Category: Stuff with computers

“What do I do with that lime?” or “The genesis and state of my cocktail book index”

Published on by Balise3 Comments
Two martini glasses with a clear liquid and an olive in each, over a seamless grey/white background

A while ago, I bought an excellent book, called Drinking French, by David Lebovitz. It’s not strictly a cocktail book because there’s lots of stuff in it, but I’ll admit that I’ve only tested the cocktail recipes so far.

I have also, since then, bought another excellent book, called Cocktail Codex, also a staple next to my liquor cabinet.

These two books have a few common issues:

  • their (paper) index does not make it easy to search for a cocktail that have two distinct ingredients (apart from looking at the index and finding the intersection),
  • their index is not complete and, in particular, does not contain “trivial” ingredients such as lemon juice or simple syrup,
  • their index does not necessarily account for substitutions I may feel confident doing,
  • they don’t have a common index and I’d need to have a look at both to make decisions.

So I typically find myself in a situation where I have limes, and no idea what I can make with them, except it’d be nice to have something with gin. Also, I’m not that picky and probably if you give me a recipe with lemons, I’ll put my limes in it instead and call it good enough. So, the problem that I was trying to solve was: “given a set of cocktail ingredients, give me ideas for what I can make with them, allowing for some fuzziness in the exact research”.

With that problem in the back of my mind, roughly at the same time, I read Index, A History of the, by Dennis Duncan (a book about the art of indexing), and I became somewhat fascinated by Wikibase (the Mediawiki-base software backing Wikidata, which handles structured data). Things kind of clicked to “WHAT IF I re-indexed the books in a Wikibase instance, I added some structure to the ingredients for the fuzziness, and I made SPARQL queries to get exactly what I want?”

So I did that – I installed Wikibase, and I started re-indexing. I added some structure to the data by adding “subclasses of” and “instances of” and “can be substituted by” and “such as”, and it was glorious. Then I gave some thought about the exact query I was interested in, and I ended up with something along the lines of “given a list of ingredients, for each of them, get a list of substitutes, and give me a recipe that contains at least of one substitute of each ingredient of the list”, where “substitute” is defined as either the ingredient itself, something that is explicitly defined as a substitute, or something that is (transitively) either a refinement or a larger category of the ingredient. The reasoning there is that, if I input “London dry gin”, I want to get the recipes that have “gin” (without qualifier), but also the ones that have a specific brand of London dry gin.

I bundled a small Mediawiki extension called CocktailSearch to be able to query my database and, for a while, I was happy. Here’s an early version of that interface (I had added the page number in the meantime too!)

Screenshot of a Mediawiki interface showing the CocktailSearch extension, displaying results for a search for lime juice and Cointreau.

And then, doubts crept in. My Wikibase install was run via the Docker images. It worked pretty well, but I was a bit unhappy with running 9 Docker images, including one that kept restarting (I probably could have fixed that one, but eh), on a machine (my home Windows desktop computer) that wasn’t really suited for it. I’m not much of a system administrator and I have 0 confidence in my Docker skills in general: the whole setup was making me a bit nervous. Migrating my cocktail index to a more persistent setup became my new project.

I considered multiple options, including “just moving the Docker images to another machine”. I finally settled on trying to run Wikibase, without the Docker images, on a Raspberry Pi that we have laying around. I actually went pretty far in the installation, and I think it could have worked out. But again, I got really nervous about the durability of the setup – Raspberry Pis are not known for being particularly good at data persistence. On top of that, getting from something that “mostly works” to something that I could plug in and access three minutes later with everything running looked like a goal that I might be able to eventually reach, but software rot was a real concern. I felt stuck.

I talked about that with my husband, who pointed out that my usage of SPARQL was actually fairly limited (it is, in fact, limited to a single large query), that my data was actually very very small (maybe a thousand records), and that I could maybe… not use SPARQL, and then not need the whole Wikibase machinery either. I was not convinced at first, because killing your darlings is hard. I had invested quite a bit of fondness in that architecture, and I did like the idea of running mostly standard software. But it didn’t take that much thinking before I actually got excited about the idea of simplifying the whole project drastically.

