormal(normal), 1.0);
+    _fragColor1 = vec4(packNormal(normal), 1.0);
     //_fragColor2 = vec4(vec3(0.0), 1.0); // If unlit, do not worry about the emissive color target
 }
 
diff --git a/libraries/render-utils/src/DeferredGlobalLight.slh b/libraries/render-utils/src/DeferredGlobalLight.slh
index 7608c8ae08..d29c8bea87 100755
--- a/libraries/render-utils/src/DeferredGlobalLight.slh
+++ b/libraries/render-utils/src/DeferredGlobalLight.slh
@@ -66,7 +66,8 @@ vec3 evalGlobalSpecularIrradiance(Light light, vec3 fragEyeDir, vec3 fragNormal,
     // prepareGlobalLight
 
     // Transform directions to worldspace
-    vec3 fragNormal = vec3(invViewMat * vec4(normal, 0.0));
+   // vec3 fragNormal = vec3(invViewMat * vec4(normal, 0.0));
+    vec3 fragNormal = vec3((normal));
     vec3 fragEyeVector = vec3(invViewMat * vec4(-position, 0.0));
     vec3 fragEyeDir = normalize(fragEyeVector);
 
diff --git a/libraries/render-utils/src/FramebufferCache.cpp b/libraries/render-utils/src/FramebufferCache.cpp
index 3223ee5535..2d322b1726 100644
--- a/libraries/render-utils/src/FramebufferCache.cpp
+++ b/libraries/render-utils/src/FramebufferCache.cpp
@@ -59,8 +59,8 @@ void FramebufferCache::createPrimaryFramebuffer() {
     _deferredFramebuffer = gpu::FramebufferPointer(gpu::Framebuffer::create());
     _deferredFramebufferDepthColor = gpu::FramebufferPointer(gpu::Framebuffer::create());
 
-   // auto colorFormat = gpu::Element::COLOR_RGBA_32;
     auto colorFormat = gpu::Element::COLOR_SRGBA_32;
+    auto linearFormat = gpu::Element::COLOR_RGBA_32;
     auto width = _frameBufferSize.width();
     auto height = _frameBufferSize.height();
 
@@ -70,7 +70,8 @@ void FramebufferCache::createPrimaryFramebuffer() {
     _primaryFramebuffer->setRenderBuffer(0, _primaryColorTexture);
 
     _deferredColorTexture = gpu::TexturePointer(gpu::Texture::create2D(colorFormat, width, height, defaultSampler));
-    _deferredNormalTexture = gpu::TexturePointer(gpu::Texture::create2D(colorFormat, width, height, defaultSampler));
+
+    _deferredNormalTexture = gpu::TexturePointer(gpu::Texture::create2D(linearFormat, width, height, defaultSampler));
     _deferredSpecularTexture = gpu::TexturePointer(gpu::Texture::create2D(colorFormat, width, height, defaultSampler));
 
     _deferredFramebuffer->setRenderBuffer(0, _deferredColorTexture);
diff --git a/libraries/render-utils/src/model.slv b/libraries/render-utils/src/model.slv
index f1989dcf76..825cb66a48 100755
--- a/libraries/render-utils/src/model.slv
+++ b/libraries/render-utils/src/model.slv
@@ -36,5 +36,5 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToEyeAndClipPos(cam, obj, inPosition, _position, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, inNormal.xyz, _normal)$>
+    <$transformModelToWorldDir(cam, obj, inNormal.xyz, _normal)$>
 }
diff --git a/libraries/render-utils/src/model_lightmap.slv b/libraries/render-utils/src/model_lightmap.slv
index f73b6a02a7..161ceed14c 100755
--- a/libraries/render-utils/src/model_lightmap.slv
+++ b/libraries/render-utils/src/model_lightmap.slv
@@ -39,6 +39,6 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToEyeAndClipPos(cam, obj, inPosition, _position, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, inNormal.xyz, _normal)$>
+    <$transformModelToWorldDir(cam, obj, inNormal.xyz, _normal)$>
 }
 
diff --git a/libraries/render-utils/src/model_lightmap_normal_map.slv b/libraries/render-utils/src/model_lightmap_normal_map.slv
index cb333f50e3..5fb60d9227 100755
--- a/libraries/render-utils/src/model_lightmap_normal_map.slv
+++ b/libraries/render-utils/src/model_lightmap_normal_map.slv
@@ -39,6 +39,6 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToEyeAndClipPos(cam, obj, inPosition, _position, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, inNormal.xyz, _normal)$>
-    <$transformModelToEyeDir(cam, obj, inTangent.xyz, _tangent)$>
+    <$transformModelToWorldDir(cam, obj, inNormal.xyz, _normal)$>
+    <$transformModelToWorldDir(cam, obj, inTangent.xyz, _tangent)$>
 }
diff --git a/libraries/render-utils/src/model_normal_map.slv b/libraries/render-utils/src/model_normal_map.slv
index ded37923c2..425dc204d9 100755
--- a/libraries/render-utils/src/model_normal_map.slv
+++ b/libraries/render-utils/src/model_normal_map.slv
@@ -39,6 +39,6 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToEyeAndClipPos(cam, obj, inPosition, _position, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, inNormal.xyz, _normal)$>
-    <$transformModelToEyeDir(cam, obj, inTangent.xyz, _tangent)$>
+    <$transformModelToWorldDir(cam, obj, inNormal.xyz, _normal)$>
+    <$transformModelToWorldDir(cam, obj, inTangent.xyz, _tangent)$>
 }
diff --git a/libraries/render-utils/src/overlay3D.slv b/libraries/render-utils/src/overlay3D.slv
index d39e5a2f01..ee28367413 100644
--- a/libraries/render-utils/src/overlay3D.slv
+++ b/libraries/render-utils/src/overlay3D.slv
@@ -32,5 +32,5 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToEyeAndClipPos(cam, obj, inPosition, _position, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, inNormal.xyz, _normal)$>
+    <$transformModelToWorldDir(cam, obj, inNormal.xyz, _normal)$>
 }
diff --git a/libraries/render-utils/src/point_light.slf b/libraries/render-utils/src/point_light.slf
index 8c9ff2c8ad..96cf7152d9 100644
--- a/libraries/render-utils/src/point_light.slf
+++ b/libraries/render-utils/src/point_light.slf
@@ -61,7 +61,7 @@ void main(void) {
     vec3 fragLightDir = fragLightVec / fragLightDistance;
 
