Older blog entries for raph (starting at number 409)

Travel

I had a great time in the Netherlands - both working and having fun. A highlight of the trip was meeting great people like Dave Crossland (minimal web presence) and Jeroen Janssen.

Curves

There are a number of basic algorithms needed for any serious curve application, including stroke offset, intersection, and conversion to lower-level operations for rendering. The standard representation for curves is, of course, piecewise (cubic) Beziers, and in this representation the implementation of all these basic algorithms is reasonably well understood.

However, these problem can't yet be considered solved in the free software world, because there is a lot of software out there that implements them badly (including FontForge, which I'd really like to see improved), and there isn't a really good library out there that you can just call. Rendering, yes, Beziers make that really simple. Stroke offset and intersection, though, are considered pretty difficult in the Bezier formulation. Offset, in particular, has a well-deserved reputation for being numerically tricky when starting from Beziers. See Comparing Offset Curve Approximation Methods for a pretty good survey of the problem.

I've been spending lots of time with other curve representations, including the clothoid (spiral of Cornu). My main motivation has been to make a better UI for editing curves, but I'm starting to get the sense that they may be better for the under-the-hood tasks as well. While in the Netherlands, I worked out a closed-form equation (in Cesaro form) for offset curves of the Cornu spiral, and am inclined to believe that it's both simpler to code and likely to give better results (speed, robustness, accuracy) than previous methods.

I'm blogging this partly to test the waters for a collaboration. I can see that happening in a few different ways. Maybe there's someone out there who really needs a solution to problems like stroke offset, and is willing to consider a new approach rather than a rehash of existing techniques. Alternatively, there might be a bright student or two who really want to stretch their numerical and computational geometry skills, and want to work with a mentor who's put a lot of thought into the problem. Either way, the result is likely to be a journal paper and a codebase published under a nice free software license.

Xara

Dave showed me screenshots and so on from Xara, for which the source code has just been released. I tried building it on Ubuntu Breezy, but ran into just enough make problems to run out of patience. Even so, it looks very interesting. I was getting something of a "too good to be true" vibe from the preannouncements, but now the code is out there, and the people behind it are showing up at free software events like the Libre Graphics Meeting. This project looks like it may well transform the landscape for free 2D graphics tools.

Latin

I'm citing this 1744 book by Leonhard Euler in my thesis chapter on the elastica, and need the following bit of Latin translated into English. Anyone out there who can handily read this, or recommend someone else who can?

ut, inter omnes curvas ojusdem longitudinus, qu\ae\ non solum per puncta A \& B transeant, sed etiam in his punctis a rectis positione datis tangantur, definatur ea in qua sit valor hujus expressionis $\int {ds \over RR}$ minimus.

I have a pretty good idea what it says, but don't trust my own ability to get all the cases and so on correct. And some of the words don't seem entirely standard to me. "ojusdem"?

Netherlands

I'll probably be spending the first couple of weeks of April in Venlo, the Netherlands, visiting a customer site. It might be cool to meet up with some free software hackers and font people in the area.

To follow up on either (or both) of these, my best email address is <firstname>.<lastname>@gmail.com.

LTNB

I have really fallen out of the habit of blogging, but I haven't exactly been a hermit like many of my other blogging lulls. I've been meeting up with quite a few people who have come through town (tor is here now), and generally keeping quite busy. Work, in particular, is hopping right now.

I come not only to bury auto*, but to praise it

I'm not at all surprised by the defenses of auto* in response to my rather harsh criticism.

Dom Lachowicz writes: I've yet to see a build system that attempted to fill auto*'s niche and fill it as well as auto* currently does. I agree completely, and perhaps my praise was simply too faint. The goal of making software building Just Work on a wide variety of Unix-like systems is extremely noble, and until auto*, it wasn't even obvious that it could be done.

I'd like to amplify even more. A lot of good free software is inspired by the existence of good proprietary software, in the sense that Gimp was inspired by Photoshop. If nothing else, the proprietary software represents an existence proof that it is possible to attain those goals.

I think this story applies somewhat to version control systems. We've had consensus for a very long time that CVS needed improvement and probably replacement, but it wasn't really until BitKeeper came along that the lightweight distributed version control systems (such as arch, darcs, and mercurial) started coming out of the woodwork.

Now, in the proprietary platform space, build systems are very slick, but none of them give a rat's ass about portability to other platforms. To the contrary, the nicer an IDE is to work in, the less likely the developer is to escape the golden handcuffs. Lock-in is the highest goal. If we're going to create a much better build system, we have to look to ourselves for the inspiration, because we're not going to find it anywhere else. auto* was the first great existence proof, and I think it is high time for others.

