HOWTO: Simulating CreatePatternBrush() on a High-Res Printer

ID: Q74793

The information in this article applies to:

Microsoft Windows Software Development Kit (SDK) 3.1
Microsoft Win32 Application Programming Interface (API), used with:
- Microsoft Windows 95

SUMMARY

When a pattern brush is used to fill an area of the page on the printer, the printer's high resolution will cause a fine pattern to lose definition and appear as a shade of gray.

Brushes that are created with the CreatePatternBrush() function are eight pixels by eight pixels (8 x 8 pixels) in size. On a 300 dots-per-inch (dpi) laser printer, the pattern will be 0.027 inches wide.

To create a pattern that gives similar effects on the screen as on the printer, it is necessary to compare the screen resolution to the printer resolution, and to compensate for the differences.

For example, if the video display is 100 dpi (typical of a VGA), and the printer is 300 dpi (a typical laser printer), the bit must be three times larger in each direction. The following compares a screen bitmap and a printer bitmap:


   10101010          111000111000111000111000
   01010101          111000111000111000111000
   10101010          111000111000111000111000
   01010101          000111000111000111000111
   10101010          000111000111000111000111     and so forth
   01010101          000111000111000111000111
   10101010          111000111000111000111000
   01010101          111000111000111000111000
                     111000111000111000111000
    Video            000111000111000111000111
                     000111000111000111000111
                     000111000111000111000111
                     111000111000111000111000
                     111000111000111000111000
                     111000111000111000111000
                     000111000111000111000111
                     000111000111000111000111
                     000111000111000111000111
                     111000111000111000111000
                     111000111000111000111000
                     111000111000111000111000
 
                             Printer

However, since the pattern brush is always 8 x 8 pixels, a different approach must be used when printing:

Use the StretchBlt() function to create, from the video bitmap, the 24 x 24 pixel bitmap for the printer.

Manually "tile" this bitmap into the region to be painted.

Additional query words: 3.00 3.10 4.00 win16sdk

Keywords : kbWinOS95 kbDSupport kbSDKWin16
Version : WINDOWS:3.1,95; winnt:
Platform : WINDOWS winnt
Issue type : kbhowto