improved snapping

dialogs/preferencesdialog.cpp

@@ -0,0 +1,14 @@
+#include "preferencesdialog.h"
+#include "ui_preferencesdialog.h"
+
+PreferencesDialog::PreferencesDialog(QWidget *parent) :
+    QDialog(parent),
+    ui(new Ui::PreferencesDialog)
+{
+    ui->setupUi(this);
+}
+
+PreferencesDialog::~PreferencesDialog()
+{
+    delete ui;
+}