diff --git a/toonz/sources/common/tvrender/qtofflinegl.cpp b/toonz/sources/common/tvrender/qtofflinegl.cpp
index 0793b00..4c8eca5 100644
--- a/toonz/sources/common/tvrender/qtofflinegl.cpp
+++ b/toonz/sources/common/tvrender/qtofflinegl.cpp
@@ -78,10 +78,12 @@ void rightRotateBits(UCHAR *buf, int bufferSize)
 
 //-----------------------------------------------------------------------------
 
-QtOfflineGL::QtOfflineGL(TDimension rasterSize, const TOfflineGL::Imp *shared)
-	: TOfflineGL::Imp(rasterSize.lx, rasterSize.ly), m_context(0), m_oldContext(0)
+QtOfflineGL::QtOfflineGL(TDimension rasterSize, std::shared_ptr<TOfflineGL::Imp> shared)
+	: TOfflineGL::Imp(rasterSize.lx, rasterSize.ly)
+	, m_context(0)
+	, m_oldContext(0)
 {
-	createContext(rasterSize, shared);
+	createContext(rasterSize, std::move(shared));
 	/*
   makeCurrent();
 
@@ -101,7 +103,7 @@ QtOfflineGL::~QtOfflineGL()
 
 //-----------------------------------------------------------------------------
 
-void QtOfflineGL::createContext(TDimension rasterSize, const TOfflineGL::Imp *shared)
+void QtOfflineGL::createContext(TDimension rasterSize, std::shared_ptr<TOfflineGL::Imp> shared)
 {
 	// Imposto il formato dei Pixel (pixelFormat)
 	/*
diff --git a/toonz/sources/common/tvrender/tofflinegl.cpp b/toonz/sources/common/tvrender/tofflinegl.cpp
index 6ed5cd5..bccfb70 100644
--- a/toonz/sources/common/tvrender/tofflinegl.cpp
+++ b/toonz/sources/common/tvrender/tofflinegl.cpp
@@ -87,7 +87,7 @@ public:
 		: TOfflineGL::Imp(rasterSize.lx, rasterSize.ly)
 	{
 		m_offData = 0;
-		createContext(rasterSize, shared); //makeCurrent is called at the end of this
+		createContext(rasterSize, std::move(shared)); //makeCurrent is called at the end of this
 
 		glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
 		glClear(GL_COLOR_BUFFER_BIT);
diff --git a/toonz/sources/include/qtofflinegl.h b/toonz/sources/include/qtofflinegl.h
index 5fd8316..f0e6022 100644
--- a/toonz/sources/include/qtofflinegl.h
+++ b/toonz/sources/include/qtofflinegl.h
@@ -1,8 +1,8 @@
-
-
 #ifndef QTOFFLINEGL_H
 #define QTOFFLINEGL_H
 
+#include <memory>
+
 #include <QtOpenGL>
 #include <QGLFormat>
 #include <QGLContext>
@@ -17,10 +17,10 @@ public:
 	QOpenGLContext *m_oldContext;
 	QOffscreenSurface *m_surface;
 
-	QtOfflineGL(TDimension rasterSize, const TOfflineGL::Imp *shared = 0);
+	QtOfflineGL(TDimension rasterSize, std::shared_ptr<TOfflineGL::Imp> shared);
 	~QtOfflineGL();
 
-	void createContext(TDimension rasterSize, const TOfflineGL::Imp *shared);
+	void createContext(TDimension rasterSize, std::shared_ptr<TOfflineGL::Imp> shared);
 	void makeCurrent();
 	void doneCurrent();