/* 11.11.96. Initial release of the driver */

/* The current gs hp850 driver is meant to support all hp-color
   printers with C-RET and asymetrical resolution capabilities.
   Currently the driver supports only the the hp850 and hp855
   printers with 300x300 dpi color (with and without RET) and
   600x600dpi b/w. However, it might be possible that other printers
   like the hp890 run as well (please report any succes on other 
   printers).

   The driver _must_ be invoked with the following switches:
   gs -r600 -dBitsPerPixel=32 (see the provided cmd-files as examples)
   Furthermore, the driver supports the following switches:

   -dPapertype= 0  plain paper [default]
                1  bond paper
		2  special paper
		3  glossy film
		4  transparency film

   -dQuality=  -1 draft
                0 normal
                1 presentation [default]

   -dRetstatus= 0 C-RET off
                1 C-RET on [default]

   -dMasterGamma= 1.7 [default]

   When using the driver, be aware that printing in 600dpi involves
   processing of large amounts of data (> 188MB !). Therefore, the
   driver is not what you would expect to be a fast driver ;-)
   This is no problem when printing a full sized color page (because
   printing itself is slow), but it's really annoying if yoy print only
   text pages. Maybe I can optimize the code for text-only pages in a
   later release.
   For the time beeing, use the cdj550 device with -sBitsPerPixel=3
   for fast proof-prints. If you simply wanna print 600dpi b/w data,
   use the cdj550 device with -sBitsPerPixel=8 (or 1).
   
   Since the printer itself is slow, it may help to set the
   process-priority of the gs-process to regular or even less. On a
   486/100MHZ this is still sufficient to maintain a continuos
   data-flow.
   Note to OS/2 users: Simply put the gs-window into the background,
   or minimize it. Also make sure, that print01.sys is invoked without
   the /irq switch (great speed improvement under warp4).

   You may use -dQuality=0 or -1, however, this setting interfers in
   an undocumented way with the output of the dither routine, such
   that the midtones of colors may look ugly (I have no idea how to
   overcome this). Anyhow, printing with 600dpi is somewhat senseless
   if you don't have a high positionig precision of the print-head ;-)
   Using -dQuality=-1 makes more sense since it saves a lot of ink.

   The printer default settings compensate for dot-gain by a
   gamma-function with exponent=1.7, which is the standart in
   offset-printing. If you think that your business-graphs appear to
   pale, set -dMasterGamma=1.0.
   Furthermore, you may tweak the gammavalues independently by setting
   -dGammaValC, -dGammaValM, -dGammaValY or -dGammaValK (if not set,
   the values default to MasterGamma).

   If you wanna learn more about gamma, see:
       
       ftp://ftp.inforamp.net/pub/users/poynton/doc/colour/GammaFAQ.pdf
       
       or
       
       ftp://ftp.igd.fhg.de/pub/doc/colour/GammaFAQ.pdf

   Have fun!

	Uli

	uli@bonk.ethz.ch

*/


/* to compile, include in your makefile something like:

         DEVICE_DEVS4=cdj850.dev

   create a file cdj850.dev with the following line:

         -dev cdj850 -include page -obj gdevcd8.obj gdevpcl.obj

   locate in devs.mak the line:

         cdeskjet_=gdevcdj.$(OBJ) $(HPPCL)

   and create below the line:

         cdeskjet8_=gdevcd8.$(OBJ) $(HPPCL)

   add to the device definitions the following two lines:

        cdj850.dev: $(cdeskjet8_) page.dev
        $(SETPDEV) cdj850 $(cdeskjet8_)

   and recompile.

*/