Graphic Design File (.gdf) Definition
A schematic design file (with the extension .gdf) created with the MAX+PLUS II Graphic Editor. You can read and edit Graphic Design Files with the Quartus® Prime Block and Symbol Editors; however, the Quartus® Prime software saves the Graphic Design Files as Block Design Files (.bdf).
If the Graphic Design Files contain symbols created in the MAX+PLUS DOS software, the Quartus® Prime software can read the symbols if you update the symbols with the Update Symbol or Block command.