[poppler] [PATCH] Correctly manipulate spot colors if SPOT_NCOMPS != 4

[William Bader]

Could the '4' be a constant, maybe PROCESS_NCOMPS?

I have only ever printed with four process colors (CMYK) plus one or two spot colors (special colors for advertisers).
What happens if you print with six or eight process colors plus a spot color? Does anyone actually do that? Should the 4 be a variable instead of a constant? Does anything with more than 4 process colors become DeviceN with the first four components CMYK, so the 4 would always be a 4 for CMYK even if you had more than 4 process colors?
pdftops has to track the spot colors to set up the postscript custom colors correctly.
Regards, William

________________________________
From: poppler <poppler-bounces at lists.freedesktop.org> on behalf of Stefan Brüns <stefan.bruens at rwth-aachen.de>
Sent: Saturday, May 26, 2018 6:52 AM
To: poppler at lists.freedesktop.org
Subject: Re: [poppler] [PATCH] Correctly manipulate spot colors if SPOT_NCOMPS != 4

On Samstag, 26. Mai 2018 11:13:35 CEST Adam Reichold wrote:
> Hello again,
>
> Am 26.05.2018 um 10:55 schrieb Albert Astals Cid:
> > I don't really understand the patch, are you saying something like "the
> > code is correct, if you change it wrong it will break"? That happens in
> > lots of places ;)
>
> I guess the point is that the for loops should always start at i = 4
> (since dest[0..3] are handly outside) and should always go until NCOMPS + 4.
>
> The current code does this only if NCOMPS == 4 which is the default and
> why this currently works. But if NCOMPS != 4, the current code breaks as
> the for does not start with 4 anymore and leaves out dest[4..NCOMPS] and
> this patch fixes this.
>
> Best regards, Adam.
>

Adams assessment is completely correct.

Kind regards,

Stefan

--
Stefan Brüns  /  Bergstraße 21  /  52062 Aachen
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