diff --git a/sources/demo/Context.cpp b/sources/demo/Context.cpp
index 8f7d9144..343914ee 100755
--- a/sources/demo/Context.cpp
+++ b/sources/demo/Context.cpp
@@ -16,64 +16,64 @@
 * You should have received a copy of the GNU Lesser General Public License *
 * along with ReactPhysics3D. If not, see <http://www.gnu.org/licenses/>.   *
 ***************************************************************************/
-
-// Libraries
-#include "Context.h"
-#include "../reactphysics3d/reactphysics3d.h"
-#include <iostream>
-#include <vector>
+
+// Libraries
+#include "Context.h"
+#include "../reactphysics3d/reactphysics3d.h"
+#include <iostream>
+#include <vector>
 
 // We want to use the ReactPhysics3D namespace
-using namespace reactphysics3d;
-
-// Constructor of the class Context
-Context::Context() {
-
-    Cube* cube1 = new Cube(Vector3D(11.0,14.0, 4.0), Quaternion(1.0, 1.0, 0.0, 0.0), 4.0, Kilogram(3.0));
+using namespace reactphysics3d;
+
+// Constructor of the class Context
+Context::Context() {
+
+    Cube* cube1 = new Cube(Vector3D(5.0,14.0, 4.0), Quaternion(1.0, 1.0, 0.0, 0.0), 4.0, Kilogram(3.0));
     cube1->getRigidBody()->setLinearVelocity(Vector3D(0.0, -5.0, 0.0));
 
-    //Cube* cube2 = new Cube(Vector3D(0.0, 17, 8.0), Quaternion(0.0, 1.0, 0.0, 0.0), 3.0, Kilogram(2.0));
-    //Cube* cube3 = new Cube(Vector3D(4.0, 17, -2.0), Quaternion(0.0, 1.0, 0.0, 0.0), 2.0, Kilogram(11.0));
+    //Cube* cube2 = new Cube(Vector3D(0.0, 17, 8.0), Quaternion(0.0, 1.0, 0.0, 0.0), 3.0, Kilogram(2.0));
+    //Cube* cube3 = new Cube(Vector3D(4.0, 17, -2.0), Quaternion(0.0, 1.0, 0.0, 0.0), 2.0, Kilogram(11.0));
     Plane* plane1 = new Plane(Vector3D(0.0, 0.0, 0.0), Quaternion(0.0, 1.0, 0.0, 0.0), 20.0, 30.0, Vector3D(-1.0, 0.0, 0.0), Vector3D(0.0, 0.0, 1.0), Kilogram(10.0));
-
-    addObject(cube1);
-    //addObject(cube2);
-    //addObject(cube3);
-    addObject(plane1);
-}
-
-
-// Destructor of the class Context
-Context::~Context() {
-    // Delete all the objects in vectObjects
-    for(unsigned int i=0; i<vectObjects.size(); ++i) {
-        delete vectObjects[i];
-    }
-}
-
-// Method to get an object from the context
-Object& Context::getObject(int objectIndex) const {
-    // TODO : WE HAVE TO ADD HERE AN EXCEPTION IMPLEMENTATION
-
-    // Return the object from the context
-    return (*vectObjects.at(objectIndex));     // TODO : THROWN AN EXCEPTION IF INDEX IS OUT OF THE BOUNDS
