How to build a printer

(nishantjosh.dev)

318 points | by cat-whisperer 12 hours ago ago

63 comments

  • ValdikSS 8 hours ago ago

    >penguin would shrink the result to fit its screen. >I declared A5 and Letter paper, media type stationery, and an output bin called face-up.

    You can (and should!) define exact dimensions of your screen in `media-size-supported`. It will probably be a non-standard IPP name, that's why you should define that in `media-supported` as `om_NNNmmxYYYmm` or `oe_NNNinxYYYin`

    That way you don't need to scale the incoming data, the PC will format it exactly to the dimensions of the screen.

    Both PWG Raster and Apple Raster support 1-bit-per-pixel mode (instead of 8-bit-per-pixel you use), that's why the input could be 8 times less in size. Use `print-color-mode-{supported,default}=bi-level` instead of `monochrome` for that. And also tune `urf-supported`'s `W` option, use `W1` for this case.

    The screen/dithering could be ass in 1-bit mode, see https://github.com/OpenPrinting/libcupsfilters/pull/160 where I added more dithering options (Linux-only though, Apple seems to abandon their CUPS).

    • Neywiny 7 hours ago ago

      This is why I like it here. Somebody does irrefutably incredible work outside of their comfort zone, and somebody else goes "yeah actually I was born in that zone. Moulded by it. Here's how to improve it" (in a positive way)

      • ValdikSS 7 hours ago ago

        Oh no, I wasn't, and that's definitely not my comfort zone. I mess with the printers and printing stack due to anger, not because I like it.

        It's bugs on bugs, with bugs chasing bugs! So little developers, so complex stack with 25 years of technical debt, and little community around because it's not a sexy technology to be involved in.

        That's why I have to dive deep and fix my bugs myself if I want to make it work properly as I would like it to. I also ended up making my own print server device, because China did not make a proper one for some reason for all these years.

        • lopis 3 hours ago ago

          Anger is the only valid emotion when dealing with printers.

        • edoceo 5 hours ago ago

          That's even cooler

          • quijoteuniv 3 hours ago ago

            Same feeling when family or friends ask me for help with Micros word about formatting, tables or inserting pictures in the last 25 years….

    • darkvision77 an hour ago ago

      > Use `print-color-mode-{supported,default}=bi-level` instead of `monochrome` for that

      The last time I checked (a year ago), 1bpp was suddenly supported only by Windows. IIRC, monochrome is REQUIRED, while bi-level is OPTIONAL in RFC.

      Not sure how things stand now, though. Ever since then, I've just been carrying Floyd–Steinberg dithering around.

    • cat-whisperer 7 hours ago ago

      lovely, this would save me a bunch of memory during transformation and dithering. Will do!

  • alternativeworl 7 hours ago ago

    Very cool. I was expecting to learn about the ins and outs of ink, printheads etc but instead learned "How to build a paper that acts like a printer" which turned out much more entertaining.

  • pimterry an hour ago ago

    This would be a neat API for a digital photo frame - just print photos to it and they appear on the screen.

  • kitd 2 hours ago ago

    Good article.

    One of the great things about having an open platform like the Xteink is that it should uncover loads of novel and unsatisfied use cases. Eg, this could be paired with a mobile phone to act as a secondary display much better suited to outdoor applications in bright sunlight.

  • tapia 4 hours ago ago

    In Linux it's pretty easy to create such things with cups. A while ago I did a cups backend for my Fujitsu Quaderno A4 [1]. It is super useful to be able to just open any document, in any program that supports printing, and then just "print" it to my device.

    [1] https://github.com/cristobaltapia/dpt-rp1-cups

    • IdiotSavage 3 hours ago ago

      > any program that supports printing

      Unfortunately printing support seems to go out of fashion, at least in macOS land.

      Lately I needed a quick printout of a markdown document. I could have used TextEdit for the raw text, but I wanted the styling too. Learned that neither VSCode, Xcode nor Obsidian can print. (There is a community plugin for Obsidian.)

      • rrr_oh_man 3 hours ago ago

        LOL. TIL you can’t print from VSCode.

        • maybewhenthesun 2 hours ago ago

          printing has never really been a thing from text editors I think.

          Used to be that printing a text file was just `cat myfile.txt > /dev/lp0` .

          It has been a while since I printed a plain text file, but I guess there's still a similar command available with some research.

          • voidUpdate 19 minutes ago ago

            I've done the same from a raspberry pi to a receipt printer, just piping to lp0

        • simonjgreen 2 hours ago ago

          Or Obsidian

  • yeasin-arafat an hour ago ago

    Emulating a network printer to send pages to an e-ink screen is such a clever hack. Every OS already has the print dialog built in.

  • ks2048 9 hours ago ago

    Good job, but I’m left wanting to know how to build a printer.

    • tdeck 6 hours ago ago

      If a DIY plotter would do, this site has a long list of different projects

      https://mattwidmann.net/notes/pen-plotters/

      • voxelghost 3 hours ago ago

        What if I want a cabinet sized rotating head printer that can print carbonpaper triplets, sounds a machinegun, and has LP0 ON FIRE error message

    • cat-whisperer 9 hours ago ago

      I'd say it's an eco-friendly printer

    • d--b 4 hours ago ago

      There is an open source one https://www.opentools.studio

      • zxexz 2 hours ago ago

        How is that open source? There’s not a single line of code. No CAD. Nothing. Sure, there’s a “coming soon” CrowdSupply link, which I guess is more than a KickStarter. But open source?

        • d--b 26 minutes ago ago

          Ah sorry, I thought they were already open source. They say they will open source it once they finalize the design, but yeah, not there yet.

