screen <-> printer

Author

Message

Frank Kroeger

Posted: 07/22/2003 4:35:47

Hi,

I use TRVReportHelper to print multiple records of a report on one or more

pages.

TRVReportHelper draws the pages onto the printercanvas and as a preview to

a TImage as in one of your demos. Of course it would be nice if the preview

would look like the print. But this is not the case.

If I e.g. draw on the printercanvas in a given region of lets say 15 cm the

printer fits approx. 30 lines of text into this area. If I do the same with

the TImage it only fits 27-28 lines of text in the same region of 15 cm.

This can leed to different number of pages send to the printer, and created

on the TImage as a preview. This can be pretty annoying.

I calculate the width and height of my area in pixel with:

function mmToPixel(mm:extended;dpi:integer):integer;

begin

Result := round( (mm / 25.4) * dpi );

end;

Where for the TImage dpi = GetDeviceCaps(TImage.Canvas.Handle, LOGPIXELSX)

and for the printer dpi = GetDeviceCaps(printer.Handle, LOGPIXELSX).

I assume it might have something to do with the difference in resolution

( 96 dpi <-> 600 dpi ) but I'm not sure.

Furthermore in the TImage more characters can be fit in one line.

To make it short: A page drawn to a printercanvas does not look like a page

drawn to an imagecanvas.

Am I missing something or am I making something wrong?

Perhaps you could enlighten me.

Tia

Frank Kroeger