diff --git a/window.c b/window.c
index 22c1877..ca3a28b 100644
--- a/window.c
+++ b/window.c
@@ -137,7 +137,7 @@ void init(void) {
 		bsound = Mix_LoadWAV("./space.wav");
 	if (Mix_PlayChannel(-1, bsound, 0) < 0)
 		fprintf(stderr, "Mix_PlayChannel: %s\n", Mix_GetError());
-	
+
 	// create all spheres.
 	_sun = mkSphere(12, 12);  /*ça fait 12x12x2 triangles !*/
 	for(i = 0; i < 18; ++i) {
@@ -180,7 +180,7 @@ void init(void) {
 
 	// set texture to an object id and set all options.
 	setTexId(_sun, sun_id);
-	if(_use_tex) 
+	if(_use_tex)
 		enableSurfaceOption(_sun, SO_USE_TEXTURE);
 	if(_use_lighting)
 		enableSurfaceOption(_sun, SO_USE_LIGHTING);
@@ -188,16 +188,16 @@ void init(void) {
 	for(i = 0; i < 18; ++i) {
 		setTexId(_moon[i], moon_id[i]);
 		disableSurfaceOption(_moon[i], SO_USE_COLOR);
-		if(_use_tex) 
+		if(_use_tex)
 			enableSurfaceOption(_moon[i], SO_USE_TEXTURE);
-		if(_use_lighting) 
+		if(_use_lighting)
 			enableSurfaceOption(_moon[i], SO_USE_LIGHTING);
 		if (i < 9) {
 			setTexId(_planet[i], id[i]);
 			disableSurfaceOption(_planet[i], SO_USE_COLOR);
-			if(_use_tex) 
+			if(_use_tex)
 				enableSurfaceOption(_planet[i], SO_USE_TEXTURE);
-			if(_use_lighting) 
+			if(_use_lighting)
 				enableSurfaceOption(_planet[i], SO_USE_LIGHTING);
 		}
 	}
@@ -281,6 +281,17 @@ static void goto_obj(float * mvMat) {
 	}
 }
 
+void draw_object(float * nmv, float * projMat, surface_t * obj,
+		float ma, float mx, float my, float mz,
+		float tx, float ty, float tz, float s,
+		float ra, float rx, float ry, float rz) {
+	rotate(nmv, ma, mx, my, mz); // orbit movement
+	translate(nmv, tx, ty, tz);
+	scale(nmv, s, s, s);
+	rotate(nmv, ra, rx, ry, rz); // rotation
+	transform_n_raster(obj, nmv, projMat);
+}
+
 /*!\brief la fonction appelée à chaque display. */
 void draw(void) {
 	static double t0 = 0, t, dt;
@@ -307,217 +318,114 @@ void draw(void) {
 
 	// SUN
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, (_r / 24.5f), 0.0f, 1.0f, 0.0f);
-	translate(nmv, 0.0f, 1.0f, 0.0f);
-	scale(nmv, 2,2,2);
-	transform_n_raster(_sun, nmv, projMat);
-
+	draw_object(nmv, projMat, _sun, _r/24.5f, 0, 1, 0, 0, 1, 0, 2, 0, 0, 0, 0);
 	// MERCURY
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, (_a / 87.97f), 0.0f, 1.0f, 0.0f); // orbit mouvement
-	translate(nmv, 4.2f, 1.0f, 0.0f);
-	scale(nmv, (1/227.0f) * 12.0f, (1/227.0f) * 12.0f, (1/227.0f) * 12.0f);
-	rotate(nmv, (_r / 59.0f), 0.0f, 1.0f, 0.0f); // rotation
-	transform_n_raster(_planet[0], nmv, projMat);
+	draw_object(nmv, projMat, _planet[0], _a/87.97f, 0, 1, 0, 4.2f, 1, 0, (1/227.0f)*12, _r/59.0f, 0, 1, 0);
 
 	// VENUS
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, (_a / 224.7f), 0.0f, 1.0f, 0.0f); // orbit mouvement
-	translate(nmv, 7.9f, 1.0f, 0.0f);
-	scale(nmv, (1/113.0f) * 12.0f, (1/113.0f) * 12.0f, (1/113.0f) * 12.0f);
-	rotate(nmv, (_r / 243.75f), -0.1773f, -1.0f, 0.0f); // rotation anti-clockwise
-	transform_n_raster(_planet[1], nmv, projMat);
+	draw_object(nmv, projMat, _planet[1], _a/224.7f, 0, 1, 0, 7.9f, 1, 0, (1/113.0f)*12, _r/243.75f, -0.1773f, -1, 0);
 
