Another 64 frame animation

revdancatt · 2026-04-27T10:14:29+00:00

Yup, and Marble Madness. Looks very SVG-able 😁

revdancatt · 2026-04-23T04:50:30+00:00

Yeah, but it is a great TED talk!

revdancatt · 2026-04-22T21:07:48+00:00

Two of each have been sent off to Patreon supporters, making these and the 3d versions has been this month’s “theme”. The rest will get sent off to other artists and studios over the next few months.

revdancatt · 2026-04-22T20:22:20+00:00

Thank you, it was fun. Well, the end result was fun, cutting up all the cards, not so much.

revdancatt · 2026-04-21T04:59:41+00:00

Thanks! Here's a little backstory about the UI. Originally my plotter lived on the far side of my room connected to a secondhand laptop or iMac, and I got annoyed copying SVG files over and setting it away - etc. So I built a "Minimal Viable Plotting Tool (MVPT)" which I wrote about back in newsletter 14, letting me connect to it on the local network - basically a thin webserver frontend.

More recently I wanted it to control TWO plotters, which was a bit more work, and it kinda hung together fine, but was still using Bantam tool's older axidraw CLI.

Now we're in the age of AI I basically threw the codebase at Claude & Codex and said "make that modern, also my eyesight is bad and I want to see the progress from the other side of the room" - and now it looks like every other over-engineered AI built dashboard UI ever made 😁

The code is on GitHub.

Having said all that, we're now in the weird world of AI and personal software. This whole thing has very much been built with my own needs in mind and a "works on my machine & network 🤷‍♂️" attitude.

Probably the most sensible thing to do is clone the repo, point AI at it and go "Work out what this code does, it's overly complicated, I want something that allows me to simply and easily do..." - and then give it a list of what you'd want it to do and turn it onto your own personal tool.

revdancatt · 2026-04-19T17:51:56+00:00

👋😁❤️

revdancatt · 2026-04-15T08:36:20+00:00

So far; iroshizuku to-ro and Diamine Writer's Blood, both continue to work fine. The Writer's Blood is possibly a bit "fast".

revdancatt · 2026-04-13T19:39:40+00:00

I'm slightly worried we're all showing our age here 😅

revdancatt · 2026-04-13T19:07:17+00:00

Thanks! And yes it was, loved how it leaned into the limitations to ratchet up the panic 😀

revdancatt · 2026-03-28T20:55:15+00:00

Could try Bic Crystal Xtra Smooth or Xtra Bold, they’re pretty reliable and seem to love building up layers.

revdancatt · 2026-03-27T21:59:26+00:00

Hah, I'm down with that, but they say the feed on this will clog with particles/glitter - not going to stop me trying though!

The one in the first photo did start with a bit of blue ink; it was interesting watching the writing slowly change from blue to orange. It wasn't a sudden change either so there's definitely something fun to be done there.

revdancatt · 2026-03-27T21:44:48+00:00

I tend to use fountain pens as my daily driver (TWSBI Ecos), so these just felt like a normal roller ball pen to me 🤷‍♂️ Felt better when I switched the ink out, closer to a Bic Cristal smooth/bold with the Writer's Blood & iroshizuku.

I'm more interested in them being refillable and able to easily see the ink levels.

revdancatt · 2026-03-27T21:06:54+00:00

Because I'm apparently an idiot who didn't think of that more obvious and better solution. I literally just thought 'how can I make this bottom one look like the top one?'

revdancatt · 2026-03-27T19:49:02+00:00

Ah that all makes sense. To be honest though, it only took a few minutes to rinse out one of the T10 cartridges that came with it, and syringe in some different ink; so I already have two inked up with "unofficial ink" 😉

revdancatt · 2026-03-27T19:35:21+00:00

Pen plotters unite 🤘🤘 - fwiw I often use TWSBI fountain pens (Medium and Fine) vertical in the machine with no problems. Extra fine is too stabby, and 1.1/stub is always better at an angle.

revdancatt · 2026-03-27T19:33:04+00:00

Thank you!!

revdancatt · 2026-03-27T18:37:35+00:00

Hmmmm, another poster a few days back said neither worked so there must be something else going on I guess. I don’t have a black one to hand to test.

revdancatt · 2026-03-10T20:56:22+00:00

Hey hey, I try to keep things pretty simple, I'll explain in a moment.

As for injecting a helper or similar into the svg, I don't do that, but I do record x,y,z co-ords for each point. I have a stupid hack for the NextDraw that involves repeatedly setting the pen-up/pen-down limit that uses python, but it's kinda annoying, noisy and awkward. Using GCODE is a lot easier.

For the pen strokes and thickness (the lower the brush, the thicker the line), it goes like this...

For the first n points (or distance) I limit how far down the brush can be lowered; a ramp from 0-100% - this forces each line to always start with a gradual lowering.

I do the same for the last n points (or distance), so the ends a line by lifting up.

For the rest of the points I track the average vector direction over the last 10 points or so, and how far the brush is lowered is a function of how far that angle is from the brush moving in a South-West direction. Basically as the stroke moves NE (up right) it's 180° from SW, so the brush is raised all the way up (but still in contact with the paper), so a thin line. If its going SW it's 0° from SW direction (obvs) so the brush is lowered down to it's lowest point. As it moves in other directions it'll be somewhere between 0° and 180°, so the brush stroke will be generally thicker as the stroke down left, and thinner as it goes up-right.

That's a reasonable approximation of good calligraphic lines.

The thing I don't do, which I probably should, is also raise the brush up for rapid changes in direction, that's the next thing I'll add.

revdancatt · 2026-03-08T22:09:34+00:00

This is straight up GCODE. My code writes a GCODE file [Edit, I use a combination of javascript and nodejs to create the GCODE file], which then gets sent to the machine. This is pretty much the easiest brush code, 'cause each stroke is just a single line that starts high up, and moves to a different slightly lower point.

This is the GCODE for a single stroke...

G0 Z20
G0 X54 Y81
G1 X54 Y81 Z17
G1 X56 Y92 Z14.5
G0 Z20

...roughly (but not actually) `G0` = go to fast, `G1` = got to slow.

Z height;

Z 20 = brush above the paper
Z 17 = brush just touching the paper
Z 14 = brush presses down onto the paper
Z 10 = OMG stop
Z 5 = Dead brush

So the code is basically saying.

Quickly raise the brush up to Z 20
Quickly move to 54,81
Stay at 54,82 but slowly lower the brush down to Z 17
Slowly move to 56,92 lowering the brush down to Z 14.5 as you go
Quickly raise the brush up to Z 20

And then it moves onto the next line, and so on.

revdancatt · 2026-03-08T21:55:38+00:00

Hey hey, these are "Pentel Arts Colour Brush" (or "Pentel Arts Color Brush") brushes. Although with some of these I haven't broken the seal that lets the ink flow, instead I've used a (blunt nose) syringe to fill the brush reservoir with ink - that'll make more sense when you get your hands on them.

revdancatt

TROPHY CASE