Font size

[hua]

How to determine a font size that we need to specify to get them very close to the text sizes when printing in dos mode (10cpi, 12cpi, etc)?

[James Bott]

Hua,

This is from my notes file.

James

----------------------
DOS Printing Emulation

ASCII printing uses a fixed pitch font and the only one that comes with Windows is Courier New. To emulate standard ASCII 80 characters per line printing define a 12 point font as follows:

define font oFont name "Courier New" size 0,-12

To get 92 characters define a 10 point font (SIZE 0,-10).

Note, however, that DOS ASCII printing uses the same height font regradless of how many characters per line. I.E. 80 chars are the same height as 132 chars (compressed mode). Windows fonts become shorter as the point size is reduced. To maintain the same font height and get more characters per line just define the font as 12 point (SIZE 0,-12) then multiple oFont:nWidth by a correction factor. For example, to get a simulated compressed typeface (132 characters per line):

FONT oFont name "Courier New" size 0,-12

oFont:nWidth:= oFont:nWidth * (80/132)

This will give you the same number of lines per page (66) as you would get with ASCII printing.

[Enrico Maria Giordano]

oFont:nWidth:= oFont:nWidth * (80/132)

I don't think this will make any difference for the created font. That properties are just informative.

EMG

[James Bott]

Enrico,

>I don't think this will make any difference for the created font. That properties are just informative.

Well, it was quite some time ago that I used it, but I do remember it working. Have you tried it? Is, it not working now?

James

[Enrico Maria Giordano]

It seems logical that it can't work such way. Once the font is created how you can resize it only assigning a properties of a FWH class that just wraps it?

Anyway, this is a sample:

Code: Select all  Expand view

#include "FiveWin.ch"


FUNCTION MAIN()

    LOCAL oPrn, oFnt, oFnt2

    LOCAL nHStep, nVStep

    PRINT oPrn PREVIEW
        DEFINE FONT oFnt  NAME "Arial" SIZE 0, -10 OF oPrn
        DEFINE FONT oFnt2 NAME "Arial" SIZE 0, -10 OF oPrn

        oFnt2:nWidth = oFnt2:nWidth * 100

        nHStep = oPrn:nHorzRes() / 80
        nVStep = oPrn:nVertRes() / 66

        PAGE
            oPrn:Say( 0, 0, "This is a test", oFnt )
            oPrn:Say( 1 * nVStep, 0, "This is a test", oFnt2 )
        ENDPAGE
    ENDPRINT

    RELEASE FONT oFnt
    RELEASE FONT oFnt2

    RETURN NIL

EMG

[James Bott]

Enrico,

Yes, I see that in your sample it doesn't work. Here is a sample that does work. The difference must be in the way the fonts are initialized.

James

Code: Select all  Expand view

#include "fivewin.ch"
#include "report.ch"

function main()
   local oReport, oFont

   field last, first

   use test

   DEFINE FONT oFont NAME "ARIAL" SIZE 0,-12
   // oFont:nWidth:= oFont:nWidth * (80/132)   // simulate compressed font
   oFont:nWidth:= oFont:nWidth * 3

   REPORT oReport;
       TITLE  "Font Width Test";
       font oFont;
       preview

      column title "Last" data last

      end report

   activate report oReport

return nil

[Enrico Maria Giordano]

Ah, ok. The reason it works in your sample is that in TReport class the font is recreated with the new width.

EMG

[hua]

James, Enrico, thanks for the enlightening discussion

[hua]

I use GetDosFnt() to get a font size that are close to text sizes in text mode and it has serves me well all this while. But now, when one of my user prints on her Epson-LX300+, the font width and height seems to shrink. Printing on other 24-pin printers and inkjets gave me the result I expected. I don't know whether this is because LX-300+ uses 9 pin for its print head or not but I'm stumped.

Any help is appreciated.

TIA

Code: Select all  Expand view

#include "FiveWin.ch"


FUNCTION MAIN()

    LOCAL oPrn, oFnt

    PRINT oPrn PREVIEW
        oFnt := GetDosFnt(oPrn, 12)

        PAGE
            oPrn:Say( 0, 0, "This is a test", oFnt )

        ENDPAGE
    ENDPRINT

    RELEASE FONT oFnt
    RETURN NIL
//---------------------------------------------------------------------------------------
function GetDosFnt(oDev, nCPI, lBold)
  // experimental function to mimic cpi
  local oFont, nWid, nHgt, oBaseFont

  local nLogPixX := oDev:nLogPixelX()
  local nLogPixY := oDev:nLogPixelY()

  default lBold := .f.

  define font oBaseFont name "Courier New" size 0,-12

  nHgt := oBaseFont:nHeight
  if nCPI==10
     nWid := oBaseFont:nWidth*(1.3)
  elseif nCPI==12
     nWid := oBaseFont:nWidth*(1.136)
  elseif nCPI==15
     nWid := oBaseFont:nWidth*(0.953)
  elseif nCPI==20
     nWid := oBaseFont:nWidth*(0.8)
  endif
 
  oFont := TFont():New(oBaseFont:cFaceName                          ,;
                       Int(nWid*nLogPixX/72)                        ,;
                       Int(nHgt*nLogPixY/72)                        ,;    
                       .F.                                          ,;      
                       lBold                                        ,;      
                       oBaseFont:nEscapement                        ,;
                       oBaseFont:nOrientation                       ,;  
                       oBaseFont:nWeight                            ,;    
                       oBaseFont:lItalic                            ,;      
                       oBaseFont:lUnderline                         ,;  
                       oBaseFont:lStrikeOut                         ,;
                       oBaseFont:nCharSet                           ,;
                       oBaseFont:nOutPrecision                      ,;
                       oBaseFont:nClipPrecision                     ,;
                       oBaseFont:nQuality)

  oBaseFont:end()
return oFont
//----------------------------------------------------------------------------
 

[James Bott]

Hua,

It seems that either the font dimensions or the pixels per inch are being reported incorrectly by the printer driver. I would check font dimensions against another printer and also check the pixels per inch against what the documention for that printer says.

You could also try a test print by printing two lines an inch apart and then actually measure them to see what they are.

But in the end, you are probably going to just have to add a correction factor for that printer. You can get the device name and then apply the correction factor if it is that particular printer. Sometimes it is just easier to do this than to try to figure out the actual cause of the problem and you will still have to do it after you find the cause.

James

[hua]

Thanks James,

Based on your suggestion I checked out the generated font width and height (i.e. oFnt:nWidth/oFnt:nHeight). I got 14/30 for NEC P2200, 49/100 for a Canon inkjet but an odd 9/12 for the problematic Epson printer. All these values are supposed to be in pixel right?

9/12 look as though it could be the font size in points. Based on this hunch I create a font via oFont := TFont():New( "COURIER NEW", -9, -12 , .F., .F., 0, 0, 400,,,, 0, 3, 2, 1, oPrinter ). It actually solved the problem on the problematic printer but the situation got reversed, now it's the rest of the printers which has problem and only Epson prints it correctly. (BTW, I just noticed if I create a font by using TFont directly, :nWidth and :nHeight has the font size in points i.e. -9 and 12 respectively. I thought they would always be in pixel?)

Anyway, for now it seems the simplest solution for me is to just code 2 method of creating the font depending on the printer model. Would still like to get to the root of the problem though so if anyone has further info to shed it's much appreciated. Thank you