So, I exported my data to a JSON file, and I started hacking some import script. I then looked at my imported data and at my SPARQL query, hacked some loops in PHP, and essentially called it a day: my SPARQL query and my PHP queries were returning the same results for my few test queries.

Then, came the question of completing the database – indexing takes time, and my base was (and is still) not complete (and, who knows – maybe I’ll index some more books later!). While I’m able to programmatically read the dumped Wikibase JSON, I’m definitely not able to write it by hand without a lot of tears; but continuing to run Wikibase just as an input interface felt a tad excessive. Hence, I transformed my JSON structures into a flat file format that I could easily write by hand and easily parse. I added a significant amount of validation to avoid typo-duplicates and missing item references, and I re-exported my JSON data into that new format. I double-checked that I wasn’t losing any information (I’m indexing a bit more than I need, technically, because I’m also taking notes on the glass type, for instance), and then I started trying to complete the file with new items.

I honestly thought I wouldn’t last three recipes without slapping some kind of interface/completion on that file format, but it’s going significantly better than I expected. I did modify the file format a bit to make it easier to edit manually, at the cost of reading through the file twice when parsing it (I can live with that; and if I couldn’t, I could optimize there, but why bother :P). It feels like it’s enough: I have a validation script that runs fast enough with good enough error messages that I can input things and correct them more quickly and more pleasantly than I did with the Wikibase interface.

Speaking of interface, I also slapped a small web interface on the script, so that I can search with completion and have a readable output. The search completion was also far less involved than I expected: turns out the <datalist> tag does exactly what I want, assuming I pass a list of ingredients (which I can get as “transitive subclasses and instances of the ingredient item”) to the generating HTML. And there, new interface, new results – with additional data entry done in the meantime too 🙂

Screenshot of a HTML table displaying search results for cocktails with limejuice and Cointreau

So anyway, that’s the genesis of the current version of my cocktail book index, which is now called LimeCockail in reference to my original “now what do I do with these limes”.

It does feel a bit of a convoluted path for something that, at the end of the day, is, like, 500 lines of PHP, give or take, but going through that path was very interesting for a variety of reasons. It did give me some hands-on experience with Wikibase (granted, without the issues that come with “running a public instance” 🙂 ), and the Wikibase RDF structure helped me define my structured data in a way that makes sense to me. I also stretched my (almost nonexistent) sysadmin muscles to try to make all of this work together, and I (re-)learnt a few things about the LAMP stack and ElasticSearch. I also got a bit more experience with SPARQL, and I touched jQuery for the first time in a long time to be able to hack the search components backed by Wikibase data. All in all, this project taught me a lot of things!

Now I just need to finish indexing the Codex… 🙂

It’s Advent of Code again!

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Yup, for the 7th year in a row: it’s Advent of Code time!

Advent of Code is an advent calendar of programming puzzles. Every day of December until Christmas, you get a new puzzle and a piece of the yearly story in which you need to help the elves save Christmas because Santa is in trouble! In the previous years, we’ve repaired the snow machine, the clock that guides the sleigh, the printer that prints the nice and naughty list, time itself, we brought Santa back from the edge of the Solar System, and we tried to take some vacation last year but it was complicated. It seems this year we need to fetch the keys to the sleigh that got dropped in the ocean by a clumsy elf…

The format of the puzzle is a problem and an input (there’s a number of different inputs, assigned randomly (as far as I can tell) to all the users); the solution (typically a number or a short character string) is what matters to prove that you solved the problem. This means that you can solve it with any language you see fit… or even no language at all. There’s a guarantee that all problems can be solved within 15 seconds on 10-year-old hardware, but it may require some more significant work to get there.

I love Advent of Code. The puzzles are interesting and the difficulty ramp up is usually great, the story is whimsy, and it’s good fun. There’s a competitive aspect to it: there’s a leaderboard for the first 100 people to solve the puzzle, and there’s a “private leaderboard” feature on the website that allows to compete with friends or colleagues. I found it a great way to stretch my coding muscles and practice another language.

This year I decided to solve it in PHP: I’m still learning the language (which I’m now using in my daily professional life), and if previous years are to be believed, I’ll probably learn more than a few tricks – looking forward to that! I’m publishing my (ugly) solutions on GitHub as I go: Balise42/AoC2021.

