From d2a0d96f955dde8d0d26c0b5c3e98f7b396de80d Mon Sep 17 00:00:00 2001
From: Wenzel Jakob <wenzel@cs.cornell.edu>
Date: Fri, 4 Mar 2011 00:17:43 +0100
Subject: [PATCH] OpenMP initialization code

---
 include/mitsuba/core/thread.h |  3 +++
 src/libcore/thread.cpp        | 36 +++++++++++++++++++++++++++++++++++
 src/librender/gatherproc.cpp  |  4 ++--
 3 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/include/mitsuba/core/thread.h b/include/mitsuba/core/thread.h
index 5e46d273..f1da81fb 100644
--- a/include/mitsuba/core/thread.h
+++ b/include/mitsuba/core/thread.h
@@ -147,6 +147,9 @@ public:
 	/// Shut down the threading system
 	static void staticShutdown();
 
+	/// Initialize Mitsuba's threading system for simultaneous use of OpenMP
+	static void initializeOpenMP();
+
 	MTS_DECLARE_CLASS()
 protected:
 	/// Virtual destructor
diff --git a/src/libcore/thread.cpp b/src/libcore/thread.cpp
index 7a952167..e2f4caac 100644
--- a/src/libcore/thread.cpp
+++ b/src/libcore/thread.cpp
@@ -39,6 +39,21 @@ protected:
 	virtual ~MainThread() { }
 };
 
+class OpenMPThread : public Thread {
+public:
+	OpenMPThread() : Thread("main") {
+	}
+
+	virtual void run() {
+		Log(EError, "The OpenMP thread is already running!");
+	}
+
+	MTS_DECLARE_CLASS()
+protected:
+	virtual ~OpenMPThread() { }
+};
+
+
 ThreadLocal<Thread> *Thread::m_self = NULL;
 
 #if defined(__LINUX__) || defined(__OSX__)
@@ -278,6 +293,26 @@ void Thread::staticShutdown() {
 #endif
 }
 
+void Thread::initializeOpenMP() {
+	ref<Logger> logger = Thread::getThread()->getLogger();
+	ref<FileResolver> fResolver = Thread::getThread()->getFileResolver();
+
+	#pragma omp parallel
+	{
+		Thread *thread = Thread::getThread();
+		if (!thread) {
+			thread = new OpenMPThread();
+			thread->m_running = true;
+			thread->m_thread = pthread_self();
+			thread->m_joinMutex = new Mutex();
+			thread->m_joined = false;
+			thread->m_fresolver = fResolver;
+			thread->m_logger = logger;
+			m_self->set(thread);
+		}
+	}
+}
+
 Thread::~Thread() {
 	if (m_running)
 		Log(EWarn, "Destructor called while Thread '%s' is still running", m_name.c_str());
@@ -285,4 +320,5 @@ Thread::~Thread() {
 
 MTS_IMPLEMENT_CLASS(Thread, true, Object)
 MTS_IMPLEMENT_CLASS(MainThread, false, Thread)
+MTS_IMPLEMENT_CLASS(OpenMPThread, false, Thread)
 MTS_NAMESPACE_END
diff --git a/src/librender/gatherproc.cpp b/src/librender/gatherproc.cpp
index 19a621bc..1419efaa 100644
--- a/src/librender/gatherproc.cpp
+++ b/src/librender/gatherproc.cpp
@@ -124,8 +124,8 @@ public:
 			m_workResult->put(PhotonMap::Photon(its.p, its.geoFrame.n, -its.toWorld(its.wi), weight, depth));
 	}
 
-	void handleMediumInteraction(int depth, bool caustic, const MediumSamplingRecord &mRec, const Vector &wi, 
-		const Spectrum &weight) {
+	void handleMediumInteraction(int depth, bool caustic, const MediumSamplingRecord &mRec, Float time, 
+			const Vector &wi, const Spectrum &weight) {
 		if (m_type == GatherPhotonProcess::EVolumePhotons && depth > 1)
 			m_workResult->put(PhotonMap::Photon(mRec.p, Normal(), -wi, weight, depth));
 	}