  • e12e 4 hours ago ago

    Nice. I keep wondering if these devices would play nicer with DjVu rather than pdfs and raster formats?

    https://djvu.sourceforge.net/

  • jiehong 3 hours ago ago

    Pretty cool work! And it’s nice to see printer discovery works through the standard mDNS!

    Regarding the size of the page being sent to the printer, I remember reading that printers used to be postscript interpreters and the result of that program would be the page.

    Perhaps that would trade ram for compute, but might be more complex in the end.

  • jarboot 10 hours ago ago

    This is amazing!!! It just makes sense. And its just how you would want to use a e reader.

    • cat-whisperer 10 hours ago ago

      if it looks like a paper, it should act like a paper

  • greazy 9 hours ago ago

    I don't understand the purpose. What am I missing?

    The author "prints" to the eink display. Why not load say the pdf directly?

    • sowbug 4 hours ago ago

      I've wanted something like this for a long time to print recipes that I'm about to cook. I don't want my phone in the kitchen getting gunk on it, so I'll usually print on paper, get the gunk on the paper, and then throw it out.

      I'm not going to create a recipe PDF and load it on an e-reader. That's too much work. But I will happily press control-P on a recipe web page and select the eink display as the target.

      • greazy 19 minutes ago ago

        Right! I like this usecase very much. For uses existing software infra to perform the required task.

        I wonder now what else we've reinvented when it comes to sending data...

      • cat-whisperer 4 hours ago ago

        I am no cook, but you my friend are cooking something here

    • stdatomic 8 hours ago ago

      From the 4th line in the article:

      > But getting stuff onto it was tedious. I had to join its hotspot and open a little upload website in my browser. Yuck.

      Anyway, very creative, I like the idea a lot.

    • maybewhenthesun an hour ago ago

      I'd like my e-reader to show up as a printer, and when I print something on it it actually gets saved as a pdf on the reader. Like in the article, but multi-page pdf.

      I often do 'print to A5 pdf => copy pdf to e-reader'. Would be nice to do that in one step from any program that can print.

    • cat-whisperer 9 hours ago ago

      > I was thinking of this, but rendering PDF takes a lot out of a 400KB RAM'd device. It also needs a ton of things to actually work which the ROM can't hold.

      > Kindles have a ton of RAM, this one didn't.

      • ghostly_s 7 hours ago ago

        It's an e-reader. According to the specs it has native support for PDF.

        • mrheosuper 7 hours ago ago

          It's an esp32 MCU, even if it can somehow run the PDF render pipeline, it won't be more ideal than just accept the raw byte stream and display.

  • joshmarinacci 9 hours ago ago

    I love the concept, but I wonder why he wasn’t printing to PDF. Can this device not render PDFs?

    • ValdikSS 8 hours ago ago

      PDF is very, very complicated standard which can't be handled properly on tiny MCUs with reasonable performance and spec conformance:

          - 4 font formats
          - 9 image formats
          - blending with transparency
          - different colorspaces, each image could use its own on the page
          - different dithering algorithms, each image with its own
          - the page can have elements from another pages (global elements)
      
      This is only a small part from the top of my head.

      Common simple home printers absolutely should not accept regular PDF as an input: thanks to Apple and IETF we now have Apple Raster and PWG Raster for printers, as a part of AirPrint and IPP Everywhere/Mopria driverless printing standards, which are very similar but have slightly different options and headers. It's a simple raster input for printers specifically.

      Some companies, such as HP, invented a "raster PDF": PCLm / PCLms. Don't be confused by the name, it's a regular standard-conforming PDF which contain nothing but a full-page JPEG on each page, and don't use any other features. It's created only to be able to open "printed page" (driver output) in a standard PDF viewer on a PC for debugging or business logging needs, but otherwise it's like a regular JPEG with additional per-page metadata.

    • cat-whisperer 9 hours ago ago

      I was thinking of this, but rendering PDF takes a lot out of a 400KB RAM'd device. It also needs a ton of things to actually work which the ROM can't hold.

      Kindles have a ton of RAM, this one didn't.

    • bluGill 9 hours ago ago

      Probably not. It doesn't appear to have enough ram. I'm not sure the CPU is up to that either.

  • stavros 10 hours ago ago

    I've been seeing the Xteink a lot lately. Should I get an X3 or an X4? I don't really know why I want it, but I have an eInk addiction, so I just need it.

    • a2dam 9 hours ago ago

      I've owned all of them and the answer is the X4 Pro IMO. It has a backlight, which is the only thing I really missed on the others.

    • cat-whisperer 9 hours ago ago

      It's funny that X3 is a successor of X4. Only downside is that X4 has a USB-C port and X3 doesn't

      • stavros 9 hours ago ago

        What about the back light? Are they otherwise identical?

        • cat-whisperer 9 hours ago ago

          X3 isn't backlit, but the battery lasts 7 days. So, it's pretty good for me

    • hamaluik 8 hours ago ago

      I bought an x4 a month or so ago, zero regrets. It sounds hyperbolic but it’s finally been the thing to actually decouple me from my phone. Whenever I’m out and about, bored, I just slide it out and pick up where I left off reading last. It’s a nicer reading experience on my kobo but the portability and.. frankly charm just can’t be beat.

  • sho_hn 9 hours ago ago

    This is a fantastic idea!

  • NDlurker 8 hours ago ago

    Very cool. I'll be updating to this fork

    • cat-whisperer 8 hours ago ago

      Thanks. It's rough around the edges, so PRs are open, and there's a recipe in the repo if you want to build your own apps.

  • andyfilms1 10 hours ago ago

    We finally have PADDs from Star Trek!

  • Brian_K_White 11 hours ago ago

    Outstanding! This is so...correct.