The first day is easy… who’s in? 🙂

Time tracking with timewarrior

Published on by Balise1 Comment

I’ve been working from home for a bit more than a month – or, as we say around here, “doing home office”, which is apparently a typically German turn of phrase 😉 Since I’m working part-time (60%), and days and hours tend to melt into each other, actually tracking the time that I spend working has proven pretty useful for me to dose the “right” amount of work: make sure I’m working the hours I’m supposed to work, make sure I’m not working significantly more than the hours I’m supposed to work. For those who know me a little, they’ll have an inkling that my issue is more the latter one than the former, with me being much more worried about the former than the latter 😉

I had done that sort of tracking a long while ago with some software called arbtt. It was fairly neat when it came to automating that tracking (and that’s why I’m mentioning it here explicitly): it uses the mouse focus to determine on which window you are working, identifies said windows by their titles, and allows to define rules to classify which belongs to what. I ran that thing for a while when I was working as a freelancer, and that worked pretty well – if you’re not allergic to Haskell. (My window manager is in Haskell too, so I can survive :p )

This time around, I didn’t feel the need to fight with arbtt rule system to fit everything into categories that would be too fine-grained for my liking; after a bit of poking, I found timewarrior. There’s a package on my Ubuntu, so I just installed it, and I started tracking.

In timewarrior, you track by associating tags to intervals of time. For instance, when I start working on documentation, I open a terminal and type

$ timew start work doc

and it starts an interval tagged with work and doc. I have a very coarse set of tags: my current tags are doc (writing documentation), qa (helping our QA department with testing our software), meeting (daily and weekly status meetings, mostly) and social (when I’m socializing with colleagues, not necessarily being productive per se, although such discussions are very often fruitful). To that, I add a generic work tag to these all categories except social, so that I can easily tally my whole work hours. I’m not actively developing these days, but when that comes back, I’ll handle tags for that as well. I also track lunch when I go for my lunch break 😉

Whenever I start a new interval, it automatically closes the previous one – so if I switch from timew start work doc to timew start lunch, the interval lunch starts, and the interval work/doc is closed. If I want to stop the current interval without starting a new one (typically at the end of the day), I just go 

$ timew stop

and no interval is running anymore.

To display what’s been logged so far, timew summary is the way to go. I actually experimented with tracking my Sunday yesterday, and if I want to know how long I spent cooking, I can look at my cuisine tag that way:

[isa@wayfarer ~]$ timew summary :yesterday cuisine

Wk  Date       Day Tags       Start      End    Time   Total
W17 2020-04-26 Sun cuisine 11:28:00 11:59:00 0:31:00
                   cuisine 18:04:59 18:28:09 0:23:10
                   cuisine 18:44:23 19:05:10 0:20:47 1:14:57
                                                            
                                                     1:14:57

It gives me all the instances and a sum of the time I spent overall during the day. This is particularly useful for my work usage: I tag everything I do for work with work, and that allows me to keep track of the amount of work I’ve put in the day.

If I forget to start or stop an activity, it’s trivial to do a posteriori if I’m in an “open” interval, slightly more tricky but still feasible if I need to re-insert things in the middle of other things. Generally speaking, I haven’t found something that I wanted to do that I didn’t find how to yet. The interface can be somewhat clunky, but it’s surprisingly input-flexible (the easy example is that I can do “timew start work doc” or “timew work doc start” or even “timew doc start work” – and it’ll start tracking an activity with tags doc and work in both cases).

The documentation is also very good, allowing both discoverability of features and reference. There’s also ways of getting pretty charts, to export data as JSON, and to develop extensions.

Obviously, if you’re looking for something that synchronizes between several computers, or that you can use on your phone, or or or…. this may not be the software for you. (Although running it somewhere on the internet and tracking via SSH would probably be a viable option). Me, I just want to open a term, type timew start mystuff, close my term, and be done with it – and I don’t care about tracking different things on different computers, because the context of what I’m tracking is different anyway. If your needs align with mine, I can only recommend you have a look at timewarrior 🙂

Advent of Code 2019

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2019 was the fifth year of Advent of Code – and I consequently spent December waking up at 6AM and spending a lot of brain cycles solving puzzles to bring back Santa from the other side of the solar system, where he was stranded.

