diff --git a/gui_qt/baseexplorerchunk.cpp b/gui_qt/baseexplorerchunk.cpp
index 34867de..70b6379 100644
--- a/gui_qt/baseexplorerchunk.cpp
+++ b/gui_qt/baseexplorerchunk.cpp
@@ -3,10 +3,10 @@
 BaseExplorerChunk::BaseExplorerChunk(Renderer* renderer)
 {
     _renderer = renderer;
-    
+
     priority = 0.0;
     _reset_needed = false;
-    
+
     _texture = new QImage(1, 1, QImage::Format_ARGB32);
     _texture_id = 0;
     _texture_changed = false;
@@ -24,7 +24,7 @@ BaseExplorerChunk::~BaseExplorerChunk()
 bool BaseExplorerChunk::maintain()
 {
     bool subchanged;
-    
+
     _lock_data.lock();
     if (_reset_needed)
     {
@@ -33,9 +33,9 @@ bool BaseExplorerChunk::maintain()
         onResetEvent();
     }
     _lock_data.unlock();
-    
+
     subchanged = onMaintainEvent();
-    
+
     // Improve texture resolution
     if (_texture_current_size < _texture_max_size)
     {
@@ -60,7 +60,7 @@ bool BaseExplorerChunk::maintain()
         _texture_current_size = new_texture_size;
         _texture_changed = true;
         _lock_data.unlock();
-        
+
         return true;
     }
     else
@@ -108,7 +108,7 @@ void BaseExplorerChunk::render(QGLWidget* widget)
         glBindTexture(GL_TEXTURE_2D, _texture_id);
     }
     _lock_data.unlock();
-    
+
     // Delegate poly rendering to subclass
     onRenderEvent(widget);
 }
@@ -123,7 +123,7 @@ void BaseExplorerChunk::setMaxTextureSize(int size)
     _texture_max_size = size;
 }
 
-void BaseExplorerChunk::onCameraEvent(CameraDefinition* camera)
+void BaseExplorerChunk::onCameraEvent(CameraDefinition*)
 {
 }
 
@@ -136,16 +136,16 @@ bool BaseExplorerChunk::onMaintainEvent()
     return false;
 }
 
-void BaseExplorerChunk::onRenderEvent(QGLWidget* widget)
+void BaseExplorerChunk::onRenderEvent(QGLWidget*)
 {
 }
 
-double BaseExplorerChunk::getDisplayedSizeHint(CameraDefinition* camera)
+double BaseExplorerChunk::getDisplayedSizeHint(CameraDefinition*)
 {
     return 0.0;
 }
 
-Color BaseExplorerChunk::getTextureColor(double x, double y)
+Color BaseExplorerChunk::getTextureColor(double, double)
 {
     return COLOR_TRANSPARENT;
 }
\ No newline at end of file
diff --git a/gui_qt/dialogcolorgradation.cpp b/gui_qt/dialogcolorgradation.cpp
index aa0a658..7071444 100644
--- a/gui_qt/dialogcolorgradation.cpp
+++ b/gui_qt/dialogcolorgradation.cpp
@@ -21,18 +21,18 @@ DialogColorGradation::DialogColorGradation(QWidget *parent, ColorGradation* grad
     QWidget* form;
     QGridLayout* form_layout;
     QLabel* label;
-    
+
     _base = gradation;
     _current = colorGradationCreate();
     colorGradationCopy(_base, _current);
 
     setLayout(new QVBoxLayout());
-    
+
     form = new QWidget(this);
     form_layout = new QGridLayout();
     form->setLayout(form_layout);
     layout()->addWidget(form);
-    
+
     label = new QLabel(tr("This is the curve editor for color components.\nClick on a component preview below to edit it.\nClick on points and drag them to move them.\nDouble click to add a new point.\nRight click on a point to delete it."), form);
     label->setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::Minimum);
     label->setMinimumWidth(150);
@@ -94,11 +94,11 @@ DialogColorGradation::DialogColorGradation(QWidget *parent, ColorGradation* grad
     _preview_final->setMaximumHeight(60);
     _preview_final->setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);
     form_layout->addWidget(_preview_final, 4, 0);
-    
+
     buttons = new QWidget(this);
     layout()->addWidget(buttons);
     buttons->setLayout(new QHBoxLayout());
-    
+
     _button_accept = new QPushButton(tr("Validate"), buttons);
     buttons->layout()->addWidget(_button_accept);
     QObject::connect(_button_accept, SIGNAL(clicked()), this, SLOT(accept()));
@@ -137,7 +137,7 @@ bool DialogColorGradation::getGradation(QWidget* parent, ColorGradation* gradati
     return (result != 0) ? true : false;
 }
 