Andy Tai and others call for incremental improvement to auto*, including a gradual phase-out of M4, but, with David Turner, I'm not sure that's really feasible. I believe a program of incremental improvement to auto* will never really be able to reduce the overall system complexity. And I do believe that a much simpler system is possible, especially without the demands of adhering to M4, least-common-denominator make, and least-common-denominator shell.

I admit I did overstate some of my original points for the sake of rhetoric. There are, indeed, good reasons to use other compilers than the GNU toolchain. Ralph Giles takes me to task for not acknowledging the importance of Solaris, but for the applications I'm personally most interested in building (font editors and the like), these vendor Unices are vastly less important than native Win32 support.

Dom writes: Regarding auto*'s tendency to work around deficiencies in ld/cc/nm/etc..., all I can counter with is "we don't control the horizontal and the vertical". In response, I ask: Who does? Bill Gates? Maybe after he figures it out we can try to clone it?

I'm not calling for violent overthrow of the auto* hegemony. I am calling for:

  • A profusion of prototypes of new autoconfiguring build systems, much like the distributed version control systems we've seen come out in the last couple years or so.

  • A careful look at which aspects of make/ld/package managers/etc are holding us back, and clear goals enunciated about how they might be fixed.

  • A more quantitative approach to thinking about building, perhaps empirically measured in challenges, where students are forced to use the tools to build and package a trivial app for Linux, Mac, and Windows platforms, and entries are scored based on time taken, defects in the results, and so on.

I've had a strong enough long-term interest in this field that I am likely to make one such prototype myself. One reason I'm blogging about now is to gauge the waters, to figure out whether there are other people thinking along similar lines, or whether I'm pretty much just pissing into the wind as far as the broader free software community.

auto* delenda est

David Turner (freetype)'s recent post in response to titus reminded me of my own auto* aversion. In sum, I think auto* represents everything that is bad about a free software project.

Don't get me wrong, auto* was (and still is) a tremendous improvement over the bad old days of hand-editing makefiles just to have a chance of having your software build. But it is well past time to have designed, implemented, and deployed a better alternative, and I don't see too many good signs of that.

What's wrong with it? Let me enumerate the ways:

1. It's way too complicated. Good software and free software, not to mention good free software, run on simplicity. auto* does not have this quality.

2. It's implemented in bad languages. One bad language would be enough, but M4, (portable) make, and portable shell? There's a good reason nobody else has even attempted writing an app in that combination of languages.

3. Original goals are no longer very relevant. In the bad old days, there were lots of vendor Unices and other strange build environments. Today, in the *nix world, there is just the GNU toolchain. The amount of actual diversity that needs to be configured around is minimal.

4. It doesn't solve real-world portability problems. For many users, getting programs to build on Windows is at least as important as compiling on an ancient MIPS running Ultrix, yet auto* isn't much help at the former.

5. Bad error reporting. In "configuration science", one of the overriding goals should be production of clear and meaningful error messages.

6. Lack of overall systems thinking. Much of what auto* does is work around limitations in tools such as sh, make, ld, package managers, and the like. If some of these other components are better places to solve configuration and build problems, let's do it there rather than twisting ourselves into pretzels trying to work around them. Apple had the guts to extend ld in several important ways, including two-level namespace support. Why are we still stuck with the clunky late-'80s approach copied from old vendor Unices?

It's been clear for a long time that CVS needed replacing, and now we have a variety of great alternatives, some of exhibit that classic, simple, do-one-thing-and-do-it-well free software philosophy. We should have something similar for the problems that auto* solves.

Japan

I find myself posting from Japan once again. Why is it that I'm more likely to find a free moment here than back at home in Berkeley? Anyway, it's nice and cold, and I even got to see some snow up north in Matsumoto.

The happiest baby on earth

I took a picture of Alan when he was a baby, and for a while it was one of the first-page hits on Google Image search for the keyword "happy". Over time, several people have asked to use the picture.

Most recently, it graces the front page of UC Riverside, where it is used to illustrate a research study on the nature of happiness. That makes it official, when he was a baby he was the happiest on earth.

The funny thing is, the day I took that picture, he was also most unhappy. We were packing for a move, and he was quite cranky that we were paying attention to all these boxes and things instead of him. I took a break for a few minutes, and he was soooo happy, I decided to take a picture. He was still happy to be the focus of attention, and I think the pic shows that.