     // Eval shading
-    vec3 fragNormal = vec3(invViewMat * vec4(frag.normal, 0.0));
+    vec3 fragNormal = vec3(frag.normal);
     vec4 fragEyeVector = invViewMat * vec4(-frag.position.xyz, 0.0);
     vec3 fragEyeDir = normalize(fragEyeVector.xyz);
     vec4 shading = evalFragShading(fragNormal, fragLightDir, fragEyeDir, frag.metallic, frag.specular, frag.roughness);
diff --git a/libraries/render-utils/src/sdf_text3D.slv b/libraries/render-utils/src/sdf_text3D.slv
index d8b7587789..29bc1a9e85 100644
--- a/libraries/render-utils/src/sdf_text3D.slv
+++ b/libraries/render-utils/src/sdf_text3D.slv
@@ -27,5 +27,5 @@ void main() {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToClipPos(cam, obj, inPosition, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, inNormal.xyz, _normal.xyz)$>
+    <$transformModelToWorldDir(cam, obj, inNormal.xyz, _normal.xyz)$>
 }
\ No newline at end of file
diff --git a/libraries/render-utils/src/simple.slv b/libraries/render-utils/src/simple.slv
index d56d1cc8e2..64d3e24192 100644
--- a/libraries/render-utils/src/simple.slv
+++ b/libraries/render-utils/src/simple.slv
@@ -34,5 +34,5 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToClipPos(cam, obj, inPosition, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, inNormal.xyz, _normal)$>
+    <$transformModelToWorldDir(cam, obj, inNormal.xyz, _normal)$>
 }
\ No newline at end of file
diff --git a/libraries/render-utils/src/skin_model.slv b/libraries/render-utils/src/skin_model.slv
index c8501b8ddf..c538c8321e 100755
--- a/libraries/render-utils/src/skin_model.slv
+++ b/libraries/render-utils/src/skin_model.slv
@@ -45,6 +45,5 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToEyeAndClipPos(cam, obj, position, _position, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, interpolatedNormal.xyz, interpolatedNormal.xyz)$>
-    _normal = interpolatedNormal.xyz;
+    <$transformModelToWorldDir(cam, obj, interpolatedNormal.xyz, _normal.xyz)$>
 }
diff --git a/libraries/render-utils/src/skin_model_normal_map.slv b/libraries/render-utils/src/skin_model_normal_map.slv
index db4b206405..b57a52f2e6 100755
--- a/libraries/render-utils/src/skin_model_normal_map.slv
+++ b/libraries/render-utils/src/skin_model_normal_map.slv
@@ -50,8 +50,8 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToEyeAndClipPos(cam, obj, position, _position, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, interpolatedNormal.xyz, interpolatedNormal.xyz)$>
-    <$transformModelToEyeDir(cam, obj, interpolatedTangent.xyz, interpolatedTangent.xyz)$>
+    <$transformModelToWorldDir(cam, obj, interpolatedNormal.xyz, interpolatedNormal.xyz)$>
+    <$transformModelToWorldDir(cam, obj, interpolatedTangent.xyz, interpolatedTangent.xyz)$>
 
     _normal = interpolatedNormal.xyz;
     _tangent = interpolatedTangent.xyz;
diff --git a/libraries/render-utils/src/spot_light.slf b/libraries/render-utils/src/spot_light.slf
index 4191ba3f63..e5bdac1325 100644
--- a/libraries/render-utils/src/spot_light.slf
+++ b/libraries/render-utils/src/spot_light.slf
@@ -68,7 +68,7 @@ void main(void) {
     }
 
     // Eval shading
-    vec3 fragNormal = vec3(invViewMat * vec4(frag.normal, 0.0));
+    vec3 fragNormal = vec3(frag.normal);
     vec4 fragEyeVector = invViewMat * vec4(-frag.position.xyz, 0.0);
     vec3 fragEyeDir = normalize(fragEyeVector.xyz);
     vec4 shading = evalFragShading(fragNormal, fragLightDir, fragEyeDir, frag.metallic, frag.specular, frag.roughness);
diff --git a/libraries/render-utils/src/standardTransformPNTC.slv b/libraries/render-utils/src/standardTransformPNTC.slv
index f7e72b6997..0ced5ba6e2 100644
--- a/libraries/render-utils/src/standardTransformPNTC.slv
+++ b/libraries/render-utils/src/standardTransformPNTC.slv
@@ -30,6 +30,6 @@ void main(void) {
     TransformCamera cam = getTransformCamera();
     TransformObject obj = getTransformObject();
     <$transformModelToClipPos(cam, obj, inPosition, gl_Position)$>
-    <$transformModelToEyeDir(cam, obj, inNormal.xyz, varNormal)$>
+    <$transformModelToWorldDir(cam, obj, inNormal.xyz, varNormal)$>
     varPosition = inPosition.xyz;
 }
\ No newline at end of file
diff --git a/plugins/oculus/src/OculusBaseDisplayPlugin.cpp b/plugins/oculus/src/OculusBaseDisplayPlugin.cpp
index 3b6545ae96..e9f8545cff 100644
--- a/plugins/oculus/src/OculusBaseDisplayPlugin.cpp
+++ b/plugins/oculus/src/OculusBaseDisplayPlugin.cpp
@@ -17,7 +17,7 @@ void OculusBaseDisplayPlugin::resetSensors() {
     _currentRenderFrameInfo.renderPose = glm::mat4(); // identity
 }
 
-void OculusBaseDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
+bool OculusBaseDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
     _currentRenderFrameInfo = FrameInfo();
     _currentRenderFrameInfo.sensorSampleTime = ovr_GetTimeInSeconds();;
     _currentRenderFrameInfo.predictedDisplayTime = ovr_GetPredictedDisplayTime(_session, frameIndex);
@@ -26,6 +26,7 @@ void OculusBaseDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
     _currentRenderFrameInfo.presentPose = _currentRenderFrameInfo.renderPose;
     Lock lock(_mutex);
     _frameInfos[frameIndex] = _currentRenderFrameInfo;
+    return true;
 }
 
 bool OculusBaseDisplayPlugin::isSupported() const {
diff --git a/plugins/oculus/src/OculusBaseDisplayPlugin.h b/plugins/oculus/src/OculusBaseDisplayPlugin.h
index ed6f1a36b3..3e2c223908 100644
--- a/plugins/oculus/src/OculusBaseDisplayPlugin.h
+++ b/plugins/oculus/src/OculusBaseDisplayPlugin.h
@@ -16,11 +16,11 @@
 class OculusBaseDisplayPlugin : public HmdDisplayPlugin {
     using Parent = HmdDisplayPlugin;
 public:
-    virtual bool isSupported() const override;
+    bool isSupported() const override;
 
     // Stereo specific methods
-    virtual void resetSensors() override final;
-    virtual void beginFrameRender(uint32_t frameIndex) override;
+    void resetSensors() override final;
+    bool beginFrameRender(uint32_t frameIndex) override;
     float getTargetFrameRate() const override { return _hmdDesc.DisplayRefreshRate; }
     
 
diff --git a/plugins/oculusLegacy/src/OculusLegacyDisplayPlugin.cpp b/plugins/oculusLegacy/src/OculusLegacyDisplayPlugin.cpp
index 753ff923dd..f89e71b829 100644
--- a/plugins/oculusLegacy/src/OculusLegacyDisplayPlugin.cpp
+++ b/plugins/oculusLegacy/src/OculusLegacyDisplayPlugin.cpp
@@ -40,13 +40,14 @@ void OculusLegacyDisplayPlugin::resetSensors() {
     ovrHmd_RecenterPose(_hmd);
 }
 
-void OculusLegacyDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
+bool OculusLegacyDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
     _currentRenderFrameInfo = FrameInfo();
     _currentRenderFrameInfo.predictedDisplayTime = _currentRenderFrameInfo.sensorSampleTime = ovr_GetTimeInSeconds();
     _trackingState = ovrHmd_GetTrackingState(_hmd, _currentRenderFrameInfo.predictedDisplayTime);
     _currentRenderFrameInfo.rawRenderPose = _currentRenderFrameInfo.renderPose = toGlm(_trackingState.HeadPose.ThePose);
     Lock lock(_mutex);
     _frameInfos[frameIndex] = _currentRenderFrameInfo;
+    return true;
 }
 
 bool OculusLegacyDisplayPlugin::isSupported() const {
diff --git a/plugins/oculusLegacy/src/OculusLegacyDisplayPlugin.h b/plugins/oculusLegacy/src/OculusLegacyDisplayPlugin.h
index 5900ad4c58..453a6f9168 100644
--- a/plugins/oculusLegacy/src/OculusLegacyDisplayPlugin.h
+++ b/plugins/oculusLegacy/src/OculusLegacyDisplayPlugin.h
@@ -27,7 +27,7 @@ public:
 
