CAM: Simulator: A fix for Issue #14369: Wrong drill operation simulation (#14401)

* remove redundant code

* Fix G8x drill sequence bug.  issue #14369

* fix bad simulation artifacts under Linux and QT. Issue #14369

src/Mod/CAM/PathSimulator/AppGL/DlgCAMSimulator.cpp

@@ -24,17 +24,10 @@
 
 #include "DlgCAMSimulator.h"
 #include "MillSimulation.h"
-#include <QMatrix4x4>
-#include <QScreen>
 #include <QDateTime>
 #include <QSurfaceFormat>
-#include <QMouseEvent>
-#include <QWheelEvent>
 #include <QPoint>
 
-using namespace CAMSimulator;
-using namespace MillSim;
-
 QOpenGLContext* gOpenGlContext;
 
 using namespace MillSim;
@@ -214,6 +207,8 @@ DlgCAMSimulator* DlgCAMSimulator::GetInstance()
         QSurfaceFormat format;
         format.setSamples(16);
         format.setSwapInterval(2);
+        format.setDepthBufferSize(24);
+        format.setStencilBufferSize(8);
         mInstance = new DlgCAMSimulator();
         mInstance->setFormat(format);
         mInstance->resize(800, 600);