IDPRCNV_SINGLEDISPLAYPRIORITY variable

Question

In Help there is a notice that - To optimize the display priority for very large datasets (more than 8 million elements), use the following variable: SET IDPRCNV_SINGLEDISPLAYPRIORITY=TRUE 
 
 What does this option actually do and why it is not enabled by default?

Sylvain Roberge · Accepted Answer

Hi Oto, 
 By default, the iDPR file respects the display priority of the DGN elements (same as MicroStation). When the single display priority is set to true, the viewer does not have to manage them and the display may be faster. It can be applied to dataset where there is no overlap between elements or where the overlap is not important. 
 Sylvain