     // Stereo specific methods
     void resetSensors() override;
-    void beginFrameRender(uint32_t frameIndex) override;
+    bool beginFrameRender(uint32_t frameIndex) override;
 
     float getTargetFrameRate() const override;
 
diff --git a/plugins/openvr/src/OpenVrDisplayPlugin.cpp b/plugins/openvr/src/OpenVrDisplayPlugin.cpp
index dba8fca208..2e0bebeadd 100644
--- a/plugins/openvr/src/OpenVrDisplayPlugin.cpp
+++ b/plugins/openvr/src/OpenVrDisplayPlugin.cpp
@@ -121,7 +121,12 @@ void OpenVrDisplayPlugin::resetSensors() {
 }
 
 
-void OpenVrDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
+bool OpenVrDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
+    handleOpenVrEvents();
+    if (openVrQuitRequested()) {
+        emit outputDeviceLost();
+        return false;
+    }
     double displayFrequency = _system->GetFloatTrackedDeviceProperty(vr::k_unTrackedDeviceIndex_Hmd, vr::Prop_DisplayFrequency_Float);
     double frameDuration = 1.f / displayFrequency;
     double vsyncToPhotons = _system->GetFloatTrackedDeviceProperty(vr::k_unTrackedDeviceIndex_Hmd, vr::Prop_SecondsFromVsyncToPhotons_Float);
@@ -148,6 +153,7 @@ void OpenVrDisplayPlugin::beginFrameRender(uint32_t frameIndex) {
 
     Lock lock(_mutex);
     _frameInfos[frameIndex] = _currentRenderFrameInfo;
+    return true;
 }
 
 void OpenVrDisplayPlugin::hmdPresent() {
diff --git a/plugins/openvr/src/OpenVrDisplayPlugin.h b/plugins/openvr/src/OpenVrDisplayPlugin.h
index 75193c5c98..fda5e37c2a 100644
--- a/plugins/openvr/src/OpenVrDisplayPlugin.h
+++ b/plugins/openvr/src/OpenVrDisplayPlugin.h
@@ -18,16 +18,16 @@ const float TARGET_RATE_OpenVr = 90.0f;  // FIXME: get from sdk tracked device p
 class OpenVrDisplayPlugin : public HmdDisplayPlugin {
     using Parent = HmdDisplayPlugin;
 public:
-    virtual bool isSupported() const override;
-    virtual const QString& getName() const override { return NAME; }
+    bool isSupported() const override;
+    const QString& getName() const override { return NAME; }
 
-    virtual float getTargetFrameRate() const override { return TARGET_RATE_OpenVr; }
+    float getTargetFrameRate() const override { return TARGET_RATE_OpenVr; }
 
-    virtual void customizeContext() override;
+    void customizeContext() override;
 
     // Stereo specific methods
-    virtual void resetSensors() override;
-    virtual void beginFrameRender(uint32_t frameIndex) override;
+    void resetSensors() override;
+    bool beginFrameRender(uint32_t frameIndex) override;
     void cycleDebugOutput() override { _lockCurrentTexture = !_lockCurrentTexture; }
 
 protected:
diff --git a/plugins/openvr/src/OpenVrHelpers.cpp b/plugins/openvr/src/OpenVrHelpers.cpp
index 8536ffd5d9..155bc9f079 100644
--- a/plugins/openvr/src/OpenVrHelpers.cpp
+++ b/plugins/openvr/src/OpenVrHelpers.cpp
@@ -26,6 +26,11 @@ using Lock = std::unique_lock<Mutex>;
 static int refCount { 0 };
 static Mutex mutex;
 static vr::IVRSystem* activeHmd { nullptr };
+static bool _openVrQuitRequested { false };
+
+bool openVrQuitRequested() {
+    return _openVrQuitRequested;
+}
 
 static const uint32_t RELEASE_OPENVR_HMD_DELAY_MS = 5000;
 
@@ -56,17 +61,17 @@ vr::IVRSystem* acquireOpenVrSystem() {
     if (hmdPresent) {
         Lock lock(mutex);
         if (!activeHmd) {
-            qCDebug(displayplugins) << "openvr: No vr::IVRSystem instance active, building";
+            qCDebug(displayplugins) << "OpenVR: No vr::IVRSystem instance active, building";
             vr::EVRInitError eError = vr::VRInitError_None;
             activeHmd = vr::VR_Init(&eError, vr::VRApplication_Scene);
-            qCDebug(displayplugins) << "openvr display: HMD is " << activeHmd << " error is " << eError;
+            qCDebug(displayplugins) << "OpenVR display: HMD is " << activeHmd << " error is " << eError;
         }
         if (activeHmd) {
-            qCDebug(displayplugins) << "openvr: incrementing refcount";
+            qCDebug(displayplugins) << "OpenVR: incrementing refcount";
             ++refCount;
         }
     } else {
-        qCDebug(displayplugins) << "openvr: no hmd present";
+        qCDebug(displayplugins) << "OpenVR: no hmd present";
     }
     return activeHmd;
 }
@@ -74,12 +79,38 @@ vr::IVRSystem* acquireOpenVrSystem() {
 void releaseOpenVrSystem() {
     if (activeHmd) {
         Lock lock(mutex);
-        qCDebug(displayplugins) << "openvr: decrementing refcount";
+        qCDebug(displayplugins) << "OpenVR: decrementing refcount";
         --refCount;
         if (0 == refCount) {
-            qCDebug(displayplugins) << "openvr: zero refcount, deallocate VR system";
+            qCDebug(displayplugins) << "OpenVR: zero refcount, deallocate VR system";
             vr::VR_Shutdown();
+            _openVrQuitRequested = false;
             activeHmd = nullptr;
         }
     }
 }
+
+void handleOpenVrEvents() {
+    if (!activeHmd) {
+        return;
+    }
+    Lock lock(mutex);
+    if (!activeHmd) {
+        return;
+    }
+
+    vr::VREvent_t event;
+    while (activeHmd->PollNextEvent(&event, sizeof(event))) {
+        switch (event.eventType) {
+            case vr::VREvent_Quit:
+                _openVrQuitRequested = true;
+                activeHmd->AcknowledgeQuit_Exiting();
+                break;
+
+            default:
+                break;
+        }
+        qDebug() << "OpenVR: Event " << event.eventType;
+    }
+
+}
diff --git a/plugins/openvr/src/OpenVrHelpers.h b/plugins/openvr/src/OpenVrHelpers.h
index 4b06ca0813..1e5914844c 100644
--- a/plugins/openvr/src/OpenVrHelpers.h
+++ b/plugins/openvr/src/OpenVrHelpers.h
@@ -16,6 +16,8 @@ bool openVrSupported();
 
 vr::IVRSystem* acquireOpenVrSystem();
 void releaseOpenVrSystem();
+void handleOpenVrEvents();
+bool openVrQuitRequested();
 
 template<typename F>
 void openvr_for_each_eye(F f) {
diff --git a/plugins/openvr/src/ViveControllerManager.cpp b/plugins/openvr/src/ViveControllerManager.cpp
index 6e75454b5f..953501ccec 100644
--- a/plugins/openvr/src/ViveControllerManager.cpp
+++ b/plugins/openvr/src/ViveControllerManager.cpp
@@ -214,6 +214,11 @@ void ViveControllerManager::renderHand(const controller::Pose& pose, gpu::Batch&
 
 void ViveControllerManager::pluginUpdate(float deltaTime, const controller::InputCalibrationData& inputCalibrationData) {
     auto userInputMapper = DependencyManager::get<controller::UserInputMapper>();
+    handleOpenVrEvents();
+    if (openVrQuitRequested()) {
+        deactivate();
+        return;
+    }
 