-}
-
-// Method for adding an object into the context
-void Context::addObject(Object* object) {
-    if (object != 0) {
-        // Add the object into the context
-        vectObjects.push_back(object);
-    }
-}
-
-// Method to remove an object from the context
-void Context::removeObject(int objectIndex) {
-    // WE HAVE TO ADD HERE AN EXCEPTION IMPLEMENTATION
-
-    // Restore the memory of the element
-    delete vectObjects[objectIndex];
-
-    // Erase the element in the vector
-    vectObjects.erase(vectObjects.begin()+objectIndex);
-}
+
+    addObject(cube1);
+    //addObject(cube2);
+    //addObject(cube3);
+    addObject(plane1);
+}
+
+
+// Destructor of the class Context
+Context::~Context() {
+    // Delete all the objects in vectObjects
+    for(unsigned int i=0; i<vectObjects.size(); ++i) {
+        delete vectObjects[i];
+    }
+}
+
+// Method to get an object from the context
+Object& Context::getObject(int objectIndex) const {
+    // TODO : WE HAVE TO ADD HERE AN EXCEPTION IMPLEMENTATION
+
+    // Return the object from the context
+    return (*vectObjects.at(objectIndex));     // TODO : THROWN AN EXCEPTION IF INDEX IS OUT OF THE BOUNDS
+}
+
+// Method for adding an object into the context
+void Context::addObject(Object* object) {
+    if (object != 0) {
+        // Add the object into the context
+        vectObjects.push_back(object);
+    }
+}
+
+// Method to remove an object from the context
+void Context::removeObject(int objectIndex) {
+    // WE HAVE TO ADD HERE AN EXCEPTION IMPLEMENTATION
+
+    // Restore the memory of the element
+    delete vectObjects[objectIndex];
+
+    // Erase the element in the vector
+    vectObjects.erase(vectObjects.begin()+objectIndex);
+}
diff --git a/sources/demo/Scene.cpp b/sources/demo/Scene.cpp
index 2ab5cfdf..5bb3f284 100755
--- a/sources/demo/Scene.cpp
+++ b/sources/demo/Scene.cpp
@@ -16,106 +16,106 @@
  * You should have received a copy of the GNU Lesser General Public License *
  * along with ReactPhysics3D. If not, see <http://www.gnu.org/licenses/>.   *
  ***************************************************************************/
-
-// Librairies
-#include "Scene.h"
+
+// Librairies
+#include "Scene.h"
 #include "Objects.h"
 #include <GL/gl.h>
-#include <GL/glu.h>
-
-// Constructor of the class Scene
+#include <GL/glu.h>
+
+// Constructor of the class Scene
 Scene::Scene(rp3d::PhysicsWorld* world) {
 