Nokia 770

rillian brought his Nokia 770 when visiting here, and it seems really cool. The kids liked it, as well - Alan surfed to the neopets site and was able to log in, and Max made a drawing with the sketch (primitive paint) app.

My take is that the form factor is a winner, but I think I'll wait until the second generation to actually get one. The CPU is quite pokey by modern standards, and memory is tight.

It does run Ghostscript right out of the box, though! It seriously looks like it's a lot easier to develop for than your usual handheld.

More trust metric

I got a gratifying response to my trust metric rant in the last post - a couple of emails, some blog comments. It's clear now that I need to do a more detailed writeup of exactly how to implement the eigenvector-based trust metric in the context of a large Wiki.

Pete Zaitcev writes: One half is spam and abuse, and other half is that conventional, highly credible and trusted wisdom is simply wrong. I'm not sure exactly what he means by this, but it may have something to do with the fact that, from the perspective of approximately one half of the population of this country, approximately the other half is under the spell of a mass psychosis in which the usual rules of reality simply don't apply anymore.

It's not clear to me how a large wiki should handle this situation. One intriguing possibility is that the subgraphs of sane people and deluded people both form cliques, so that when a sane or deluded person is logged in and the trust metric is computed from their node, they see a version of the page that is factual and objective, or conforms to the parameters of their delusion, respectively.

The Clever search engine from IBM research has an interesting take on this issue. While PageRank and the Advogato trust metrics compute the principal eigenvector, they also compute some of the others, resulting in "clusters". They report, for example, that the second eigenvector link graph for webpages on abortion neatly separates pro-life from pro-choice. Indeed, this very eigenvector is likely to correlate very strongly with the sane/deluded distinction described above. The sign of this correlation is, of course, left as an exercise for the reader.

Teeth

My teeth are a bit sore. Turned out the cavity I was to have filled today had more decay than expected, so I get to have a crown instead of a filling. Could have been worse, it didn't go into the nerve, so I don't need a root canal.

Time for a website for free font development?

With all the recent activity in free font land, I decided to set my ideas down "on paper", and posted a thread over on typophile. I chose to post it there rather than here because I want the input from people in many different communities, especially type wonks. If you're interested in free fonts, whether as a user or as a developer, head on over and add your 2 {(euro )?cents|pence|yen|whatever}.

Time for a trust metric enabled wikipedia?

I see that Wikipedia is having some well-publicized troubles with vandalism and the like. This will be a somewhat bittersweet response.

The success of wikis has taken a lot of people by surprise, but I think I get it now. The essence of wiki nature is to lower the barrier to making improvements to content. The vast majority of access-controlled systems out there err strongly on the side of making it too hard. The idea of a wiki is to err on the side of making it too easy, and to lessen the pain (somewhat) of undoing the damage when that turns out to be a mistake. In cases where that doesn't work out, I think the solution is to make the decision process of whether to grant write access a bit more precise, so you can still err on the side of trusting too much, but you don't have to err quite as often or as badly.

In that regard, the trust metrics designed and implemented for Advogato are a near-perfect match for the needs of a Wikipedia-like project, but for the most part, nobody is paying much attention to my ideas. Yes, I am bitter about that. I've written them up in a howto and some draft papers, arguably not as polished a presentation as the ideas deserve, but still comprehensible to somebody motivated to understand them. I've implemented them and released the code under GPL. That implementation is too tied to the somewhat quirky mod_virgule design, but adapting and modifying is what free software is all about, no?

So I haven't exactly gift-wrapped the trust metrics and presented them to the world on a silver platter, but they're not sitting at the bottom of a locked file cabinet in the basement of the local planning commission either. With Google now worth a brazillion dollars, due in large part on the success of their eigenvector-based trust metric, and with the problems of spam and abuse showing few signs of just going away on their own, you'd think there'd be more interest in creative, high-tech solutions to the problem.

Let's say for the sake of argument that there's a 50% chance that I'm a raving moron when it comes to this stuff, that my belief that a trust metric would go a long way to solving problems such as Wikipedia's is just plain wrong. Say there's also a 50% chance that there are practical problems I don't forsee, so, while the basic ideas might be valid, they just won't work on a project like Wikipedia. Of course, you can dispute the exact numbers, but that leaves something like a 25% chance that it really would be worthwhile for someone to invest the time and energy into making it happen. How much is Wikipedia worth to people? How much is the idea of decentralized collaboration, especially so that you don't have to rely on "content serfdom" to get the good stuff?