     // because update mutates the internal state we need to lock
     userInputMapper->withLock([&, this]() {
diff --git a/script-archive/tests/audio/testPeakLimiter.js b/script-archive/tests/audio/testPeakLimiter.js
new file mode 100644
index 0000000000..d56126b912
--- /dev/null
+++ b/script-archive/tests/audio/testPeakLimiter.js
@@ -0,0 +1,19 @@
+var audioOptions = {
+  volume: 1.0,
+  loop: true,
+  position: MyAvatar.position
+}
+
+//var sineWave = Script.resolvePath("./1760sine.wav"); // use relative file
+var sineWave = "https://s3-us-west-1.amazonaws.com/highfidelity-dev/1760sine.wav"; // use file from S3
+var sound = SoundCache.getSound(sineWave);
+var injectorCount = 0;
+var MAX_INJECTOR_COUNT = 40;
+
+Script.update.connect(function() {
+    if (sound.downloaded && injectorCount < MAX_INJECTOR_COUNT) {
+        injectorCount++;
+        print("stating injector:" + injectorCount);
+        Audio.playSound(sound, audioOptions);
+    }
+}); 
\ No newline at end of file
diff --git a/tools/vhacd-util/src/VHACDUtil.cpp b/tools/vhacd-util/src/VHACDUtil.cpp
index 57ad185f45..9e28d33120 100644
--- a/tools/vhacd-util/src/VHACDUtil.cpp
+++ b/tools/vhacd-util/src/VHACDUtil.cpp
@@ -9,10 +9,12 @@
 //  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
 //
 
-#include <QVector>
 #include "VHACDUtil.h"
 
-const float COLLISION_TETRAHEDRON_SCALE = 0.25f;
+#include <unordered_map>
+#include <QVector>
+
+#include <NumericalConstants.h>
 
 
 // FBXReader jumbles the order of the meshes by reading them back out of a hashtable.  This will put
@@ -27,13 +29,16 @@ void reSortFBXGeometryMeshes(FBXGeometry& geometry) {
 
 // Read all the meshes from provided FBX file
 bool vhacd::VHACDUtil::loadFBX(const QString filename, FBXGeometry& result) {
+    if (_verbose) {
+        qDebug() << "reading FBX file =" << filename << "...";
+    }
 
     // open the fbx file
     QFile fbx(filename);
     if (!fbx.open(QIODevice::ReadOnly)) {
+        qWarning() << "unable to open FBX file =" << filename;
         return false;
     }
-    std::cout << "Reading FBX.....\n";
     try {
         QByteArray fbxContents = fbx.readAll();
         FBXGeometry* geom;
@@ -42,14 +47,14 @@ bool vhacd::VHACDUtil::loadFBX(const QString filename, FBXGeometry& result) {
         } else if (filename.toLower().endsWith(".fbx")) {
             geom = readFBX(fbxContents, QVariantHash(), filename);
         } else {
-            qDebug() << "unknown file extension";
+            qWarning() << "file has unknown extension" << filename;
             return false;
         }
         result = *geom;
 
         reSortFBXGeometryMeshes(result);
     } catch (const QString& error) {
-        qDebug() << "Error reading " << filename << ": " << error;
+        qWarning() << "error reading" << filename << ":" << error;
         return false;
     }
 
@@ -57,68 +62,62 @@ bool vhacd::VHACDUtil::loadFBX(const QString filename, FBXGeometry& result) {
 }
 
 
-unsigned int getTrianglesInMeshPart(const FBXMeshPart &meshPart, std::vector<int>& triangles) {
-    // append all the triangles (and converted quads) from this mesh-part to triangles
-    std::vector<int> meshPartTriangles = meshPart.triangleIndices.toStdVector();
-    triangles.insert(triangles.end(), meshPartTriangles.begin(), meshPartTriangles.end());
-
-    // convert quads to triangles
-    unsigned int triangleCount = meshPart.triangleIndices.size() / 3;
-    unsigned int quadCount = meshPart.quadIndices.size() / 4;
-    for (unsigned int i = 0; i < quadCount; i++) {
-        unsigned int p0Index = meshPart.quadIndices[i * 4];
-        unsigned int p1Index = meshPart.quadIndices[i * 4 + 1];
-        unsigned int p2Index = meshPart.quadIndices[i * 4 + 2];
-        unsigned int p3Index = meshPart.quadIndices[i * 4 + 3];
-        // split each quad into two triangles
-        triangles.push_back(p0Index);
-        triangles.push_back(p1Index);
-        triangles.push_back(p2Index);
-        triangles.push_back(p0Index);
-        triangles.push_back(p2Index);
-        triangles.push_back(p3Index);
-        triangleCount += 2;
+void getTrianglesInMeshPart(const FBXMeshPart &meshPart, std::vector<int>& triangleIndices) {
+    // append triangle indices
+    triangleIndices.reserve(triangleIndices.size() + (size_t)meshPart.triangleIndices.size());
+    for (auto index : meshPart.triangleIndices) {
+        triangleIndices.push_back(index);
     }
 
-    return triangleCount;
+    // convert quads to triangles
+    const uint32_t QUAD_STRIDE = 4;
+    uint32_t numIndices = (uint32_t)meshPart.quadIndices.size();
+    for (uint32_t i = 0; i < numIndices; i += QUAD_STRIDE) {
+        uint32_t p0Index = meshPart.quadIndices[i];
+        uint32_t p1Index = meshPart.quadIndices[i + 1];
+        uint32_t p2Index = meshPart.quadIndices[i + 2];
+        uint32_t p3Index = meshPart.quadIndices[i + 3];
+        // split each quad into two triangles
+        triangleIndices.push_back(p0Index);
+        triangleIndices.push_back(p1Index);
+        triangleIndices.push_back(p2Index);
+        triangleIndices.push_back(p0Index);
+        triangleIndices.push_back(p2Index);
+        triangleIndices.push_back(p3Index);
+    }
 }
 
-
-void vhacd::VHACDUtil::fattenMeshes(const FBXMesh& mesh, FBXMesh& result,
-                                    unsigned int& meshPartCount,
-                                    unsigned int startMeshIndex, unsigned int endMeshIndex) const {
+void vhacd::VHACDUtil::fattenMesh(const FBXMesh& mesh, const glm::mat4& geometryOffset, FBXMesh& result) const {
     // this is used to make meshes generated from a highfield collidable.  each triangle
     // is converted into a tetrahedron and made into its own mesh-part.
 