Let me quote myself to describe the whole thing to the people who are not familiar with it.  Advent of Code is an advent calendar with puzzles that can mostly be solved by programming: the input is a problem description and a user-specific input (as far as I know, there’s a set of a “few” pre-validated/pre-tested inputs), and you have to compute a number or a short string, and provide that as a result. If you have the correct result, you unlock a star and the second part of the puzzle, which allows to unlock a second star. Over the course of the 25 first days of December, you consequently get to collect 50 stars.

When I wrote my Advent of Code 2018 blog post last year, it was December 26th, and I had solved everything – this year it took me until yesterday (so, December 31th) before I got the 50th star. I don’t know if the problems were harder or if I got worse at solving them (maybe a mix of both?), but I still made it before the end of 2019, so I’ll count that as a win 🙂

This year, I worked in Kotlin, a JVM-based language designed by JetBrains, and that I enjoy quite a lot – it is fully compatible with Java, and allows for a much terser syntax, and requires to do things explicitly when it comes to mutability of variables and collections. I like it. My solution repository is on GitHub – beware, here be dragons… and spoilers!

And, like last year, let me give a few impressions of the different puzzles for this year. I WILL spoil the problems and at least hint at their solutions – if you want to start solving the problems with no preconception at all, you may want to stop reading here 🙂

Continue reading “Advent of Code 2019” →

New monitor, new setup!

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I just replaced my 24″ monitor with a new shiny 27″ – 3 more inches in the diagonal, but 4 times more pixels – which required a bit of tinkering – so here’s a bit of a write-up, so that a/ I can share what worked for me and b/ I have something to refer to myself whenever I do that again (I’ll probably have to tinker is some similar ways for the laptop…)

General setup

I have a fairly… personal setup – it DOES work for me, but it’s definitely in the “less common” category, which makes searching for information somewhat more challenging.

  • First things first, obviously: I run Linux, specifically right now Ubuntu 19.04 Disco Dingo – that’s probably the most standard element of my setup.
  • I run it with xmonad/xmobar/dmenu as my user interface.
  • My main screen is now a 27″, 3840×2160 (very pixels, wow)
  • I have a second screen, left of my main one, as a secondary screen, which I mostly use for “browsing documentation when I’m doing something on the main screen” or “chat window when I’m playing in full screen on the main screen”. It’s a 19″, 1280×1024. So, yes, that means multiple-DPI setup – I will admit that the thought had not crossed my mind when I bought the new one. Eh.

So, essentially, this looks like this:

Display configuration

I have a fair amount of things running in the browser, so the first thing I experimented with was changing the scale of the pages of what I was browsing. That went okay on the large screen, but then the scale was completely off for my secondary screen – and switching scale levels depending on the screen would have been a major pain. There is some automated and experimental stuff there; since my setup is already atypical, I decided to not dig much more into why it didn’t work. (I tried. Vaguely.)

I ran into a reasonable solution almost by chance (I didn’t know exactly what I was looking for) here: Configuring mixed DPI monitors with xrandr. I’m now scaling the secondary monitor by a factor of 1.5, which makes it still “good enough for my use” when it comes to the look of the screen (it’s wobbly on my terminal. I can live with that.) and which is “compatible enough with my large screen” when it comes to displaying stuff that’s configured for my large screen.

I’ve been running a “screen setup” script for a long while (which I basically run every time I boot my computer – both on the laptop and on the desktop), so it was a matter of editing the xrandr line to the following:

xrandr --output DVI-D-0 --scale 1.5x1.5 --output DP-2 --pos 1920x0 \
    --mode 3840x2160 --primary

So from there, I know that whatever I do on the large screen is going to be “good enough” on the secondary screen.

Chrome

Chrome has been a bit of a pain. My first attempt was playing with the default scaling of the rendered web pages and fonts, but the tabs and the UI were still (as expected) super small. I finally found the right flag, specifically --force-device-scale-factor=1.5. As far as I can tell, there’s no way to make that configuration persistent at Chrome level (or, at least, I didn’t find it). And since I’m not starting my browser from an icon or a shortcut or anything like that, I couldn’t set it up there either. I ended up creating a google-chrome launch script in my personal bin directory (which was already setup in front of my PATH, thankfully, otherwise I would have required additional yaks) to pass the flag.

