bug fix : modified axis keeps its postition and direction now

src/main/java/fr/ill/ics/n3d/gui/AxisBuilder.java

@@ -43,16 +43,14 @@ public class AxisBuilder {
 	 */
 	public void start(Axis axis, Group parentGroup, CameraControls controls, boolean modified) {
 		this.axis = axis;
-		this.axis.setDirection(new Point3D(0, 1, 0));
-		this.axis.setPosition(controls.getCenter());
-		try {
-			this.axis.setSceneToParent(parentGroup.getLocalToSceneTransform().createInverse());
-		} catch (NonInvertibleTransformException e) {
-			e.printStackTrace();
-		}
-		this.axis.getVisualGroup().setVisible(true);
 		this.parentGroup = parentGroup;
 		if (!modified) {
+			try {
+				this.axis.setSceneToParent(parentGroup.getLocalToSceneTransform().createInverse());
+			} catch (NonInvertibleTransformException e) {
+				e.printStackTrace();
+			}
+			this.axis.getVisualGroup().setVisible(true);
 			parentGroup.getChildren().add(this.axis.getVisualGroup());
 		}
 		this.axis.getVisualGroup().setOnMousePressed(me -> {