     this->world = world;
-
-    // Initialise the material specular color
-    mat_specular[0] = 1.0;
-    mat_specular[1] = 1.0;
-    mat_specular[2] = 1.0;
-    mat_specular[3] = 1.0;
-
-    // Initialize the material shininess
-    mat_shininess[0] = 50.0;
-
-    // Initialise the light source position
-    light_position[0] = 20.0;
-    light_position[1] = 9.0;
-    light_position[2] = 15.0;
-    light_position[3] = 0.0;
-
-    // Initialise the ambient color of the light
-    ambient_color[0] = 1.0;
-    ambient_color[1] = 1.0;
-    ambient_color[2] = 1.0;
-    ambient_color[3] = 0.7;
-
-    // Initialise the diffuse light color
-    white_light[0] = 1.0;
-    white_light[1] = 1.0;
-    white_light[2] = 1.0;
-    white_light[3] = 1.0;
-}
-
-// Destructor of the class Scene
-Scene::~Scene() {
-
-}
-
-// Init method
-void Scene::init() {
-    glClearColor(0.0, 0.0, 0.0, 0.0);           // Select the color for the background
-    glShadeModel(GL_SMOOTH);
-    glClearDepth(1.0);
-
-    // Lighting settings
-    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);        // Specular color of the material
-    glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);      // Shininess of the material
-    glLightfv(GL_LIGHT0, GL_POSITION, light_position);        // Position of the light source
-    glLightfv(GL_LIGHT0, GL_AMBIENT, ambient_color);          // Ambient color of the light
-    glLightfv(GL_LIGHT0, GL_DIFFUSE, white_light);            // Diffuse color of the light
-    glLightfv(GL_LIGHT0, GL_SPECULAR, white_light);           // Specular color of the light
-
-    glEnable(GL_LIGHTING);                                    // Activate the lighting
-    glEnable(GL_LIGHT0);                                      // Activate a light source
+
+    // Initialise the material specular color
+    mat_specular[0] = 1.0;
+    mat_specular[1] = 1.0;
+    mat_specular[2] = 1.0;
+    mat_specular[3] = 1.0;
+
+    // Initialize the material shininess
+    mat_shininess[0] = 50.0;
+
+    // Initialise the light source position
+    light_position[0] = 20.0;
+    light_position[1] = 9.0;
+    light_position[2] = 15.0;
+    light_position[3] = 0.0;
+
+    // Initialise the ambient color of the light
+    ambient_color[0] = 1.0;
+    ambient_color[1] = 1.0;
+    ambient_color[2] = 1.0;
+    ambient_color[3] = 0.7;
+
+    // Initialise the diffuse light color
+    white_light[0] = 1.0;
+    white_light[1] = 1.0;
+    white_light[2] = 1.0;
+    white_light[3] = 1.0;
+}
+
+// Destructor of the class Scene
+Scene::~Scene() {
+
+}
+
+// Init method
+void Scene::init() {
+    glClearColor(0.0, 0.0, 0.0, 0.0);           // Select the color for the background
+    glShadeModel(GL_SMOOTH);
+    glClearDepth(1.0);
+
+    // Lighting settings
+    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);        // Specular color of the material
+    glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);      // Shininess of the material
+    glLightfv(GL_LIGHT0, GL_POSITION, light_position);        // Position of the light source
+    glLightfv(GL_LIGHT0, GL_AMBIENT, ambient_color);          // Ambient color of the light
+    glLightfv(GL_LIGHT0, GL_DIFFUSE, white_light);            // Diffuse color of the light
+    glLightfv(GL_LIGHT0, GL_SPECULAR, white_light);           // Specular color of the light
+
+    glEnable(GL_LIGHTING);                                    // Activate the lighting
+    glEnable(GL_LIGHT0);                                      // Activate a light source
     glEnable(GL_DEPTH_TEST);                                  // Activate the Depth buffer
-    //glEnable(GL_CULL_FACE);
-}
-
-// Display method
-void Scene::display(const Context& context) const {
-    glClearColor(0,0,0,0);
-	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-    glMatrixMode(GL_MODELVIEW);
-	glLoadIdentity();
-
-    // Define the position and the direction of the camera
+    //glEnable(GL_CULL_FACE);
+}
+
+// Display method
+void Scene::display(const Context& context) const {
+    glClearColor(0,0,0,0);
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+
+    // Define the position and the direction of the camera
 	//gluLookAt(30,10,0,0,0,0,0,1,0);
 	double x = outsideCamera.getPosition().getX();
 	double y = outsideCamera.getPosition().getY();
-	double z = outsideCamera.getPosition().getZ();
-    gluLookAt(x,y,z,0,0,0,0,1,0);
-
-    // Draw all objects in the context
-    for(int i=0; i<context.getNbObjects(); ++i)
-    {
-        // Copy the active matrix on the matrix stack
-       glPushMatrix();
-
-        // Draw the object
+	double z = outsideCamera.getPosition().getZ();
+    gluLookAt(x,y,z,0,0,0,0,1,0);
+
+    // Draw all objects in the context
+    for(int i=0; i<context.getNbObjects(); ++i)
+    {
+        // Copy the active matrix on the matrix stack
+       glPushMatrix();
+
+        // Draw the object
         context.getObject(i).draw();
 
