The routine gNewDrawing() clears the drawing area without removing segments from the display file.
This has different effects on different output devices. On displays the whole drawing area is cleared using the most efficient method. On plotters and printers the paper is ejected or wound-on and a new drawing area or sheet is selected when the next drawing is started.
Any segments held in a display file, either hardware or software, are not deleted but flagged as being invisible. These may be made visible using the gSetSegVis() routine as required.