 	// EARTH
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, (_a / 365.2425f), 0.0f, 1.0f, 0.0f);
-	translate(nmv, 10.0f, 1.0f, 0.0f);
-	scale(nmv, (1/108.0f) * 12.0f, (1/108.0f) * 12.0f, (1/108.0f) * 12.0f);
-	rotate(nmv, _r, -0.234f, 1.0f, 0.0f);
-	transform_n_raster(_planet[2], nmv, projMat);
+	draw_object(nmv, projMat, _planet[2], _a/365.2425f, 0, 1, 0, 10.0f, 1, 0, (1/108.0f)*12, _r, -0.234f, 1, 0);
 
 	// Moon
-	translate(nmv, 4.0f, 0.0f, 0.0f);
-	scale(nmv, (1/5.0f) , (1/5.0f), (1/5.0f));
-	transform_n_raster(_moon[0], nmv, projMat);
+	draw_object(nmv, projMat, _moon[0], 1, 0, 0, 0, 4.0f, 0, 0, (1/5.0f), 1, 0, 0, 0);
 
 	// MARS
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, (_a / 686.98f), 0.0f, 1.0f, 0.0f);
-	translate(nmv, 15.2f, 1.0f, 0.0f);
-	scale(nmv, (1/208.0f) * 12.0f, (1/208.0f) * 12.0f, (1/208.0f) * 12.0f);
-	rotate(nmv, _r / 1.0416f, -0.252f, 1.0f, 0.0f);
-	transform_n_raster(_planet[3], nmv, projMat);
+	draw_object(nmv, projMat, _planet[3], _a/686.98f, 0, 1, 0, 15.2f, 1, 0, (1/208.0f)*12, _r/1.0416f, -0.252f, 1, 0);
 
 	memcpy(cpy, nmv, sizeof cpy);
 
 	// Phobos
-	rotate(nmv, _r * 4.3f, 0.0f, 0.1f, 0.0f);
-	translate(nmv, 10.0f, 1.0f, 0.0f);
-	scale(nmv, (1/5.0f), (1/5.0f), (1/5.0f));
-	transform_n_raster(_moon[1], nmv, projMat);
+	draw_object(nmv, projMat, _moon[1], _r*4.3f, 0, 0.1f, 0, 10.0f, 0, 0, (1/5.0f), 0, 0, 0, 0);
 
 	// Deimos
-	rotate(cpy, _r / 1.5f, 0.0f, 0.1f, 0.0f);
-	translate(cpy, 25.0f, 1.0f, 0.0f);
-	scale(cpy, (1/6.0f), (1/6.0f), (1/6.0f));
-	transform_n_raster(_moon[2], cpy, projMat);
+	draw_object(cpy, projMat, _moon[2], _r/1.5f, 0, 0.1f, 0, 25.0f, 0, 0, (1/6.0f), 0, 0, 0, 0);
 
 	// JUPITER
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, _a / (12 * 365.2425f), 0.0f, 1.0f, 0.0f);
-	translate(nmv, 30.0f, 1.0f, 0.0f);
-	scale(nmv, (1/9.7f) * 12.0f, (1/9.7f) * 12.0f, (1/9.7f) * 12.0f);
-	rotate(nmv, _r / 0.416f, -0.031f, 1.0f, 0.0f);
-	transform_n_raster(_planet[4], nmv, projMat);
-
+	draw_object(nmv, projMat, _planet[4], _a/(12 * 365.2425f), 0, 1, 0, 30.0f, 1, 0, (1/9.7f)*12, _r/0.416f, -0.031f, 1, 0);
+	
 	memcpy(cpy, nmv, sizeof cpy);
 
 	// Io
-	rotate(nmv, _r * 3.0f, 0.0f, 0.1f, 0.0f);
-	translate(nmv, 3.0f, 0.0f, 0.0f);
-	scale(nmv, (1/11.2f), (1/11.2f), (1/11.2f));
-	transform_n_raster(_moon[3], nmv, projMat);
-
-	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[3], _r*3.0f, 0, 0.1f, 0, 3.0f, 0, 2, (1/11.2f), 0, 0, 0, 0);
 
 	// Europa
-	rotate(nmv, _r / 2.0f, 0.0f, 0.1f, 0.0f);
-	translate(nmv, 4.0f, 0.0f, 0.0f);
-	scale(nmv, (1/13.2f), (1/13.2f), (1/13.2f));
-	transform_n_raster(_moon[4], nmv, projMat);
-
 	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[4], _r/2.0f, 0, 0.1f, 0, -4.0f, 0, -1, (1/13.2f), 0, 0, 0, 0);
 
 	// Ganymede
-	rotate(nmv, _r / 3.0f, 0.0f, 0.1f, 0.0f);
-	translate(nmv, 5.0f, 0.0f, 0.0f);
-	scale(nmv, (1/9.0f), (1/9.0f), (1/9.0f));
-	transform_n_raster(_moon[5], nmv, projMat);
-
 	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[5], _r/3.0f, 0, 0.1f, 0, -5.0f, 0, -1.5f, (1/9.0f), 0, 0, 0, 0);
 