        glPopMatrix();
        glPushMatrix();
 
         // Draw the bounding volume
-        context.getObject(i).getRigidBody()->getOBB().draw();
-
-       // Remove the matrix on the top of the matrix stack
-       glPopMatrix();
+        context.getObject(i).getRigidBody()->getOBB()->draw();
+
+       // Remove the matrix on the top of the matrix stack
+       glPopMatrix();
     }
 
     // Draw all the contact points
-    for (std::vector<Constraint*>::const_iterator it = world->getConstraintListStartIterator(); it != world->getConstraintListEndIterator(); ++it) {
+    for (std::vector<Constraint*>::iterator it = world->getConstraintsBeginIterator(); it != world->getConstraintsEndIterator(); ++it) {
         RigidBody* rigidBody1 = dynamic_cast<RigidBody*>((*it)->getBody1());
         RigidBody* rigidBody2 = dynamic_cast<RigidBody*>((*it)->getBody2());
         rigidBody1->setIsMotionEnabled(false);
@@ -125,24 +125,22 @@ void Scene::display(const Context& context) const {
         assert(contact != 0);
 
         // Draw the contact points
-        for (unsigned int i=0; i<contact->getPoints().size(); ++i) {
-            glPushMatrix();
-            glTranslatef(contact->getPoints()[i].getX(), contact->getPoints()[i].getY(), contact->getPoints()[i].getZ());
-            contact->draw();
-            glPopMatrix();
-        }
-    }
-
-	// Change the buffers
-	SDL_GL_SwapBuffers();
-}
-
-// Reshape the window
-void Scene::reshape(int width, int height) {
-    glViewport(0,0,width,height);
-	glMatrixMode(GL_PROJECTION);                           // Specify the matrix that will be modified
-	glLoadIdentity();                                      // Load the identity matrix before the transformations
-	gluPerspective(45.0, (float) width/height, 0.1f, 150.0f);
-	glMatrixMode(GL_MODELVIEW);                            // Specify the matrix that will be modified
-	glLoadIdentity();                                      // Load the identity matrix before the transformations
-}
+        glPushMatrix();
+        glTranslatef(contact->getPoint().getX(), contact->getPoint().getY(), contact->getPoint().getZ());
+        contact->draw();
+        glPopMatrix();
+    }
+
+	// Change the buffers
+	SDL_GL_SwapBuffers();
+}
+
+// Reshape the window
+void Scene::reshape(int width, int height) {
+    glViewport(0,0,width,height);
+	glMatrixMode(GL_PROJECTION);                           // Specify the matrix that will be modified
+	glLoadIdentity();                                      // Load the identity matrix before the transformations
+	gluPerspective(45.0, (float) width/height, 0.1f, 150.0f);
+	glMatrixMode(GL_MODELVIEW);                            // Specify the matrix that will be modified
+	glLoadIdentity();                                      // Load the identity matrix before the transformations
+}
diff --git a/sources/demo/Simulation.cpp b/sources/demo/Simulation.cpp
index 3e5bf783..6e63fea5 100755
--- a/sources/demo/Simulation.cpp
+++ b/sources/demo/Simulation.cpp
@@ -16,45 +16,45 @@
  * You should have received a copy of the GNU Lesser General Public License *
  * along with ReactPhysics3D. If not, see <http://www.gnu.org/licenses/>.   *
  ***************************************************************************/
-
-// Libraries
-#include "Simulation.h"
-#include "ReactDemo.h"
+
+// Libraries
+#include "Simulation.h"
+#include "ReactDemo.h"
 #include <iostream>
 
 // We want to use the ReactPhysics3D namespace
-using namespace reactphysics3d;
-
-// Constructor of the class Simulation
+using namespace reactphysics3d;
+
+// Constructor of the class Simulation
 Simulation::Simulation()
-           :world(new PhysicsWorld(Vector3D(0.0, -0.6, 0.0))), engine(world, Time(0.01)), scene(this->world) {
-    simRunning = false;
+           :world(new PhysicsWorld(Vector3D(0.0, -0.6, 0.0))), engine(world, Time(0.01)), scene(this->world) {
+    simRunning = false;
     mouseButtonPressed = false;
     nbFrame = 0;
     lastFrameTime = 0.0;
-    fps = 0.0;
-}
-
-// Destructor of the class Simulation
-Simulation::~Simulation() {
+    fps = 0.0;
+}
+
+// Destructor of the class Simulation
+Simulation::~Simulation() {
     // Delete the physics world object
-    delete world;
-}
-
-// Method to start the simulation
-void Simulation::start() {
-    // Initialisation of the OpenGL settings for the scene
-    scene.init();
-
-    // Reshape the windows for the first time
+    delete world;
+}
+
+// Method to start the simulation
+void Simulation::start() {
+    // Initialisation of the OpenGL settings for the scene
+    scene.init();
+
+    // Reshape the windows for the first time
     scene.reshape(WINWIDTH, WINHEIGHT);
 
     // Add every rigid body to the dynamic world
     for (int i=0; i<context.getNbObjects(); ++i) {
         world->addBody(context.getObject(i).getRigidBody());
     }
-
-    // Activation of the simulation
+
+    // Activation of the simulation
     simRunning = true;
 
     // Get the current time
@@ -68,11 +68,11 @@ void Simulation::start() {
     // Start the physics simulation
     pEngine->start();
 
