macOS Cocoa & Spot Colors

Hi,

I've been looking into creating spot colours (e.g. Pantone 032 etc) in Cocoa. I don't see any way of doing it in CoreGraphics, unless I'm being dumb and missing something?

Does anyone know how this is generally done? Just a rough point in the right direction would be appreciated!

Thanks

numero said:

I started writing a reply, but then I realized I don't really understand your question. I know what you mean by Pantone colors. Could you explain your need a little further? Are you wanting to display on screen a proximity of the Pantone color? Do you want to write the color values to a file? Or something else? The answers would help shape my response.

Click to expand...

Hi there,

Thanks for getting back to me!

What I want to do is create a PDF that contains an additional separation. That's to say, a additional spot colour. I've attached a PDF as an example which has a spot colour I've made up called "My Spot Color' (the name and RGB values could be arbitrary or from a library such as Pantone).

If you look at the screenshot from Adobe Acrobat's Output Preview tool, you can see how the spot colour appears.

If I was to print this PDF out as separations (as you would for a printing press) then I'd get 4 separations for the CMYK red colour and a single separation for the green.

Hope that makes sense!

Thanks for you help

No problem. Thanks for your time.

It looks like it's possible using PDFLib* but it costs a small fortune.

At the moment, I'm creating PDFs with spot colors by sending info to a PHP based web service of my own devising which uses TCPDF to generate the PDF I need and send me the PDF back.

Whilst that works, its a scruffy solution and relies on network connectivity. I'd like my app to be self contained and make the PDFs itself. I can do everything I need in Core Graphics *except* the spot colors. How infuriating!

I guess another solution might be to create my graphics as postscript then convert that to PDF. Again, that seems scruffy although at least it doesn't need a network connection.

Hmmm... still interested in any ideas or suggestions!






* http://www.pdflib.com/products/pdflib-family/pdflib/
** http://www.tcpdf.org

ifxpdf factory does the job. Still not free but a heck of a sight more reasonable than PDFLib!

http://ipdfdev.com/ifxpdffactory-features/

numero said:

This problem intrigues me. I may keep working on this in the background -- just to find out how the representation is made in the PDF.

Click to expand...

Just wondered whether you ever got chance to take a look at this? I stuck with my TCPDF solution in the end but I'd love to be able to support spot colors in my app.

Hah hah! Thanks for the response, albeit after a length break.

We ended up using TCPDF for a lot of stuff, and a home-grown Obj-C based PDF creation library for the simple stuff. It does seem like a major omission for Core Graphics though. I do wish Apple would add spot colour support.