Moreover, the flag worked to scale the UI, but it also re-scaled the web page rendering, so I had to roll back my earlier config attempts. But now everything is fine and I can use Chrome without squinting too much, yay.

The “Save” dialog is still tiny, but I really don’t want to try to fix that now, so it’ll wait.

xmonad / xmobar / dmenu / trayer

My top bar with xmobar and the trayer were feeling a bit cramped, and so did my dmenu (the text-based launcher I use to start everything else). Some adjustments were required there:

  • I changed the configuration of the xmobar position in .xmobarrc to read position = Static { xpos = 1920, ypos = 0, width = 3456, height = 30 } ; the xpos parameter is set to 1920 because I don’t want that bar to be present on my secondary screen (and it’s setup to have a width of 1920); the width is 90% of 3840 so that I have 10% of the width for my trayer.
  • I wouldn’t have needed to touch my xmonad config if not for the fact that it’s launching dmenu, and that dmenu’s config is in the command line; I just modified the font of dmenu so that I have ((modMask, xK_p), spawn "dmenu_run -fn xft:terminus:style=medium:pixelsize=22") to start dmenu on Mod-P.
  • Finally, I only changed the height of the trayer (since the width is expressed as a percentage of the total width) so that it now reads trayer --edge top --align right --SetDockType true --SetPartialStrut true --expand true --width 10 --transparent true --tint 0x191970 --height 30 --monitor 1 &. This part is in my “setup screen” script, so the modification here was minor.

gnome-terminal

I use gnome-terminal as my standard terminal: it’s the only thing I ever managed to configure exactly as I wanted it (set of colors, unicode handling, non-blinking cursor, and that sort of things.)

The font was on the small side on the highres display, so I switched to Terminus Regular size 22. I’m not convinced yet by that choice, because it feels bolder than I think it should be, so I may have to play with alternate choices at some point or another. For now, it’s good enough. And I don’t care about the UI scaling in general because I don’t use “anything else than writing on the terminal” often enough for it to be a problem.

Slack

I just zoomed to 150% in the default preferences in Accessibility. The menus and whatnot are still tiny, but I actually don’t care (because I don’t use them much). Good enough for now.

Darktable

Darktable the software I use to do most of my photo post-processing. The picture area is much nicer on the new screen (ahem. It may also have something to do with “the picture area is much nicer on a clean screen.), but the interface was also very tiny. Two things there:

  • in .config/darktable/darktablerc, set screen_dpi_overwrite=150 – I didn’t feel the need to experiment more with other values, this works for me
  • in the UI settings (available from the interface), set the “width of the side panels in pixels” to 400.

It is necessary to restart Darktable after this modification.

GIMP

Since I also started to learn how to use GIMP, it did cross my mind to set it up during my initial setup. Two things:

  • I defined the icon size to “Large” in Preferences > Interface > Icon Theme
  • I also defined the font name to “sans 16” in my theme file, /usr/share/gimp/2.0/themes/gtkrc (defined in Preferences > Interface > Theme).

And this can be reloaded without restarting Gimp 🙂

IntelliJ / CLion

I’m using IntelliJ at work, and the rest of the JetBrains IDEs at home. These days, I’m using CLion to develop on Marzipan (my fractal generator). IntelliJ scales its interface depending on the UI font size; so in Settings > Appearance & Behavior > Appearance, I modified the custom font for a size of 20.

This doesn’t modify the editor font size, though, which needs to be defined in Settings > Editor > Font.

Also, I know have a stronger incentive to continue working on my fractal generator: now that I have a higher res screen, I’m tempted to generate high res images, so I need to optimize that 😉 And also probably to decouple the size of the image from the size of my UI 😛

World of Warcraft

I’ll admit, WoW is one of the first things I tested after plugging in everything and checking that basic function was there. I’m running WoW on WINE – and this was actually the least painful experience: it started without problem, the UI scaled properly immediately, and everything was just as I left it. The only difference is that the cursor is smaller (and that I probably need to modify my mouse sensitivity). But all in all, flawless. And it still runs 100fps, which is cool. (I did feel the need to triple check that I was indeed running in that large resolution. It seems I am.)

