[cups.general] ditherLine available in libcupsdriver in 1.4-1.5,future directions

[Johan Henselmans]

Op 1/23/12 6:53 PM, Michael Sweet schreef:
> On Jan 23, 2012, at 9:23 AM, Johan Henselmans wrote:
>> I have to implement some kind of halftoning in the driver I am updating,
>> and noticed that the ditherLine code that was available in the cups book
>> example was missing from 1.3, but reappeared a cupsDitherLine in the 1.4
>> cups in the driver folder, and was used in rastertopclx.
>
> The example in the CUPS book never made it into CUPS itself.
>
>> It also seemed that the rasterfilter examples in the filter folder would
>> be superseeded by the examples in the driver folder
>
> That was the plan, but there has been very little up-take in those drivers.
>
>> I just svn-ed 1.6 to see if there might be some new developments in this
>> area, and noticed that the driver folder was missing altogether.
>
> Right, it has moved to the Open Printing repository which is hosting all of the filters, backends, and support code that isn't used on Mac OS X.
>
>> I thought of perhaps using that library (libcupsdriver) for my own
>> filter, but now I am unsure.
>
> You are better off rolling your own code or, if your driver is open source, using the code in your driver directly.

I did not know that use of the source code of the filters and drivers 
would implicate to open source the printer driver that is based on it. 
Is that also the case for the sample raster filter code that is 
available in the documentation and the source code?

>
>> Can anyone tell me what the best way will be to develop printer drivers
>> for cups, going forward? (Preferably Michael...)
>
>
> In the near term, do as I outlined above.  In the long term we hope that printer drivers will no longer be needed thanks to efforts such as IPP Everywhere in the Printer Working Group and IPP-over-USB in the USB Implementers Forum.
>

I just had a look at the IPP Everywhere specs.

Would the spec not implicate that every printer has to implement it's 
own PDF/cupsRaster to raster internally, and run some kind of cups alike 
printserver internally? It seems to me a lot of duplication of effort. 
(Unless of course, every printer runs it's own freebsd/linux that would 
use the cups/openprinting work...)



> ________________________________________________________________________
> Michael Sweet, Senior Printing System Engineer, PWG Chair
>


Kind Regards,

Johan Henselmans