 	// Callisto
-	rotate(nmv, _r / 5.0f, 0.0f, 0.1f, 0.0f);
-	translate(nmv, 6.0f, 0.0f, 0.0f);
-	scale(nmv, (1/10.0f), (1/10.0f), (1/10.0f));
-	transform_n_raster(_moon[6], nmv, projMat);
+	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[6], _r/5.0f, 0, 0.1f, 0, 6.0f, 0, -2.5f, (1/10.0f), 0, 0, 0, 0);
 
 	// SATURN
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, _a / (30 * 365.2425f), 0.0f, 1.0f, 0.0f);
-	translate(nmv, 50.4f, 1.0f, 0.0f);
-	scale(nmv, (1/11.4f) * 12.0f, (1/11.4f) * 12.0f, (1/11.4f) * 12.0f);
-	rotate(nmv, _r / 0.4583f, -0.267f, 1.0f, 0.0f);
-	transform_n_raster(_planet[5], nmv, projMat);
+	draw_object(nmv, projMat, _planet[5], _a/(30 * 365.2425f), 0, 1, 0, 50.4f, 1, 0, (1/11.4f)*12, _r/0.4583f, -0.267f, 1, 0);
 
 	memcpy(cpy, nmv, sizeof cpy);
 
 	// Enceladus
-	rotate(nmv, _r * 5.0f, 0.0f, 0.1f, 0.0f);
-	translate(nmv, 2.0f, 0.0f, 0.0f);
-	scale(nmv, (1/20.0f), (1/20.0f), (1/20.0f));
-	transform_n_raster(_moon[7], nmv, projMat);
-
-	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[7], _r*5.0f, 0, 0.1f, 0, 2.0f, 0, -2.0f, (1/20.0f), 0, 0, 0, 0);
 
 	// Dione
-	rotate(nmv, _r * 4.0f, 0.0f, 0.01f, 0.0f);
-	translate(nmv, 3.0f, 0.0f, 0.0f);
-	scale(nmv, (1/18.0f), (1/18.0f), (1/18.0f));
-	transform_n_raster(_moon[8], nmv, projMat);
-
 	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[8], _r*4.1f, 0, 0.1f, 0, -3.0f, 0, -0.5f, (1/18.0f), 0, 0, 0, 0);
 
 	// Rhea
-	rotate(nmv, _r * 3.0f, 0.0f, 0.01f, 0.0f);
-	translate(nmv, 4.0f, 0.0f, 0.0f);
-	scale(nmv, (1/15.0f), (1/15.0f), (1/15.0f));
-	transform_n_raster(_moon[9], nmv, projMat);
-
 	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[9], _r*3.2f, 0, 0.1f, 0, 4.0f, 0, -2.5f, (1/15.0f), 0, 0, 0, 0);
 
 	// Titan
-	rotate(nmv, _r / 4.0f, 0.0f, 0.01f, 0.0f);
-	translate(nmv, 6.0f, 0.0f, 0.0f);
-	scale(nmv, (1/10.0f), (1/10.0f), (1/10.0f));
-	transform_n_raster(_moon[10], nmv, projMat);
-
 	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[10], _r/4.3f, 0, 0.1f, 0, -6.0f, 0, -5.2f, (1/10.0f), 0, 0, 0, 0);
 
 	// Iapetus
-	rotate(nmv, _r / 6.0f, 0.0f, 0.01f, 0.0f);
-	translate(nmv, 7.0f, 0.0f, 0.0f);
-	scale(nmv, (1/14.0f), (1/14.0f), (1/14.0f));
-	transform_n_raster(_moon[11], nmv, projMat);
+	memcpy(nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[11], _r/6.3f, 0, 0.1f, 0, 7.0f, 0, -3.2f, (1/14.0f), 0, 0, 0, 0);
 
 	// URANUS
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, _a / (84 * 365.2425f), 0.0f, 1.0f, 0.0f);
-	translate(nmv, 65.0f, 1.0f, 0.0f);
-	scale(nmv, (1/26.8f) * 12.0f, (1/26.8f) * 12.0f, (1/26.8f) * 12.0f);
-	rotate(nmv, _r / 0.7083f, -0.978f, 0.0f, 0.0f);
-	transform_n_raster(_planet[6], nmv, projMat);
+	draw_object(nmv, projMat, _planet[6], _a/(84 * 365.2425f), 0, 1, 0, 65.0f, 1, 0, (1/26.8f)*12, _r/0.7083f, -0.978f, 0, 0);
 
 	memcpy(cpy, nmv, sizeof cpy);
 
