This function was introduced in Quick PDF Library version 7.12.
For detailed page layouts this function can be called before a group of drawing commands. The page layout commands will then be buffered until a matching call to the EndPageUpdate function.
function TDebenuPDFLibrary1511.BeginPageUpdate: Integer;
Function DebenuPDFLibrary1511.PDFLibrary::BeginPageUpdate As Long
int DPLBeginPageUpdate(int InstanceID)