Brian,

I think there should be nothing with the DP version that's causing this. The 
issue with the automatic header setting the margins or not would be unrelated. 
If DP doesn't send the margin codes to the DPSpool file automatically, it's 
easy enough to add them.

T.R.

---

Robert,

I've had a look at the source code for DPSpool to refresh my memory as to what 
DPSpool tries to do when it receives a linefeed code. When you have specified a 
fixed LPI setting, DPSpool tells the print cursor to try to advance exactly 
that amount (i.e. 8 LPI means move the cursor down 1/8"). Internally, DPSpool 
and many other programs use "twips" as their internal measurement unit. There 
are 1440 twips in an inch, so this allows for some very fine positioning. 
Theoretically, it allows you to move the cursor around in 1/1440" increments. 
In actual practice, however, limitations of the resolution of the printer 
driver can dramatically reduce the accuracy. I think perhaps the conversion 
from twips to pixels is causing the drift you're seeing. Varying resolution or 
print-quality settings for each computer's printer driver could well be behind 
your varying results. 

Since most printers have a resolution of less than 1440 DPI, the printer driver 
has to convert the positioning from twips to pixels (DPI). If the driver on 
some of the computers is set to use, for example, 150 DPI whereas on others it 
uses 600 DPI, the accuracy of the positioning will be different. On a printer 
set to 150 DPI, each pixel equates to 9.6 twips (1440 / 150 = 9.6). But on a 
printer set to 600 DPI, each pixel equates to 2.4 twips (1440 / 600 = 2.4). 
When DPSpool tries to move the print cursor down 1/8" (for 8 LPI), that's 180 
twips (1440 / 8 = 180). At 600 DPI that's exactly 75 pixels (180 / 2.4 = 75) 
but at 150 DPI it comes out to 18.75 pixels (180 / 9.6 = 18.75) which the 
driver has to round up to 19 pixels since it can't print partial pixels. After 
enough lines, that rounding could make it start to drift the print position 
down since it's adding an extra 1/4 pixel of line height with each line printed.

I know that's a lot of math but hopefully it makes sense. It's kind of like the 
difference between trying to draw with a fine-point pen vs. a thick 
magic-marker. The finer the lines you can make, the more accurate and detailed 
your drawing will be.

Bottom line: check the default print-quality or resolution settings for each 
printer to make sure it's set as high as possible. The higher the DPI setting, 
the more accurately DPSpool (and all other programs) can print since the dots 
will be smaller and less rounding errors will creep in.

You might even try adding DPSpool's print quality code to the beginning of your 
report to try to force the printer driver to use the highest quality DPI 
setting possible. Try adding <249>QH<249>  to your report.

Of course, it's possible that I'm completely wrong in my hypothesis. But it's 
the only thing that comes to mind at the moment that could account for what 
you're seeing.

Tim Rude

  ----- Original Message ----- 
  From: Brian Hancock 
  To: [email protected] 
  Sent: Wednesday, December 16, 2009 11:16 AM
  Subject: Re: [Dataperf] DPSpool printing problem.


  Hi Tim and Robert

   

  Again I am probably way off course here, however I recollect an issue coming 
up regarding dpspool and margin and the WordPerfect header.   Since I never use 
DPSpool I am probably talking through my hat But, In the words of Lew, when 
DP2.6Y was launched on 14 Jun 2008 

   

  "[There is a bug remaining that I wanted to fix before sending this out, but 
I need your help if I am to fix it . When report output is sent to a file in 
WordPerfect format, it includes a header that sets the margins. Evidently this 
is not always wanted, or else it is not done correctly, or something. I would 
like to fix it, but I don't know what is wanted. And we need to be careful no 
to break DPSpool. Help!]

   

  I recollect Jon Ong bringing up a similar issue in 2007, I think it was 
something in 2.6e, but was not the same in 2.6x,  perhaps Jon can shed some 
light.

   

  Regards

  Brian

   


------------------------------------------------------------------------------

  From: [email protected] 
[mailto:[email protected]] On Behalf Of Robert Kendall
  Sent: Thursday, 17 December 2009 1:30 AM
  To: [email protected]
  Subject: Re: [Dataperf] DPSpool printing problem.

   

  Hi Tim,

   

  I use <213><0><8><213>.

   

  Robert

    ----- Original Message ----- 

    From: Tim Rude 

    To: [email protected] 

    Sent: Wednesday, December 16, 2009 7:52 AM

    Subject: Re: [Dataperf] DPSpool printing problem.

     

    Robert,

    Have you tried setting the lines per inch to a fixed amount?

    <213><0><Desired LPI><213>

    Tim Rude

    ----- Original Message ----- 
    From: "Robert I Kendall" <[email protected]>
    To: "Dataperfect Users Discussion Group" <[email protected]>
    Sent: Tuesday, December 15, 2009 7:46 PM
    Subject: [Dataperf] DPSpool printing problem.


    > I have multiple workstations running DPSpool to print labels from DP
    to a laser printer. When I send labels from some printers they print
    with a slightly different number of lines per inch so the bottom row of
    labels creeps off the top of the label stock (about an 1/8 of an inch to
    high).  Each workstation is running windows XP sends to the same windows
    printer and has the same printer driver. But if I look at the printer
    information diagram in dPSpool the margins for the printable area are
    different in the workstations that print incorrectly.   I can adjust the
    top margin within DPSpool so the data fits on each label but I can't get
    the lines per inch correct to be consistent on all workstations. How can
    I troubleshoot this?
    > _______________________________________________
    > Dataperf mailing list
    > [email protected]
    > http://lists.dataperfect.nl/mailman/listinfo/dataperf
    >

    _______________________________________________
    Dataperf mailing list
    [email protected]
    http://lists.dataperfect.nl/mailman/listinfo/dataperf



------------------------------------------------------------------------------


  _______________________________________________
  Dataperf mailing list
  [email protected]
  http://lists.dataperfect.nl/mailman/listinfo/dataperf
_______________________________________________
Dataperf mailing list
[email protected]
http://lists.dataperfect.nl/mailman/listinfo/dataperf

Reply via email to