To determine if you are printing to the printer, you need to check inside the draw routine for every drawable view where you expect printing to make a difference. The TPrintingFlagSnapshot class gives you access to the printing flag in the Grafport.
The following example shows how to check for printing:
TPrintingFlagSnapshot areWePrinting(port); // port is Grafport passed to the draw call. // Then every place you need to know ... if (areWePrinting.IsPrintingPort()) { // Write the code to use when printing here } else { // Write the code when not printing here }