Slay the Spire

Other game I play a lot, Slay the Spire – there, I had to adjust resolution manually, but once that was done, nothing to see here, move along.

Conclusion

This may seem like quite a lot of work, and some snark along the lines of “if you ran Windows/MacOS/GNOME/KDE you wouldn’t have to configure things in such a gazillion places” may be warranted – but to me the “having things exactly as I want them” is definitely worth a bit of extra work – as well as knowing that once the configuration is stable, it doesn’t break at every update 😉

I’ll probably find a couple more things to fix in the near future, and I’ll update this post with my findings.

Marzipan update – now with context menu!

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It may seem trivial, but I unlocked an achievement on Marzipan: I added a menu. I’ve been wanting to have a few “quality of life” improvements for a while now, but so far I had been hiding under the duvet of “I really don’t want to touch the UI/Qt code more than I strictly have to”.

My experience with graphical toolkits in general has never been great. It’s really out of my comfort zone; I tend to find that the tutorials on the Internet don’t have anything between an equivalent of “Hello, World!” and an equivalent of “here’s some advanced quantum mechanics” (I do suck at physics in general as well); I kind of have the impression that my use cases are dead simple and should just Be Available As Is and that For Sure I Don’t Need To Read All That Documentation. (Yeah, yeah, I may be somewhat guilty here.) And I get upset and impatient, and generally speaking it’s not a good experience – neither for myself nor for anyone else in the room. (My apologies to my husband!)

But when you’re the only coder and the only user of a project, at some point biting the bullet gets inevitable. Consequently, in the last pull request, I did a fair amount of refactoring. When I started my coding session, everything was contained in a QWindow, in which I was painting an image directly on the QBackingStore. I then read a bunch of stuff about menus, which made me update my QWindow to a QMainWindow – for which the QBackingStore seems less trivially accessible, so I modified that. But then, the refresh was only working when resizing the window, which kind of sucked (and I’m still not entirely sure why). So I put a QWidget inside my QMainWindow as a main widget, and that allowed me to have both the refresh and the menu – yay! I needed to tinker a bit more to get back the keyboard control (move them from the QWidget to the QMainWindow), and now it’s all nice and shiny.

The undo/redo function itself is basically storing the fractal parameters in a couple of stacks and re-computing on undo/redo – nothing fancy (and my memory management is utter shit – read “nonexistent”, I really need to fix that – and I don’t handle storing the orbits properly yet, but one thing at a time.)

As a result: I do have at least half-functional Undo/Redo, and more importantly, I have a reasonable base for future UI/QoL development: I hope that the major hurdle of figuring out how things might fit together is behind me, and I’m a bit less scared of it.

I can’t say I’m happy with that session, because I still have the impression that I tried to put stuff together while having no idea what I’m doing, and while having the impression that I’m not actually learning anything in the process, but this may actually be better than I think. We’ll see 🙂

Some more Marzipan bitmap fun

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I did track down my zoom/scaling issue that I was mentioning in the previous post, and I improved the distance map for my bitmap orbit coloring. I’m still not 100% happy with it – I need to think a bit more about what I want to do there exactly, but it’s still enough that I spent a couple of hours yesterday playing with Marzipan as a “fractal generating software” and having fun with it, and not only as a “software project I’m working on”. Granted, the “UI” is still mostly “let me change the color palette and recompile”, but I was having too much fun making pretty images to dig into making the UI usable 🙂

So – here are a few pictures from my last “creative” session 🙂

Purple explosion

For “Purple explosion,” the seed bitmap is a bunch of rectangles of the same size put randomly on the canvas.

Rainbow equation

“Rainbow equation” is dedicated to Matthias, who was the one mentioning I should put the set equation in the image. And it’s rainbow because why the hell not 🙂

Lace flowers

“Lace flowers” uses one of the brushes from GIMP (Manju’s Flower – Large) as its base. I quite like this one, except for the fact that my processing of the flower should be smoother so that the end result is also smoother. That’s how I learn 😉

Tux funnel

For “Tux funnel”, I used as a base the Tux Mono drawing by gg3po, Iwan Gabovitch, GPL licensed, via Wikimedia Commons.