-void DialogColorGradation::closeEvent(QCloseEvent* e)
+void DialogColorGradation::closeEvent(QCloseEvent*)
 {
     reject();
 }
@@ -182,10 +182,10 @@ void DialogColorGradation::selectBlue()
 void DialogColorGradation::updateColors()
 {
     Curve* curve;
-    
+
     curve = curveCreate();
     _curve_editor->getCurve(curve);
-    
+
     switch (_selected)
     {
     case 0:
@@ -209,7 +209,7 @@ void DialogColorGradation::updateColors()
         ;
     }
     _preview_final->update();
-    
+
     curveDelete(curve);
 }
 
diff --git a/gui_qt/dialogrender.cpp b/gui_qt/dialogrender.cpp
index 773c084..c17bfbe 100644
--- a/gui_qt/dialogrender.cpp
+++ b/gui_qt/dialogrender.cpp
@@ -15,9 +15,12 @@ static DialogRender* _current_dialog;
 
 static void _renderStart(int width, int height, Color background)
 {
+    _current_dialog->pixbuf_lock->lock();
     delete _current_dialog->pixbuf;
     _current_dialog->pixbuf = new QImage(width, height, QImage::Format_ARGB32);
     _current_dialog->pixbuf->fill(colorToQColor(background).rgb());
+    _current_dialog->pixbuf_lock->unlock();
+
     _current_dialog->tellRenderSize(width, height);
 }
 
@@ -61,18 +64,21 @@ public:
     void paintEvent(QPaintEvent*)
     {
         QPainter painter(this);
+        _current_dialog->pixbuf_lock->lock();
         painter.drawImage(0, 0, *_current_dialog->pixbuf);
+        _current_dialog->pixbuf_lock->unlock();
     }
 };
 
 DialogRender::DialogRender(QWidget *parent, Renderer* renderer):
     QDialog(parent, Qt::WindowTitleHint | Qt::WindowMaximizeButtonHint | Qt::WindowMinimizeButtonHint | Qt::WindowCloseButtonHint)
 {
+    pixbuf_lock = new QMutex();
     pixbuf = new QImage(1, 1, QImage::Format_ARGB32);
     _current_dialog = this;
     _render_thread = NULL;
     _renderer = renderer;
-    
+
     setModal(true);
     setWindowTitle(tr("Paysages 3D - Render"));
     setLayout(new QVBoxLayout());
@@ -82,21 +88,21 @@ DialogRender::DialogRender(QWidget *parent, Renderer* renderer):
     area = new RenderArea(_scroll);
     _scroll->setWidget(area);
     layout()->addWidget(_scroll);
-    
+
     _info = new QWidget(this);
     _info->setLayout(new QHBoxLayout());
     layout()->addWidget(_info);
 
     _timer = new QLabel(QString("0:00.00"), _info);
     _info->layout()->addWidget(_timer);
-    
+
     _progress = new QProgressBar(_info);
     _progress->setMaximumHeight(12);
     _progress->setMinimum(0);
     _progress->setMaximum(1000);
     _progress->setValue(0);
     _info->layout()->addWidget(_progress);
-    
+
     connect(this, SIGNAL(renderSizeChanged(int, int)), this, SLOT(applyRenderSize(int, int)));
     connect(this, SIGNAL(progressChanged(double)), this, SLOT(applyProgress(double)));
 }
@@ -111,6 +117,7 @@ DialogRender::~DialogRender()
         delete _render_thread;
     }
     delete pixbuf;
+    delete pixbuf_lock;
 }
 
 void DialogRender::tellRenderSize(int width, int height)
@@ -126,7 +133,7 @@ void DialogRender::tellProgressChange(double value)
 void DialogRender::startRender(RenderParams params)
 {
     _started = time(NULL);
-    
+
     //applyRenderSize(params.width, params.height);
     rendererSetPreviewCallbacks(_renderer, _renderStart, _renderDraw, _renderUpdate);
 
diff --git a/gui_qt/dialogrender.h b/gui_qt/dialogrender.h
index 0a5c7ee..ad0d49b 100644
--- a/gui_qt/dialogrender.h
+++ b/gui_qt/dialogrender.h
@@ -7,6 +7,7 @@
 #include <QProgressBar>
 #include <QScrollArea>
 #include <QLabel>
+#include <QMutex>
 #include "../lib_paysages/renderer.h"
 
 class DialogRender : public QDialog
@@ -22,12 +23,13 @@ public:
     void loadLastRender();
 
     QImage* pixbuf;
+    QMutex* pixbuf_lock;
     QWidget* area;
-    
+
 private slots:
     void applyRenderSize(int width, int height);
     void applyProgress(double value);
-    
+
 signals:
     void renderSizeChanged(int width, int height);
     void progressChanged(double value);
diff --git a/gui_qt/formrender.cpp b/gui_qt/formrender.cpp
index 3f3746d..f792ea4 100644
--- a/gui_qt/formrender.cpp
+++ b/gui_qt/formrender.cpp
@@ -91,7 +91,7 @@ private:
         lightingGetStatus((LightingDefinition*)renderer->customData[2], renderer, location, status);
     }
 
-    static Color _applyAerialPerspective(Renderer* renderer, Vector3 location, Color base)
+    static Color _applyAerialPerspective(Renderer*, Vector3, Color base)
     {
         return base;
     }