[kde-linux] system-config-printer

[James Richard Tyrer]

Anne Wilson wrote:
> On Tuesday 03 March 2009 03:24:42 James Richard Tyrer wrote:
>> Anne Wilson wrote:
>>> On Monday 02 March 2009 12:20:59 James Richard Tyrer wrote:
>>>> What it has is a print dialog that is able to use the features
>>>>  of the printer. �Something that KDE (3|4) can not do.
>>> Absolute rubbish.  I have used kde printing for years, with two 
>>> printers that have duplexing and n-up capability.  I have no 
>>> problems whatsoever.
>> Yes, KDE-3 Supports duplexing.  N-Up has nothing to do with the 
>> printer.
>> 
>> I think that what I said was that there is no way to set the 
>> printer resolution with the KDE/Qt print dialog, and that is true.
>> 
>> Perhaps this:
>> 
>> http://home.earthlink.net/~tyrerj/kde/013.png
>> 
>> is more to the point.  You can adjust all of these parameters.
> 
> Surely printer resolution is embedded in the document?

No.  Type1 and TrueType fonts have no resolution.  A PS or PDF file can
be either raster or vector.  So, a vector PS file that consists of text
and embedded Type1 fonts has no resolution.  This is the normal way to
do it.

> Otherwise you'd have no idea what would come out of the printer.

What will come out of the printer when you print a vector file will be
the vector content rendered at the resolution of the printer.  Vector PS
files are resolution independent.  If it contains bitmaps, the
resolution of the bitmap will be modified to match the resolution of the
printer.  That is what the RIP does.

> Three people printing it would see three different documents.

No, exactly backwards, they would see the same document printed at the
resolution of their printer.  So, there will only be slightly
differences on different printers.  If the resolution was embedded in
the file, you couldn't print the same PS document on printers with
different resolutions.

> Your screenshot is of a pdf writier, which is a very different thing,
> I would have thought.
> 
I don't think so, it shows that the parameters that can be set in the PS
driver are dependent on the PPD file that it is using used.  But, back
to my printer.  It will print at three different resolutions.  What
needs to match is that the output of the RIP (the Ghostscript device in
our case) must match the resolution of the printer.  The common usage is
to print drafts at the lower resolution.  Drafts have the same font
metrics, they just don't look as good.

>> KDE-3.5 is able to do this but it is basically hard coded for just
>>  PDFs -- doesn't work for PS files.  With OO this is all done by 
>> reading a PPD file.  It is a nice interface and adding it to KDE-4
>>  would be an improvement.
>> 
>> Since this is controlled by the PPD file, you can use a different 
>> PPD file and you have different parameters to match the printer 
>> that you are using.  Basically, it works like that CUPS::Set 
>> Printer Options page.
> 
> I'm totally lost on this.  There's nothing to stop you having more 
> than one ppd file.

A PPD file indicates what the printer can do.  So, there is only one for
a printer.  However, they do contain defaults and these can be edited
(as CUPS does).

> There's nothing to stop you having more than one print queue set up 
> for one printer, based on one ppd file, with different parameters 
> set.

That was the old LP/LPR way to do it and it is basically obsolete
because it was a kludge.  Yes, when done this way, you would have a
printer named "Draft".  However, with a modern RIP and/or spooler that
can pass instructions to the printer, this is no longer necessary.

> I've not found anything that I wanted to do in printing that I can't
>  do.

Perhaps this is because you haven't looked. :-)  Do you have an inkjet
printer?  If so, I suggest that you please look.  This doesn't apply to
a laser printer since they usually print at only one resolution although
some have quality settings.

> This thread is getting nowhere,
> 
Perhaps due to your lack of technical knowledge?

To put it simply.  The PS driver in the application produces a PS file
that is, in general (but with certain exceptions) resolution
independent.  This is passed to the Raster Image Processor [RIP] which
outputs a raster image with the same resolution as the printer.  The
raster image is sent to the printer where it is printed.  If you have a
PS printer, this would work the same except that the RIP is in the printer.

In the case of printers that can print at different resolutions (most
dot matrix and ink jet printers) you can select a different printer
resolution and the RIP will then output a raster image at that resolution.

> IMO.

I see a very basic problem in your humble opinion which does not seem to
permit actual (so called constructive) criticism.  It appears to me that 
you can not resolve the idea that KDE rocks with the idea that it can be 
improved.  I see no contradiction there (things can always be improved), 
but the typical KDE fan seems to think that there is one -- that saying 
that something can be improved is the same as saying that there is 
something wrong with it and you never say that there is something wrong 
with KDE because that is "negative".  Try to see it my way that 
something which is good can still be made better and after it is made 
better, it can still be improved.  However, in the case of KDE-4 
printing, it is not good when compared to KDE-3 and needs considerable 
work to reach what I consider a basic level of usability.  To say that 
there are no issues with KDE-4 printing because it is possible (but not 
easy) to print (using CUPS) makes little sense to me.

-- 
JRT