Of course, the Free Software Way(TM) would be for me to pick up a shovel, dig in, and implement a trust metric enabled wiki myself. Well, pardon me for ranting, but in this case I believe the FSW is just plain dysfunctional. A large part of the reason I'm reluctant to invest much more of my own time and energy is the tepid reaction to the work I've put in so far. How is it that a community can generate dozens of IRC clients, me-too distributions, window managers, and PHP bbs engines, and yet leave the development and implementation of the Advogato trust metrics almost completely ignored?

Wow, even I am amazed at the intensity of that rant. I did say this post would be "bittersweet", but so far it's been pretty much all bitter. The sweet part is basically that I have faith that, in time, the Advogato trust metrics will be understood and implemented as widely as deserved based on their ability to resist abuse. Free software development, in particular, operates on a pretty slow clock. My last post contains a striking example - the roughly many year lag between my release of a prototype watercolor simulator and the inclusion of the ideas in an actively developed app.

And already, I see some tentative signs of that. The Wikipedia development boards have some discussion of "trust metrics," although I don't see much evidence they actually understand the power of Advogato's. Additionally, there is some academic work starting to build on my own, including Paolo Massa's evaluations of the various extant trust metrics, and Daniel Stewart's "Social Status in an Open-Source Community", published very recently in the American Sociological Review.

And who knows, maybe even this post, despite the bittersweet tone, will inspire someone to take another look at my trust metric ideas. Hopefully somebody who has the technical ability to implement something a little more sophisticated than the usual PHP hash, and whose idealism about free culture and individual-centered web content has not become quite as jaded as my own. If someone out there were to do a nice job implementing an attack-resistant wiki, that would do wonders for reinforcing my faith in the community.

4 Dec 2005 (updated 4 Dec 2005 at 01:53 UTC) »
Yay, I'm a pro font designer now!

As hinted at last post, TUG has awarded me a grant to complete and release Inconsolata, the monospace design I'm working on. Go take another look - all of ASCII is complete now (but will certainly be refined over time), and there's an OpenType download for Mac and Win readers out there (this should answer fxn's difficulties with trying it).

I find that, of all potentially relaxing creative activities, I enjoy font design the most. I've tried learning some musical instruments, drawing and painting (including a couple classes at Berkeley), and a few other things, but usually I'm just not that good at it. Or, sometimes, it feels like I could do good stuff but it takes a lot of mental effort and concentration. I find that I can draw a glyph or two even when I'm feeling cranky or tired, or that my mind is just not working. I expect to be spending more time on fonts.

The nature of collaboration in free software

I'm often disappointed or frustrated by the lack of collaboration I often feel in the free software community. Of course, a good deal of the fault lies with myself - given any kind of tension or conflict, my natural reaction is to go into hiding. I simply don't have the characteristics you'd find in a natural-born leader.

But one of the best things about free software is that it often lets collaboration happen in roundabout ways. Take my work about five years ago on watercolor simulation. I wrote some code and posted it, and have been thinking on and off since then about how to optimize the algorithms so you can get real-time performance on standard hardware. But I've never actually done that, or packaged up the code I have into a real, usable painting app.

Now, it looks like somebody else is. I got an email today from Bart Coppens asking license clarification to use my code in Krita, which looks like it's developing into a real contender in the space occupied now by Corel (formerly Fractal Design) Painter.

Of course, there is more than a bit of irony here, as some would argue that the development work put into Krita could have been better spent adding similar features to Gimp. But it just doesn't work that way - there's nobody paying the Krita people to do that, and no doubt they're having more fun doing things their own way. There are always decisions to be made differently - choice of programming language, for one thing, so that letting code adapt and even be rewritten is usually the most realistic way to let it live.

I think the same can be said of much of my free software work. Libart isn't being developed, but projects like Cairo and Inkscape are that much richer for having had Libart as a model. That's not hugely gratifying (especially when there are Advogato posts gloating about what a great thing it is to switch from Libart), but all in all it's a contribution I can be happy about.

Fonts

A bunch of things are happening in font-land.

For one, SIL has released version 1.0 of their Open Font License, and promises to be releasing Gentium under its terms shortly. The fact that SIL is getting aware of free software licensing is very encouraging, as it promises to make their efforts considerably more relevant.

Even so, I'm not convinced that the OFL will have that great an impact. Earlier drafts tried to ban selling collections of fonts with OFL fonts included, but apparently that ran afoul of DFSG-style freedom. Now, apparently, it allows selling of collections, but not of the individual font. Was anybody actually selling free fonts individually before? Even if not, the adoption of the OFL may send a signal that the font is to be treated with more respect. As Wes Felter says, it's much like wearing a designer t-shirt. It will be interesting to see how aggressively the "free font" ripoff artists prey on Gentium - if they do back away, it might be an appealing example to follow.