-    std::vector<int> triangles;
+    std::vector<int> triangleIndices;
     foreach (const FBXMeshPart &meshPart, mesh.parts) {
-        if (meshPartCount < startMeshIndex || meshPartCount >= endMeshIndex) {
-            meshPartCount++;
-            continue;
-        }
-        getTrianglesInMeshPart(meshPart, triangles);
+        getTrianglesInMeshPart(meshPart, triangleIndices);
     }
 
-    auto triangleCount = triangles.size() / 3;
-    if (triangleCount == 0) {
+    if (triangleIndices.size() == 0) {
         return;
     }
 
     int indexStartOffset = result.vertices.size();
 
     // new mesh gets the transformed points from the original
+    glm::mat4 totalTransform = geometryOffset * mesh.modelTransform;
     for (int i = 0; i < mesh.vertices.size(); i++) {
         // apply the source mesh's transform to the points
-        glm::vec4 v = mesh.modelTransform * glm::vec4(mesh.vertices[i], 1.0f);
+        glm::vec4 v = totalTransform * glm::vec4(mesh.vertices[i], 1.0f);
         result.vertices += glm::vec3(v);
     }
 
     // turn each triangle into a tetrahedron
 
-    for (unsigned int i = 0; i < triangleCount; i++) {
-        int index0 = triangles[i * 3] + indexStartOffset;
-        int index1 = triangles[i * 3 + 1] + indexStartOffset;
-        int index2 = triangles[i * 3 + 2] + indexStartOffset;
+    const uint32_t TRIANGLE_STRIDE = 3;
+    const float COLLISION_TETRAHEDRON_SCALE = 0.25f;
+    for (uint32_t i = 0; i < triangleIndices.size(); i += TRIANGLE_STRIDE) {
+        int index0 = triangleIndices[i] + indexStartOffset;
+        int index1 = triangleIndices[i + 1] + indexStartOffset;
+        int index2 = triangleIndices[i + 2] + indexStartOffset;
 
         // TODO: skip triangles with a normal that points more negative-y than positive-y
 
@@ -155,156 +154,304 @@ void vhacd::VHACDUtil::fattenMeshes(const FBXMesh& mesh, FBXMesh& result,
     }
 }
 
-
-
 AABox getAABoxForMeshPart(const FBXMesh& mesh, const FBXMeshPart &meshPart) {
     AABox aaBox;
-    unsigned int triangleCount = meshPart.triangleIndices.size() / 3;
-    for (unsigned int i = 0; i < triangleCount; ++i) {
-        aaBox += mesh.vertices[meshPart.triangleIndices[i * 3]];
-        aaBox += mesh.vertices[meshPart.triangleIndices[i * 3 + 1]];
-        aaBox += mesh.vertices[meshPart.triangleIndices[i * 3 + 2]];
+    const int TRIANGLE_STRIDE = 3;
+    for (int i = 0; i < meshPart.triangleIndices.size(); i += TRIANGLE_STRIDE) {
+        aaBox += mesh.vertices[meshPart.triangleIndices[i]];
+        aaBox += mesh.vertices[meshPart.triangleIndices[i + 1]];
+        aaBox += mesh.vertices[meshPart.triangleIndices[i + 2]];
     }
 
-    unsigned int quadCount = meshPart.quadIndices.size() / 4;
-    for (unsigned int i = 0; i < quadCount; ++i) {
-        aaBox += mesh.vertices[meshPart.quadIndices[i * 4]];
-        aaBox += mesh.vertices[meshPart.quadIndices[i * 4 + 1]];
-        aaBox += mesh.vertices[meshPart.quadIndices[i * 4 + 2]];
-        aaBox += mesh.vertices[meshPart.quadIndices[i * 4 + 3]];
+    const int QUAD_STRIDE = 4;
+    for (int i = 0; i < meshPart.quadIndices.size(); i += QUAD_STRIDE) {
+        aaBox += mesh.vertices[meshPart.quadIndices[i]];
+        aaBox += mesh.vertices[meshPart.quadIndices[i + 1]];
+        aaBox += mesh.vertices[meshPart.quadIndices[i + 2]];
+        aaBox += mesh.vertices[meshPart.quadIndices[i + 3]];
     }
 
     return aaBox;
 }
 
+class TriangleEdge {
+public:
+    TriangleEdge() {}
+    TriangleEdge(uint32_t A, uint32_t B) {
+        setIndices(A, B);
+    }
+    void setIndices(uint32_t A, uint32_t B) {
+        if (A < B) {
+            _indexA = A;
+            _indexB = B;
+        } else {
+            _indexA = B;
+            _indexB = A;
+        }
+    }
+    bool operator==(const TriangleEdge& other) const {
+        return _indexA == other._indexA && _indexB == other._indexB;
+    }
 
+    uint32_t getIndexA() const { return _indexA; }
+    uint32_t getIndexB() const { return _indexB; }
+private:
+    uint32_t _indexA { (uint32_t)(-1) };
+    uint32_t _indexB { (uint32_t)(-1) };
+};
+
+namespace std {
+    template <>
+    struct hash<TriangleEdge> {
+        std::size_t operator()(const TriangleEdge& edge) const {
+            // use Cantor's pairing function to generate a hash of ZxZ --> Z
+            uint32_t ab = edge.getIndexA() + edge.getIndexB();
+            return hash<int>()((ab * (ab + 1)) / 2 + edge.getIndexB());
+        }
+    };
+}
+
+// returns false if any edge has only one adjacent triangle
+bool isClosedManifold(const std::vector<int>& triangleIndices) {
+    using EdgeList = std::unordered_map<TriangleEdge, int>;
+    EdgeList edges;
+
+    // count the triangles for each edge
+    const uint32_t TRIANGLE_STRIDE = 3;
+    for (uint32_t i = 0; i < triangleIndices.size(); i += TRIANGLE_STRIDE) {
+        TriangleEdge edge;
+        // the triangles indices are stored in sequential order
+        for (uint32_t j = 0; j < 3; ++j) {
+            edge.setIndices(triangleIndices[i + j], triangleIndices[i + ((j + 1) % 3)]);
+
+            EdgeList::iterator edgeEntry = edges.find(edge);
+            if (edgeEntry == edges.end()) {
+                edges.insert(std::pair<TriangleEdge, uint32_t>(edge, 1));
+            } else {
+                edgeEntry->second += 1;
+            }
+        }
+    }
+    // scan for outside edge
+    for (auto& edgeEntry : edges) {
+        if (edgeEntry.second == 1) {
+             return false;
+        }
+    }
+    return true;
+}
+
+void vhacd::VHACDUtil::getConvexResults(VHACD::IVHACD* convexifier, FBXMesh& resultMesh) const {
+    // Number of hulls for this input meshPart
+    uint32_t numHulls = convexifier->GetNConvexHulls();
+    if (_verbose) {
+        qDebug() << "  hulls =" << numHulls;
+    }
+
+    // create an output meshPart for each convex hull
+    const uint32_t TRIANGLE_STRIDE = 3;
+    const uint32_t POINT_STRIDE = 3;
+    for (uint32_t j = 0; j < numHulls; j++) {
+        VHACD::IVHACD::ConvexHull hull;
+        convexifier->GetConvexHull(j, hull);
+
+        resultMesh.parts.append(FBXMeshPart());
+        FBXMeshPart& resultMeshPart = resultMesh.parts.last();
+
+        int hullIndexStart = resultMesh.vertices.size();
+        resultMesh.vertices.reserve(hullIndexStart + hull.m_nPoints);
+        uint32_t numIndices = hull.m_nPoints * POINT_STRIDE;
+        for (uint32_t i = 0; i < numIndices; i += POINT_STRIDE) {
+            float x = hull.m_points[i];
+            float y = hull.m_points[i + 1];
+            float z = hull.m_points[i + 2];
+            resultMesh.vertices.append(glm::vec3(x, y, z));
+        }
+
+        numIndices = hull.m_nTriangles * TRIANGLE_STRIDE;
+        resultMeshPart.triangleIndices.reserve(resultMeshPart.triangleIndices.size() + numIndices);
+        for (uint32_t i = 0; i < numIndices; i += TRIANGLE_STRIDE) {
+            resultMeshPart.triangleIndices.append(hull.m_triangles[i] + hullIndexStart);
+            resultMeshPart.triangleIndices.append(hull.m_triangles[i + 1] + hullIndexStart);
+            resultMeshPart.triangleIndices.append(hull.m_triangles[i + 2] + hullIndexStart);
+        }
+        if (_verbose) {
+            qDebug() << "    hull" << j << " vertices =" << hull.m_nPoints
+                << " triangles =" << hull.m_nTriangles
+                << " FBXMeshVertices =" << resultMesh.vertices.size();
+        }
+    }
+}
+
+float computeDt(uint64_t start) {
+    return (float)(usecTimestampNow() - start) / (float)USECS_PER_SECOND;
+}
 
 bool vhacd::VHACDUtil::computeVHACD(FBXGeometry& geometry,
                                     VHACD::IVHACD::Parameters params,
                                     FBXGeometry& result,
-                                    int startMeshIndex,
-                                    int endMeshIndex,
                                     float minimumMeshSize, float maximumMeshSize) {
+    if (_verbose) {
+        qDebug() << "meshes =" << geometry.meshes.size();
+    }
+
     // count the mesh-parts
-    int meshCount = 0;
+    int numParts = 0;
     foreach (const FBXMesh& mesh, geometry.meshes) {
-        meshCount += mesh.parts.size();
+        numParts += mesh.parts.size();
+    }
+    if (_verbose) {
+        qDebug() << "total parts =" << numParts;
     }
 