One of the things that amuses me is the ephemeral quality of what I do here. Choosing to save a picture (and that’s still somewhat of an ordeal) is the only way to keep a trace of what I’m doing. I cannot get back to an image and try to “keep it, but improve it”: since I don’t have my settings and I don’t remember where I zoom, any new attempt will be a new image. I even didn’t keep my seed bitmaps so far – so reproducing an image would really be hopeless. And I quite like it that way.

Marzipan – bitmap orbits (and some bugs)

Published on by Balise3 Comments

I worked a bit on Marzipan this week-end, and started playing with bitmap orbits. The idea is the same as for point orbits and line orbits: we look at the iterations of the escaping points, and we look at the distance on the plane between the complex numbers represented by these iterations and a given set on the same plane.

Since my creativity was apparently all used up by trying to make the algorithm work instead of trying to find a nice bitmap to play with, I simply have the name of my project somewhere on an image, as black&white. I pre-compute a distance map to that bitmap (in a very approximate and most probably buggy way right now – something’s not quite right there, but good enough for a first approximation) and I use that distance map to display the points I’m interested in when rendering the fractal.

The very annoying thing is that I do have a bug on the zooming algorithm – things tend to flip and/or to go to weird places. I haven’t been able to track it down yet: it must be said that I’m typically hopeless at handling 2D grids and scaling factors without breaking a neuron or two, and that on top of that, as mentioned previously, I’m probably making my own life miserable by using a non-standard window manager. I’ll probably need to go to KDE or something to debug this thing properly (sigh :/)

Still, in the meantime, I’m not unhappy with the results 🙂

Marzipan progress

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Today I added a couple of features to Marzipan, my fractal generator, so I’m going to show a few images of what I worked on 🙂

First, I refactored the orbit trap coloring to be able to expand it with other types of orbit traps; then I added the implementation for line orbit traps. Turns out, adding random line and point orbit traps is pretty fun, and can yield pretty results!

A mix of line and point trap orbits

The other thing that I did was to add “multi-color palettes”: instead of giving a “beginning color” and an “end-color”, I can now pass a set of colors that will get used over the value interval. Which means, I can get much more colorful (and hence incredibly more eye-hurting) images!

Yay, rainbows!

And, well, I can also combine these two approaches to get NEON RAINBOWS!

Yay, NEON RAINBOWS!

Finally, I also played a bit with the ratios of the image that I generate – the goal is to not distort the general shape of the bulbs when zooming in the image. This is still pretty unsatisfactory, I need to make that work better (and to understand exactly how the size of the Qt window interacts with my window manager, because I’m probably making my life more complicated than it strictly needs to be there).

I had a lot of fun today implementing all of that, and then losing myself into finding fun colorings and fun trap orbits and all that kind of things. Now, the issue is that if I have more colors, I have more leeway to generate REALLY UGLY IMAGES, and I may need to develop a bit of taste if I want to continue doing pretty stuff 😉

Now what crossed my mind today:

  • I believe I have a bug, either in the multi-color palette or in the orbit trap coloring – I’ve seen suspicious things when zooming on certain parts (colors changing whereas they should not have), so I’ll need to track it and fix it. I also made performance worse when playing with multiple orbits for laziness reasons, I’ll need to fix that too.
  • I have some more things that I want to experiment with on orbit traps – I think there’s some prettiness I haven’t explored yet and I want to do that.
  • I should really start thinking about getting a better UI. I want a have better UI, I don’t want to code the better UI 😛
  • I should at least add a proper way to save an image instead of relying on getting them from the place where I dump them before displaying them – that would be helpful.
  • I should also find a way to import/export “settings” so that a given image can be reproduced – right now it’s very ephemeral. Which is not necessarily a bad thing 😉
  • I can probably improve the performance of the “increasing the number of iterations” operation, and I should do that.
  • The “image ratio” thing is still very fuzzy and I need to think a bit more about what I want and how to do it.