World: r3wp

Are there anything special, you need in postscript.r?

I was afraid of messing with it, since only a single error, such 
as leaving a standard postscript command out or putting another one 
in, caused some printers to stop working with it.

There is a bug with printing multiple pages on certain HP printers. 
After the first page, some char is missing, that causes it to wait 
until you press the Online button or page feed button. I really would 
like that to be fixed. The work-around is to print to a file and 
have it printed using Printfile under Windows.

And I also badly need bitmap support :-)

Ok, I try to stick to the standard and keep things simple.

well, I tried standard commands, but it seems that printers and postscript 
is like HTML and webbrowsers, unfortunately.

damn

it would be wise to look at demo postscript files from around the 
net and see what they do. try to print them on various printers.

When you had problem, did you try changing the %%Pages and %%Page 
lines in the ps-doc?

had very limited time to test and don't remember

ok

it was a panic situation .:-)

furthermore, when printing with LP under OSX, produces different 
margins and scales than LP under Linux. so that's fun.

Added PageSize and images to the PostScript dialect. There seem to 
be a problem with jpg!?
Henrik, try this:

do http://home.tiscali.dk/john.niclasen/postscript/postscript.r

write %imagetest.ps postscript [page [translate 100 600 scale 72 
72 image logo.gif translate 100 500 scale 144 144 image logo.gif 
translate 100 300 scale 288 288 image logo.gif]]

Then view or print the file imagetest.ps

This gives a result, that I can't view on my Mac for some reason:


write %imagetest.ps postscript [page [translate 100 400 scale 72 
72 image http://www.rebol.com/view/palms.jpg]]

Any suggestions?

preview.app is unfortunately also half demented :-(

ghostscript is better to reference against

and I can't test right now as I don't have the printer set up

I will test as soon as possible

I have problem viewing the test with jpg here. It can't convert it 
to a viewing format (prob. PDF). Can you test the ghostscript viewer?

will take 30 mins to set up. hang on.

Documentation is here:
http://home.tiscali.dk/john.niclasen/postscript/postscript.html

any image formats that you've tested that works?

gif and bmp

so it converts it to image! before feeding it to postscript dialect?

Hm, maybe it has something to do with the size of the image. I saved 
logo.gif as %logo.bmp and it works. If I save that palms.jpg as %palms.bmp, 
it doesn't work.

afk, 30 mins

Yes, images are handled as REBOL image! types. If the dialect is 
given a file! or url!, it'll load the image. It can also take a word!, 
which is the image. It then convert the image/rgb to base-16 and 
put it in the ps-file.

So images in postscript files take up a lot of space! Most people 
knows this already. I tried to put a 100k png image in a postscript 
file, and it then was > 11MB.

wow

what about 2-colored GIFs?

I"ve always converted images to eps before including them. Never 
used raw image data.

That will work with vector images, but not necessarily pictures - 
EPS would have the same problems as Postscript.

AFAIK, EPS is PS without page handling information

Yes. I use things like imagemagick to do the conversion for me from 
binary image ( whatever format ) to eps.

But if the image is big, it remains big ... not that it's a problem 
because it's being dumped to a printer.

it's a problem for speed, but perhaps there really is no way around 
it

exactly because postscript can not handle gif, tiff, png, jpeg etc.

but I was wondering if it accepts some kind of 2 or 4 bit format 
for smaller data sizes. the images I need to use are usually of low 
color.

whereas LaTeX can use jpeg.

well, LaTeX is converted to postscript, so maybe the end result is 
the same.

Here's an article on coverting a jpeg to image using postscript functions 
http://www.tinaja.com/glib/jpg2pdf.pdf

This with large printfiles, it's the same, that happens, if you print 
text using a font, that the printer doesn't know. Everything is converted 
to image data, and one page can be several MB.

The image problem seems to be related to size. I tried to make a 
little image entirely in REBOL, and I can see that. Making a larger 
image, and Preview under OSX can't convert it to PDF. I would like 
to know, if my example above with palms.jpg can be printed on paper.

If the image is 11mb, the printer would need more memory than that 
to print it, assuming the Postscript has no logic bugs that would 
prevent the printer from rendering the image at all.

I have problem with an image like in this example:

do http://home.tiscali.dk/john.niclasen/postscript/postscript.r
img: to-image layout [box 20x20 red box blue]

write %imagetest.ps postscript [page [translate 100 400 scale 72 
72 image img]]


Try print (or view) the imagetest.ps file. Do you also get an error?

ERROR: /rangecheckESP Ghostscript 815.04: Unrecoverable error, exit 
code 1
 in --string--
Operand stack:
   picstr   70560
Execution stack:

   %interp_exit   .runexec2   --nostringval--   --nostringval--   --nostringval-- 
     2   %stopped_push   --nostringval--   --nostringval--   --nostringval-- 
     false   1   %stopped_push   1   3   %oparray_pop   1   3   %oparray_pop 
     1   3   %oparray_pop   1   3   %oparray_pop   .runexec2   --nostringval-- 
     --nostringval--   --nostringval--   2   %stopped_push   --nostringval--
Dictionary stack:

   --dict:1125/1686(ro)(G)--   --dict:0/20(G)--   --dict:108/200(L)--
Current allocation mode is local

That's what I get

Geomol, I wonder if GS can output it's stacks for debugging purposes. 
would that be useful to you?

Since postscript is a printer language, it can print the stacks if 
it encounters an error.