-    VHACD::IVHACD * interfaceVHACD = VHACD::CreateVHACD();
-
-    if (startMeshIndex < 0) {
-        startMeshIndex = 0;
-    }
-    if (endMeshIndex < 0) {
-        endMeshIndex = meshCount;
-    }
-
-    std::cout << "Performing V-HACD computation on " << endMeshIndex - startMeshIndex << " meshes ..... " << std::endl;
+    VHACD::IVHACD * convexifier = VHACD::CreateVHACD();
 
     result.meshExtents.reset();
     result.meshes.append(FBXMesh());
     FBXMesh &resultMesh = result.meshes.last();
 
-    int count = 0;
+    const uint32_t POINT_STRIDE = 3;
+    const uint32_t TRIANGLE_STRIDE = 3;
+
+    int meshIndex = 0;
+    int validPartsFound = 0;
     foreach (const FBXMesh& mesh, geometry.meshes) {
 
+        // find duplicate points
+        int numDupes = 0;
+        std::vector<int> dupeIndexMap;
+        dupeIndexMap.reserve(mesh.vertices.size());
+        for (int i = 0; i < mesh.vertices.size(); ++i) {
+            dupeIndexMap.push_back(i);
+            for (int j = 0; j < i; ++j) {
+                float distance = glm::distance2(mesh.vertices[i], mesh.vertices[j]);
+                const float MAX_DUPE_DISTANCE_SQUARED = 0.000001f;
+                if (distance < MAX_DUPE_DISTANCE_SQUARED) {
+                    dupeIndexMap[i] = j;
+                    ++numDupes;
+                    break;
+                }
+            }
+        }
+
         // each mesh has its own transform to move it to model-space
         std::vector<glm::vec3> vertices;
+        glm::mat4 totalTransform = geometry.offset * mesh.modelTransform;
         foreach (glm::vec3 vertex, mesh.vertices) {
-            vertices.push_back(glm::vec3(mesh.modelTransform * glm::vec4(vertex, 1.0f)));
+            vertices.push_back(glm::vec3(totalTransform * glm::vec4(vertex, 1.0f)));
         }
+        uint32_t numVertices = (uint32_t)vertices.size();
 
+        if (_verbose) {
+            qDebug() << "mesh" << meshIndex << ": "
+                << " parts =" << mesh.parts.size() << " clusters =" << mesh.clusters.size()
+                << " vertices =" << numVertices;
+        }
+        ++meshIndex;
+
+        std::vector<int> openParts;
+
+        int partIndex = 0;
+        std::vector<int> triangleIndices;
         foreach (const FBXMeshPart &meshPart, mesh.parts) {
-
-            if (count < startMeshIndex || count >= endMeshIndex) {
-                count ++;
-                continue;
-            }
-
-            qDebug() << "--------------------";
-
-            std::vector<int> triangles;
-            unsigned int triangleCount = getTrianglesInMeshPart(meshPart, triangles);
+            triangleIndices.clear();
+            getTrianglesInMeshPart(meshPart, triangleIndices);
 
             // only process meshes with triangles
-            if (triangles.size() <= 0) {
-                qDebug() << " Skipping (no triangles)...";
-                count++;
+            if (triangleIndices.size() <= 0) {
+                if (_verbose) {
+                    qDebug() << "  skip part" << partIndex << "(zero triangles)";
+                }
+                ++partIndex;
                 continue;
             }
 
-            auto nPoints = vertices.size();
+            // collapse dupe indices
+            for (auto& index : triangleIndices) {
+                index = dupeIndexMap[index];
+            }
+
             AABox aaBox = getAABoxForMeshPart(mesh, meshPart);
             const float largestDimension = aaBox.getLargestDimension();
 
-            qDebug() << "Mesh " << count << " -- " << nPoints << " points, " << triangleCount << " triangles, "
-                     << "size =" << largestDimension;
-
             if (largestDimension < minimumMeshSize) {
-                qDebug() << " Skipping (too small)...";
-                count++;
+                if (_verbose) {
+                    qDebug() << "  skip part" << partIndex << ":  dimension =" << largestDimension << "(too small)";
+                }
+                ++partIndex;
                 continue;
             }
 
             if (maximumMeshSize > 0.0f && largestDimension > maximumMeshSize) {
-                qDebug() << " Skipping (too large)...";
-                count++;
+                if (_verbose) {
+                    qDebug() << "  skip part" << partIndex << ":  dimension =" << largestDimension << "(too large)";
+                }
+                ++partIndex;
                 continue;
             }
 
+            // figure out if the mesh is a closed manifold or not
+            bool closed = isClosedManifold(triangleIndices);
+            if (closed) {
+                uint32_t triangleCount = (uint32_t)(triangleIndices.size()) / TRIANGLE_STRIDE;
+                if (_verbose) {
+                    qDebug() << "  process closed part" << partIndex << ": " << " triangles =" << triangleCount;
+                }
+
+                // compute approximate convex decomposition
+                bool success = convexifier->Compute(&vertices[0].x, POINT_STRIDE, numVertices,
+                        &triangleIndices[0], TRIANGLE_STRIDE, triangleCount, params);
+                if (success) {
+                    getConvexResults(convexifier, resultMesh);
+                } else if (_verbose) {
+                    qDebug() << "  failed to convexify";
+                }
+            } else {
+                if (_verbose) {
+                    qDebug() << "  postpone open part" << partIndex;
+                }
+                openParts.push_back(partIndex);
+            }
+            ++partIndex;
+            ++validPartsFound;
+        }
+        if (! openParts.empty()) {
+            // combine open meshes in an attempt to produce a closed mesh
+
+            triangleIndices.clear();
+            for (auto index : openParts) {
+                const FBXMeshPart &meshPart = mesh.parts[index];
+                getTrianglesInMeshPart(meshPart, triangleIndices);
+            }
+
+            // collapse dupe indices
+            for (auto& index : triangleIndices) {
+                index = dupeIndexMap[index];
+            }
+
+            // this time we don't care if the parts are closed or not
+            uint32_t triangleCount = (uint32_t)(triangleIndices.size()) / TRIANGLE_STRIDE;
+            if (_verbose) {
+                qDebug() << "  process remaining open parts =" << openParts.size() << ": "
+                    << " triangles =" << triangleCount;
+            }
 
