public void __GLbegin() {
assert !bounds.isEmpty() : "no bounds defined";
begin();
if (GLHandler.ext.PixelBufferObjects.GL_isAvailable() && enabled) {
if (glPBO == null) {
glPBO = new StencilPBO(bounds, z, DebugMap._getInstance().isDebugLevelEnabled(PBOModeSTREAMenabled) ? StencilPBO.MODE.MODE_STREAM : StencilPBO.MODE.MODE_DYNAMIC);
glPBO.addListener(this);
} else /*
* in case the context switched off in-between.
*/ {
glPBO.prepareBufferObject(bounds, z, false);