From bc256f3e8f01ce07b5740f00099e7dac59c1b4ef Mon Sep 17 00:00:00 2001
From: "Anthony J. Thibault" <tony@highfidelity.io>
Date: Thu, 2 Mar 2017 14:42:06 -0800
Subject: [PATCH] Fix for multi-threaded access to maps in DebugDraw.

---
 libraries/shared/src/DebugDraw.cpp | 30 ++++++++++++++++++++++++++++++
 libraries/shared/src/DebugDraw.h   | 10 ++++++----
 2 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/libraries/shared/src/DebugDraw.cpp b/libraries/shared/src/DebugDraw.cpp
index 549dbb7293..f17671da4d 100644
--- a/libraries/shared/src/DebugDraw.cpp
+++ b/libraries/shared/src/DebugDraw.cpp
@@ -10,6 +10,8 @@
 #include "DebugDraw.h"
 #include "SharedUtil.h"
 
+using Lock = std::unique_lock<std::mutex>;
+
 DebugDraw& DebugDraw::getInstance() {
     static DebugDraw* instance = globalInstance<DebugDraw>("com.highfidelity.DebugDraw");
     return *instance;
@@ -25,22 +27,50 @@ DebugDraw::~DebugDraw() {
 
 // world space line, drawn only once
 void DebugDraw::drawRay(const glm::vec3& start, const glm::vec3& end, const glm::vec4& color) {
+    Lock lock(_mapMutex);
     _rays.push_back(Ray(start, end, color));
 }
 
 void DebugDraw::addMarker(const QString& key, const glm::quat& rotation, const glm::vec3& position, const glm::vec4& color) {
+    Lock lock(_mapMutex);
     _markers[key] = MarkerInfo(rotation, position, color);
 }
 
 void DebugDraw::removeMarker(const QString& key) {
+    Lock lock(_mapMutex);
     _markers.erase(key);
 }
 
 void DebugDraw::addMyAvatarMarker(const QString& key, const glm::quat& rotation, const glm::vec3& position, const glm::vec4& color) {
+    Lock lock(_mapMutex);
     _myAvatarMarkers[key] = MarkerInfo(rotation, position, color);
 }
 
 void DebugDraw::removeMyAvatarMarker(const QString& key) {
+    Lock lock(_mapMutex);
     _myAvatarMarkers.erase(key);
 }
 
+//
+// accessors used by renderer
+//
+
+DebugDraw::MarkerMap DebugDraw::getMarkerMap() const {
+    Lock lock(_mapMutex);
+    return _markers;
+}
+
+DebugDraw::MarkerMap DebugDraw::getMyAvatarMarkerMap() const {
+    Lock lock(_mapMutex);
+    return _myAvatarMarkers;
+}
+
+DebugDraw::Rays DebugDraw::getRays() const {
+    Lock lock(_mapMutex);
+    return _rays;
+}
+
+void DebugDraw::clearRays() {
+    Lock lock(_mapMutex);
+    _rays.clear();
+}
diff --git a/libraries/shared/src/DebugDraw.h b/libraries/shared/src/DebugDraw.h
index ac7e8b3cbc..64327585fb 100644
--- a/libraries/shared/src/DebugDraw.h
+++ b/libraries/shared/src/DebugDraw.h
@@ -10,6 +10,7 @@
 #ifndef hifi_DebugDraw_h
 #define hifi_DebugDraw_h
 
+#include <mutex>
 #include <unordered_map>
 #include <tuple>
 #include <string>
@@ -87,16 +88,17 @@ public:
     // accessors used by renderer
     //
 
-    const MarkerMap& getMarkerMap() const { return _markers; }
-    const MarkerMap& getMyAvatarMarkerMap() const { return _myAvatarMarkers; }
+    MarkerMap getMarkerMap() const;
+    MarkerMap getMyAvatarMarkerMap() const;
     void updateMyAvatarPos(const glm::vec3& pos) { _myAvatarPos = pos; }
     const glm::vec3& getMyAvatarPos() const { return _myAvatarPos; }
     void updateMyAvatarRot(const glm::quat& rot) { _myAvatarRot = rot; }
     const glm::quat& getMyAvatarRot() const { return _myAvatarRot; }
-    const Rays getRays() const { return _rays; }
-    void clearRays() { _rays.clear(); }
+    Rays getRays() const;
+    void clearRays();
 
 protected:
+    mutable std::mutex _mapMutex;
     MarkerMap _markers;
     MarkerMap _myAvatarMarkers;
     glm::quat _myAvatarRot;