             // compute approximate convex decomposition
-            bool res = interfaceVHACD->Compute(&vertices[0].x, 3, (uint)nPoints, &triangles[0], 3, triangleCount, params);
-            if (!res){
-                qDebug() << "V-HACD computation failed for Mesh : " << count;
-                count++;
-                continue;
+            bool success = convexifier->Compute(&vertices[0].x, POINT_STRIDE, numVertices,
+                    &triangleIndices[0], TRIANGLE_STRIDE, triangleCount, params);
+            if (success) {
+                getConvexResults(convexifier, resultMesh);
+            } else if (_verbose) {
+                qDebug() << "  failed to convexify";
             }
-
-            // Number of hulls for this input meshPart
-            unsigned int nConvexHulls = interfaceVHACD->GetNConvexHulls();
-
-            // create an output meshPart for each convex hull
-            for (unsigned int j = 0; j < nConvexHulls; j++) {
-                VHACD::IVHACD::ConvexHull hull;
-                interfaceVHACD->GetConvexHull(j, hull);
-
-                resultMesh.parts.append(FBXMeshPart());
-                FBXMeshPart &resultMeshPart = resultMesh.parts.last();
-
-                int hullIndexStart = resultMesh.vertices.size();
-                for (unsigned int i = 0; i < hull.m_nPoints; i++) {
-                    float x = hull.m_points[i * 3];
-                    float y = hull.m_points[i * 3 + 1];
-                    float z = hull.m_points[i * 3 + 2];
-                    resultMesh.vertices.append(glm::vec3(x, y, z));
-                }
-
-                for (unsigned int i = 0; i < hull.m_nTriangles; i++) {
-                    int index0 = hull.m_triangles[i * 3] + hullIndexStart;
-                    int index1 = hull.m_triangles[i * 3 + 1] + hullIndexStart;
-                    int index2 = hull.m_triangles[i * 3 + 2] + hullIndexStart;
-                    resultMeshPart.triangleIndices.append(index0);
-                    resultMeshPart.triangleIndices.append(index1);
-                    resultMeshPart.triangleIndices.append(index2);
-                }
-            }
-
-            count++;
         }
     }
 
     //release memory
-    interfaceVHACD->Clean();
-    interfaceVHACD->Release();
+    convexifier->Clean();
+    convexifier->Release();
 
-    if (count > 0){
-        return true;
-    }        
-    else{
-        return false;
-    }
+    return validPartsFound > 0;
 }
 
 vhacd::VHACDUtil:: ~VHACDUtil(){
@@ -319,16 +466,9 @@ void vhacd::ProgressCallback::Update(const double overallProgress,
                                      const char* const operation) {
     int progress = (int)(overallProgress + 0.5);
 
-    if (progress < 10){
-        std::cout << "\b\b";
-    }
-    else{
-        std::cout << "\b\b\b";
-    }
-
-    std::cout << progress << "%";
-
-    if (progress >= 100){
+    std::cout << "\b\b\b";
+    std::cout << progress << "%" << std::flush;
+    if (progress >= 100) {
         std::cout << std::endl;
     }
 }
diff --git a/tools/vhacd-util/src/VHACDUtil.h b/tools/vhacd-util/src/VHACDUtil.h
index 34c2c22e0e..8f82c4e4e4 100644
--- a/tools/vhacd-util/src/VHACDUtil.h
+++ b/tools/vhacd-util/src/VHACDUtil.h
@@ -25,18 +25,23 @@
 namespace vhacd {
     class VHACDUtil {
     public:
+        void setVerbose(bool verbose) { _verbose = verbose; }
+
         bool loadFBX(const QString filename, FBXGeometry& result);
 
-        void fattenMeshes(const FBXMesh& mesh, FBXMesh& result,
-                          unsigned int& meshPartCount,
-                          unsigned int startMeshIndex, unsigned int endMeshIndex) const;
+        void fattenMesh(const FBXMesh& mesh, const glm::mat4& gometryOffset, FBXMesh& result) const;
 
         bool computeVHACD(FBXGeometry& geometry,
                           VHACD::IVHACD::Parameters params,
                           FBXGeometry& result,
-                          int startMeshIndex, int endMeshIndex,
                           float minimumMeshSize, float maximumMeshSize);
+
+        void getConvexResults(VHACD::IVHACD* convexifier, FBXMesh& resultMesh) const;
+
         ~VHACDUtil();
+
+    private:
+        bool _verbose { false };
     };
 
     class ProgressCallback : public VHACD::IVHACD::IUserCallback {
@@ -45,7 +50,7 @@ namespace vhacd {
         ~ProgressCallback();
 
         // Couldn't follow coding guideline here due to virtual function declared in IUserCallback
-        void Update(const double overallProgress, const double stageProgress, const double operationProgress, 
+        void Update(const double overallProgress, const double stageProgress, const double operationProgress,
             const char * const stage, const char * const operation);
     };
 }
diff --git a/tools/vhacd-util/src/VHACDUtilApp.cpp b/tools/vhacd-util/src/VHACDUtilApp.cpp
index 2af6bca337..cae184a49c 100644
--- a/tools/vhacd-util/src/VHACDUtilApp.cpp
+++ b/tools/vhacd-util/src/VHACDUtilApp.cpp
@@ -19,7 +19,6 @@ using namespace std;
 using namespace VHACD;
 
 
-
 QString formatFloat(double n) {
     // limit precision to 6, but don't output trailing zeros.
     QString s = QString::number(n, 'f', 6);
@@ -33,14 +32,15 @@ QString formatFloat(double n) {
 }
 
 
-bool writeOBJ(QString outFileName, FBXGeometry& geometry, bool outputCentimeters, int whichMeshPart = -1) {
+bool VHACDUtilApp::writeOBJ(QString outFileName, FBXGeometry& geometry, bool outputCentimeters, int whichMeshPart) {
     QFile file(outFileName);
     if (!file.open(QIODevice::WriteOnly)) {
-        qDebug() << "Unable to write to " << outFileName;
+        qWarning() << "unable to write to" << outFileName;
+        _returnCode = VHACD_RETURN_CODE_FAILURE_TO_WRITE;
         return false;
     }
-    QTextStream out(&file);
 
+    QTextStream out(&file);
     if (outputCentimeters) {
         out << "# This file uses centimeters as units\n\n";
     }
@@ -105,6 +105,9 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
 
     const QCommandLineOption helpOption = parser.addHelpOption();
 
+    const QCommandLineOption verboseOutput("v", "verbose output");
+    parser.addOption(verboseOutput);
+
     const QCommandLineOption splitOption("split", "split input-file into one mesh per output-file");
     parser.addOption(splitOption);
 
@@ -123,12 +126,6 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
     const QCommandLineOption outputCentimetersOption("c", "output units are centimeters");
     parser.addOption(outputCentimetersOption);
 
-    const QCommandLineOption startMeshIndexOption("s", "start-mesh index", "0");
-    parser.addOption(startMeshIndexOption);
-
-    const QCommandLineOption endMeshIndexOption("e", "end-mesh index", "0");
-    parser.addOption(endMeshIndexOption);
-
     const QCommandLineOption minimumMeshSizeOption("m", "minimum mesh (diagonal) size to consider", "0");
     parser.addOption(minimumMeshSizeOption);
 
@@ -195,8 +192,10 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
         Q_UNREACHABLE();
     }
 
-    bool outputCentimeters = parser.isSet(outputCentimetersOption);
+    bool verbose = parser.isSet(verboseOutput);
+    vUtil.setVerbose(verbose);
 
+    bool outputCentimeters = parser.isSet(outputCentimetersOption);
     bool fattenFaces = parser.isSet(fattenFacesOption);
     bool generateHulls = parser.isSet(generateHullsOption);
     bool splitModel = parser.isSet(splitOption);
@@ -225,16 +224,6 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
         Q_UNREACHABLE();
     }
 
