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E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

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81–90 of 171 posts

Re: E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

#81

Heh that's cool. It renders the calendar as HTML and then uses selenium to open up headless chrome and screenshot it and then send the bitmap to the eink display. Clever.

there has to be a simpler way to draw a grid. there has to.

All the complexity is handled by well known tools/libraries.

I can code a selenium script to capture a screenshot in my sleep.

Often using tools your know is the best solution.

Your free to fork this and come up with a cleaner implementation. This is probably why you need a PI Zero. Smaller micro controllers can't run a full browser.

Most of these projects are just whatever can be hacked together in a weekend.

Re: E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

#82
post #35

Can’t explain why but all these E-Ink projects are so awesome and attractive to me. I’m surprised I can’t just buy a bunch of E-Ink style gizmos from some company to decorate my home and office. My wallet would be wide open to it constantly. Great work and congrats on this!

These projects have a pleasant "lo-fi zen" aspect that makes them attractive, I think. They are simple, provide value yet fade into the background without sucking your attention like some other gadgets.

I think they capture the feel of the black-and-white LCD digital watch world from before color display android everything ubiquity.

Re: E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

#83
When I was at Google I worked with the developers of the Radish project [1], which was installed all over at the time. It's amazing how far the state of the art has some since then. Aaron told me about the memory constraints - The Radish streamed data to the e-ink display's memory buffer to update, powering it on to do so only briefly, while a Pi Zero is plenty enough to render the whole display. We've come a very long way.

[1] https://developers.google.com/gdata/articles/radish

Re: E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

#84
post #59

Earlier quoted context omitted.

Cause EInk display code works nice to just ship it an image type file. So, it's gotta be rasterized before, using Chromium makes that super easy - rather than hand crafting PNG. I personally make SVG then rasterize but this isn't that terrible.

I was going down this route once, trying to use Inkscape headless. Is there a SVG-2-bitmap tool you can recommend?

Imagemagick. Does everything.

Re: E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

#86
post #84

Earlier quoted context omitted.

I was going down this route once, trying to use Inkscape headless. Is there a SVG-2-bitmap tool you can recommend?

Imagemagick. Does everything.

Somehow I missed that ImageMagick reads SVG, that is a much shorter dependency stack than selenium! Thanks

Re: E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

#88

Earlier quoted context omitted.

> Careful design, knowledge and learning is being discouraged in favour of superficial understanding, copy-pasting, tweaking-until-it-works. This is like poo-pooing amatuer woodworking and saying “people should really become an apprentice first” - no one who has the education to do careful engineering is being discouraged, the field of hardware and software is now within reach of people who just wouldn’t take on any…

no one who has the education to do careful engineering is being discouraged They are, because they think this stuff is just as good --- and it clogs the search results for those who do want to dig deeper. I often have to add "-Arduino -Maker" and a bunch of other filters to my search results to find the actually useful stuff.

This stuff IS good! It inspires people to task themselves with projects they don’t yet know how to do, and blog about what error codes they received and what they did to fix it.

Besides, how can you look down on them when you’re googling for answers instead of, you know, RTFM / getting your engineering degree?

Re: E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

#89
post #76

Earlier quoted context omitted.

Check out the Inkplate - a great e-ink platform for all these projects and more: https://inkplate.io/

Here's code that works with inkplate from a previous hn post :) https://rahulrav.com/blog/e_ink_dashboard.html Rahul got oauth2 flows working to get google calendar access.

Google Calendar provides a calendar URL which might be more convenient.

Used it in this thing: https://github.com/lawik/calendar_gadget

Re: E-Ink Magic Calendar that runs off a battery powered Raspberry Pi

#90
post #59

Earlier quoted context omitted.

Cause EInk display code works nice to just ship it an image type file. So, it's gotta be rasterized before, using Chromium makes that super easy - rather than hand crafting PNG. I personally make SVG then rasterize but this isn't that terrible.

I was going down this route once, trying to use Inkscape headless. Is there a SVG-2-bitmap tool you can recommend?

Check out https://github.com/RazrFalcon/resvg
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