-    //double time = 1.0;
-
-    // Main loop of the simulation
-    while(simRunning) {
-        // Check if an SDL event occured and make the apropriate actions
+    //double time = 1.0;
+
+    // Main loop of the simulation
+    while(simRunning) {
+        // Check if an SDL event occured and make the apropriate actions
         checkEvents();
 
         double time = SDL_GetTicks()/1000.0;
@@ -84,9 +84,9 @@ void Simulation::start() {
         pEngine->updateDisplayTime(Time(time));
 
         // Update the physics
-        pEngine->update();
-
-        // Display the actual scene
+        pEngine->updateCollision();
+
+        // Display the actual scene
         scene.display(context);
 
         // Compute the fps (framerate)
@@ -119,7 +119,7 @@ void Simulation::start() {
         double y2 = state2.getPosition().getY();
         double z2 = state2.getPosition().getZ();
         std::cout << "Position Cube 2: (" << x2 << ", " << y2 << ", " << z2 << ")" << std::endl;
-        std::cout << "quaternion orientation 2 : " << velocity2.getX() << ", " << velocity2.getY() << ", " << velocity2.getZ() << ", " << velocity2.getW() << ")" << std::endl;;
+        std::cout << "quaternion orientation 2 : " << velocity2.getX() << ", " << velocity2.getY() << ", " << velocity2.getZ() << ", " << velocity2.getW() << ")" << std::endl;;
         */
 
         /*
@@ -129,11 +129,11 @@ void Simulation::start() {
         }
         */
 
-    }
-}
-
-// This method checks if an events occur and call the apropriate method
-void Simulation::checkEvents() {
+    }
+}
+
+// This method checks if an events occur and call the apropriate method
+void Simulation::checkEvents() {
     SDL_Event event;                                // An SDL event
 
     // Zoom of the outside camera
@@ -142,34 +142,34 @@ void Simulation::checkEvents() {
     }
     else if(SDL_GetKeyState(NULL)[SDLK_DOWN]) {
         scene.getOutSideCamera().increaseDistance(fps);
-    }
-
-    // Check in the stack of events
-    while(SDL_PollEvent(&event)) {
-        // Check an event
-        switch(event.type) {
-            // An QUIT event occur
-            case SDL_QUIT:          simRunning = false;
-                                    break;
-
-            // A keyboard key has been pushed
-            case SDL_KEYDOWN:       // The Esc key has been pushed then we end the simulation
-                                    if (event.key.keysym.sym == SDLK_ESCAPE)
-                                    simRunning = false;
-                                    break;
-
-            // The size of the windows changed then we reshape the windows
-            case SDL_VIDEORESIZE:  scene.reshape(event.resize.w, event.resize.h);
-				                    break;
-
-			// If the mouse moved
+    }
+
+    // Check in the stack of events
+    while(SDL_PollEvent(&event)) {
+        // Check an event
+        switch(event.type) {
+            // An QUIT event occur
+            case SDL_QUIT:          simRunning = false;
+                                    break;
+
+            // A keyboard key has been pushed
+            case SDL_KEYDOWN:       // The Esc key has been pushed then we end the simulation
+                                    if (event.key.keysym.sym == SDLK_ESCAPE)
+                                    simRunning = false;
+                                    break;
+
+            // The size of the windows changed then we reshape the windows
+            case SDL_VIDEORESIZE:  scene.reshape(event.resize.w, event.resize.h);
+				                    break;
+
+			// If the mouse moved
 			case SDL_MOUSEMOTION:    if (SDL_GetMouseState(NULL, NULL)&SDL_BUTTON(1)) {
                                         // Rotation of the outSideCamera
                                         scene.getOutSideCamera().modifyHorizontalAngleRotation(event.motion.xrel, fps);
                                         scene.getOutSideCamera().modifyVerticalAngleRotation(event.motion.yrel, fps);
-                                    }
-        }
-    }
+                                    }
+        }
+    }
 }
 
 // Compute the framerate (fps) of the application
@@ -187,4 +187,4 @@ void Simulation::computeFps() {
 	 	lastFrameTime = currentTime;
 		nbFrame = 0;
 	}
-}
+}