-    int startMeshIndex = -1;
-    if (parser.isSet(startMeshIndexOption)) {
-        startMeshIndex = parser.value(startMeshIndexOption).toInt();
-    }
-
-    int endMeshIndex = -1;
-    if (parser.isSet(endMeshIndexOption)) {
-        endMeshIndex = parser.value(endMeshIndexOption).toInt();
-    }
-
     float minimumMeshSize = 0.0f;
     if (parser.isSet(minimumMeshSizeOption)) {
         minimumMeshSize = parser.value(minimumMeshSizeOption).toFloat();
@@ -301,17 +290,20 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
         Q_UNREACHABLE();
     }
 
-
-    // load the mesh 
-
+    // load the mesh
     FBXGeometry fbx;
     auto begin = std::chrono::high_resolution_clock::now();
     if (!vUtil.loadFBX(inputFilename, fbx)){
-        cout << "Error in opening FBX file....";
+        _returnCode = VHACD_RETURN_CODE_FAILURE_TO_READ;
+        return;
     }
     auto end = std::chrono::high_resolution_clock::now();
-    auto loadDuration = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin).count();
 
+    if (verbose) {
+        auto loadDuration = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin).count();
+        const double NANOSECS_PER_SECOND = 1.0e9;
+        qDebug() << "load time =" << (double)loadDuration / NANOSECS_PER_SECOND << "seconds";
+    }
 
     if (splitModel) {
         QVector<QString> infileExtensions = {"fbx", "obj"};
@@ -329,10 +321,14 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
 
     if (generateHulls) {
         VHACD::IVHACD::Parameters params;
-        vhacd::ProgressCallback pCallBack;
+        vhacd::ProgressCallback progressCallback;
 
         //set parameters for V-HACD
-        params.m_callback = &pCallBack; //progress callback
+        if (verbose) {
+            params.m_callback = &progressCallback; //progress callback
+        } else {
+            params.m_callback = nullptr;
+        }
         params.m_resolution = vHacdResolution;
         params.m_depth = vHacdDepth;
         params.m_concavity = vHacdConcavity;
@@ -346,44 +342,51 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
         params.m_mode = 0; // 0: voxel-based (recommended), 1: tetrahedron-based
         params.m_maxNumVerticesPerCH = vHacdMaxVerticesPerCH;
         params.m_minVolumePerCH = 0.0001; // 0.0001
-        params.m_callback = 0; // 0
-        params.m_logger = 0; // 0
+        params.m_logger = nullptr;
         params.m_convexhullApproximation = true; // true
         params.m_oclAcceleration = true; // true
 
         //perform vhacd computation
+        if (verbose) {
+            qDebug() << "running V-HACD algorithm ...";
+        }
         begin = std::chrono::high_resolution_clock::now();
 
         FBXGeometry result;
-        if (!vUtil.computeVHACD(fbx, params, result, startMeshIndex, endMeshIndex,
-                                minimumMeshSize, maximumMeshSize)) {
-            cout << "Compute Failed...";
-        }
+        bool success = vUtil.computeVHACD(fbx, params, result, minimumMeshSize, maximumMeshSize);
+
         end = std::chrono::high_resolution_clock::now();
         auto computeDuration = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin).count();
+        if (verbose) {
+            qDebug() << "run time =" << (double)computeDuration / 1000000000.00 << " seconds";
+        }
+
+        if (!success) {
+            if (verbose) {
+                qDebug() << "failed to convexify model";
+            }
+            _returnCode = VHACD_RETURN_CODE_FAILURE_TO_CONVEXIFY;
+            return;
+        }
 
         int totalVertices = 0;
         int totalTriangles = 0;
-        int totalMeshParts = 0;
         foreach (const FBXMesh& mesh, result.meshes) {
             totalVertices += mesh.vertices.size();
             foreach (const FBXMeshPart &meshPart, mesh.parts) {
                 totalTriangles += meshPart.triangleIndices.size() / 3;
                 // each quad was made into two triangles
                 totalTriangles += 2 * meshPart.quadIndices.size() / 4;
-                totalMeshParts++;
             }
         }
 
-        int totalHulls = result.meshes[0].parts.size();
-        cout << endl << "Summary of V-HACD Computation..................." << endl;
-        cout << "File Path          : " << inputFilename.toStdString() << endl;
-        cout << "Number Of Meshes   : " << totalMeshParts << endl;
-        cout << "Total vertices     : " << totalVertices << endl;
-        cout << "Total Triangles    : " << totalTriangles << endl;
-        cout << "Total Convex Hulls : " << totalHulls << endl;
-        cout << "Total FBX load time: " << (double)loadDuration / 1000000000.00 << " seconds" << endl;
-        cout << "V-HACD Compute time: " << (double)computeDuration / 1000000000.00 << " seconds" << endl;
+        if (verbose) {
+            int totalHulls = result.meshes[0].parts.size();
+            qDebug() << "output file =" << outputFilename;
+            qDebug() << "vertices =" << totalVertices;
+            qDebug() << "triangles =" << totalTriangles;
+            qDebug() << "hulls =" << totalHulls;
+        }
 
         writeOBJ(outputFilename, result, outputCentimeters);
     }
@@ -398,17 +401,9 @@ VHACDUtilApp::VHACDUtilApp(int argc, char* argv[]) :
             meshCount += mesh.parts.size();
         }
 
-        if (startMeshIndex < 0) {
-            startMeshIndex = 0;
-        }
-        if (endMeshIndex < 0) {
-            endMeshIndex = meshCount;
-        }
-
-        unsigned int meshPartCount = 0;
         result.modelTransform = glm::mat4(); // Identity matrix
         foreach (const FBXMesh& mesh, fbx.meshes) {
-            vUtil.fattenMeshes(mesh, result, meshPartCount, startMeshIndex, endMeshIndex);
+            vUtil.fattenMesh(mesh, fbx.offset, result);
         }
 
         newFbx.meshes.append(result);
diff --git a/tools/vhacd-util/src/VHACDUtilApp.h b/tools/vhacd-util/src/VHACDUtilApp.h
index 016b7b7b2f..ebb8164634 100644
--- a/tools/vhacd-util/src/VHACDUtilApp.h
+++ b/tools/vhacd-util/src/VHACDUtilApp.h
@@ -15,12 +15,25 @@
 
 #include <QApplication>
 
+#include <FBXReader.h>
+
+const int VHACD_RETURN_CODE_FAILURE_TO_READ = 1;
+const int VHACD_RETURN_CODE_FAILURE_TO_WRITE = 2;
+const int VHACD_RETURN_CODE_FAILURE_TO_CONVEXIFY = 3;
+
 
 class VHACDUtilApp : public QCoreApplication {
     Q_OBJECT
- public:
+public:
     VHACDUtilApp(int argc, char* argv[]);
     ~VHACDUtilApp();
+
+    bool writeOBJ(QString outFileName, FBXGeometry& geometry, bool outputCentimeters, int whichMeshPart = -1);
+
+    int getReturnCode() const { return _returnCode; }
+
+private:
+    int _returnCode { 0 };
 };
 
 
diff --git a/tools/vhacd-util/src/main.cpp b/tools/vhacd-util/src/main.cpp
index 0e8d72abd3..42c9db9513 100644
--- a/tools/vhacd-util/src/main.cpp
+++ b/tools/vhacd-util/src/main.cpp
@@ -23,5 +23,5 @@ using namespace VHACD;
 
 int main(int argc, char * argv[]) {
     VHACDUtilApp app(argc, argv);
-    return 0;
+    return app.getReturnCode();
 }