 	// Ariel
-	rotate(nmv, _r , 0.01f, 0.0f, 0.0f);
-	translate(nmv, 0.0f, 3.0f, 0.0f);
-	scale(nmv, (1/20.0f), (1/20.0f), (1/20.0f));
-	transform_n_raster(_moon[12], nmv, projMat);
-
-	memcpy (nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[12], _r, 0.01f, 0, 0, 0, 3.0f, -2.2f, (1/20.0f), 0, 0, 0, 0);
 
 	// Umbriel
-	rotate(nmv, _r / 2.0f, 0.01f, 0.0f, 0.0f);
-	translate(nmv, 0.0f, 4.0f, 0.0f);
-	scale(nmv, (1/20.0f), (1/20.0f), (1/20.0f));
-	transform_n_raster(_moon[13], nmv, projMat);
-
 	memcpy (nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[13], _r/2.0f, 0.01f, 0, 0, 0, -4.0f, -1.2f, (1/20.0f), 0, 0, 0, 0);
 
 	// Titania
-	rotate(nmv, _r / 3.0f, 0.01f, 0.0f, 0.0f);
-	translate(nmv, 0.0f, 5.0f, 0.0f);
-	scale(nmv, (1/17.0f), (1/17.0f), (1/17.0f));
-	transform_n_raster(_moon[14], nmv, projMat);
-
 	memcpy (nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[14], _r/5.0f, 0.01f, 0, 0, 0, 5.0f, 0, (1/17.0f), 0, 0, 0, 0);
 
 	// Oberon
-	rotate(nmv, _r / 5.0f, 0.01f, 0.0f, 0.0f);
-	translate(nmv, 0.0f, 6.0f, 0.0f);
-	scale(nmv, (1/17.0f), (1/17.0f), (1/17.0f));
-	transform_n_raster(_moon[15], nmv, projMat);
+	memcpy (nmv, cpy, sizeof nmv);
+	draw_object(nmv, projMat, _moon[15], _r/7.0f, 0.01f, 0, 0, 0, 6.0f, -4.4f, (1/17.0f), 0, 0, 0, 0);
 
 	// NEPTUNE
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, _a / (165 * 365.2425f), 0.0f, 1.0f, 0.0f);
-	translate(nmv, 75.0f, 1.0f, 0.0f);
-	scale(nmv, (1/27.7f) * 12.0f, (1/27.7f) * 12.0f, (1/27.7f) * 12.0f);
-	rotate(nmv, _r / 0.6f, -0.283f, 1.0f, 0.0f);
-	transform_n_raster(_planet[7], nmv, projMat);
+	draw_object(nmv, projMat, _planet[7], _a/(165 * 365.2425f), 0, 1, 0, 75.0f, 1, 0, (1/27.7f)*12, _r/0.6f, -0.283f, 1.0f, 0);
 
 	// Triton
-	rotate(nmv, _r / 5.0f, 0.0f, 0.01f, 0.0f);
-	translate(nmv, 3.0f, 0.0f, 0.0f);
-	scale(nmv, (1/10.0f), (1/10.0f), (1/10.0f));
-	transform_n_raster(_moon[16], nmv, projMat);
+	draw_object(nmv, projMat, _moon[16], _r/5.0f, 0, 0.01f, 0, 3.0f, 0.0f, 0.0f, (1/10.0f), 0, 0, 0, 0);
 
 	// PLUTO
 	memcpy(nmv, mvMat, sizeof nmv); /* copie mvMat dans nmv */
-	rotate(nmv, _a / (248 * 365.2425f), 0.0f, 1.0f, 0.0f);
-	translate(nmv, 85.4f, 1.0f, 0.0f);
-	scale(nmv, (1/500.0f) * 12.0f, (1/500.0f) * 12.0f, (1/500.0f) * 12.0f);
-	rotate(nmv, _r / 6.4, -0.119f, 1.0f, 0.0f);
-	transform_n_raster(_planet[8], nmv, projMat);
+	draw_object(nmv, projMat, _planet[8], _a/(248 * 365.2425f), 0, 1, 0, 85.0f, 1, 0, (1/500.7f)*12, _r/6.4f, -0.119f, 1.0f, 0);
 
 	// Charon
-	rotate(nmv, _r / 5.0f, 0.0f, 0.01f, 0.0f);
-	translate(nmv, 3.0f, 0.0f, 0.0f);
-	scale(nmv, (1/13.0f), (1/13.0f), (1/13.0f));
-	transform_n_raster(_moon[16], nmv, projMat);
+	draw_object(nmv, projMat, _moon[17], _r/5.0f, 0, 0.01f, 0, 3.0f, 0.0f, 0.0f, (1/13.0f), 0, 0, 0, 0);
 
 	/* déclarer qu'on a changé (en bas niveau) des pixels du screen  */
 	gl4dpScreenHasChanged();