Printing Each Page

After the printer object has given the document a chance to paginate itself, it calls the printout object's PrintPage member function for each page to be printed.

The process of printing out just the part of the document that belongs on the given page is similar to deciding which portion gets drawn on a scrolling window.

There are two issues to keep in mind when writing PrintPage member functions:

• Device independence. Make sure your code does not make assumptions about scale, aspect ratio, or colors. Those properties can vary between different video and printing devices, so you should remove any device dependencies from your code.
• Device capabilities. Although most video devices support all GDI operations, some printers do not. For example, many print devices, such as plotters, do not accept bitmaps at all. Others support only certain operations. When performing complex output tasks, your code should call the Windows API function GetDeviceCaps, which returns important information about the capabilities of a given output device.

See Also

• Counting Pages
• Indicating Further Pages
• Setting Print Parameters