Electronic Ink
Tech Notes
Tech Talk
Contact Us

Tech Note: High Resolution Printing

Products: PrintOMatic Lite MX Xtra, PrintOMatic Lite Xtra 1.6.5, PrintOMatic MX Xtra, PrintOMatic Xtra 1.6.5
Platforms: all

How can I print at high resolution (300 DPI or more) using PrintOMatic or PrintOMatic Lite?

Printing High Resolution Text

Text strings and text field cast members printed using the append() or drawText() commands will always print at the current resolution of the printer in both Lite and Full versions of the Xtra. However, Rich Text members only print as 72DPI bitmaps. If you want high resolution text output, you need to use text strings or text field cast members. For more information, read our tech note on Text Members and PrintOMatic.

Printing High Resolution Graphics

Printing graphics (specifically, bitmap cast members) at high resolution is trickier than printing high resolution text. PrintOMatic Lite gives you very little control over the destination size of a printed bitmap, so we recommend using the FULL version of the Xtra for printing high resolution bitmaps.

The following information about printing graphics at high resolution applies to the FULL version of PrintOMatic only. We don’t recommend using PrintOMatic Lite to print high resolution graphics.

There are two parts to the high resolution printing problem: the first is getting around the Director cast’s limitation of 72DPI by importing large images. The second is scaling those large cast members down on the printed page to increase their printed resolution.

The first problem is that Director knocks the resolution of imported images that contain DPI information down to a standard 72DPI when you import them into the cast. The way around this is to save your images at 72DPI, but make them very large.

For example, if you want a 1-inch by 1-inch graphic at 300DPI, then you should save it at (roughly) 4 inches by 4 inches at 72 DPI instead. When you import it into the Director cast, you should end up with a bitmapped cast member that is 288 x 288 pixels.

You need to use the drawPicture command to print bitmap cast members members at high resolution. With drawPicture, you can specify a small destination rectangle, which will "shrink" your image. When the image is "shrunk" on the page, it still keeps all of its original pixels. So the result of "shrinking" an image on the output page is to increase its resolution.

Continuing with the example above, if you have a cast member that is 288 x 288 pixels you’ll need to print it at 1 inch by 1 inch (72 x 72 points) to get output of (roughly) 300 DPI (actually 288 DPI). You control the output size by modifying the destRect parameter of the drawPicture command.

drawPicture doc, member "myBigImage", Rect(0,0,72,72)

Because the destination rect is 72x72 points (1 inch by 1 inch), but your image is 288x288 pixels, you’ll end up with a 288 DPI image in the upper left corner of the page.

Print this Tech Note Print this Technical Note

©1994-2018 Electronic Ink. All rights reserved.