I'm tracking this because I've got a few fonts in the queue that I'd like to release under some kind of free license, but am still unclear exactly what license is best. I've been in touch with Karl Berry having TUG sponsor completion of one or more of the fonts, and the choice of license is still an open issue.

Font fans might be interested in taking a look at my latest font-in-progress, Inconsolata, a monospace design. I'm hopeful that it will turn out to be one of the best available for code listings, etc., in print.

Japan

The trip to Japan was really fun. On the last evening, I had a very nice dinner with Masatake Yamato and Akira Tagoh, both now of Red Hat Japan. We talked of many things, including areas where recent AFPL releases of Ghostscript may break some of the work done by the gs-cjk team to make substitution of Japanese fonts work correctly.

We also talked about free software tools for Japanese learners, and input methods for Emacs in particular. I've been using Quail, mostly because it was easy to find since it's included in Emacs distros, but apparently SKK is better.

One question I have about Quail: is there a way to go in the reverse direction: if I have a kanji in the buffer, can I make it tell me the key sequence required to produce that?

15 Nov 2005 (updated 15 Nov 2005 at 06:00 UTC) »
Hello from Tokyo

I'm posting this from the Manboo comic library and Internet Cafe in Tokyo. It's probably the most uniquely Japanese experience I've had here. After all, cities are cities, and most name brands are global. Given a choice, I'd probably rather go to Fry's than the famed Akihabara district. But this is a concept that would probably only work in Japan, and definitely not in the States.

Basically, the deal is that you pay around $3/hr, which gets you a private cubicle with your own computer, TV, and PS2. Not only that, but you get free run of an impressive library of manga comics, free drinks, clean bathrooms, and a handful of similar perks.

Now, keep in mind, by Tokyo standards, that's an incredible deal. This glass of iced tea cost the company something around $8 at the Tokyo Hilton, a ten minute walk or so away. Refills not included.

The main reason it wouldn't work in the states, I think, is that people just wouldn't respect the space. They'd be stealing all the books and equipment (there's a decent pair of headphones hanging on the wall, no bizarre incompatible connector or other "security" mechanism to keep it there), defacing things for the hell of it, pissing in the cubicles, shooting up (although, truth be told, there rather is a distinctly herbal aroma to the cigarette smoke in here).

Meetings

We had three meetings with three Japanese companies. Two went very well, one was near-disastrous. (I won't name the companies out of discretion)

Doing business with Japanese companies is very difficult for Westerners. There's all of this culture, and what would be a straightforward comparison demo of technical skill can be interpreted as an insult to the engineering capabilities of the host. People talk about "honne" and "tatemae" in terms of great mystery, as if it's impossible for Westerners to grasp, but it's not really that hard.

Take for example, when, at the really fancy Japanese dinner we were treated to at a restaurant in Matsumoto city on Friday, they offered a shabu-shabu of the male reproductive organs of some big fish, nobody was sure exactly what kind. Everybody's looking at me to see what my reaction will be.

So here's honne: "bleaghh, this thing tastes weird, and the texture is even weirder. I'll be lucky if I can get it down."

And, in contrast, tatemae: "Thank you for offering this experience. It is a very interesting flavor!"

Note that both are, in fact, true. I'm going to get a lot of mileage out of this story, much more so than if we had just had nice steaks or what have you. But the Japanese make the distinction explicitly, and pretty much expect it in daily relations. In a way, that's actually more honest than the American way, which is to pretend that it's all honne all the time, but we do it too. (lots of other gaijin have written about this topic - this one is one of the better explanations. And, of course, for insight into how dysfunctional Japanese culture is from the perspective of an American teaching English in the schools, nothing beats Azrael's blog)

Gadgets

I spent some time walking through Akihabara and just letting the gadget-ness wash over me. In some ways, the technological progress is awesome, but in other ways I'm beginning to wonder if the engine may be slowing down.

On the plus side, digital cameras have finally really arrived. I picked up a Panasonic FX-9 (6MP compact) and am absolutely thrilled with it. Good pictures (I've linked one or two from this entry), cool funky features such as the ability to take movies, and even a rotation sensor. (neither iphoto nor yahoo photo knows how to interpret the tag yet, but I'm sure that will happen soon). It's got a 1GB flash card that looks to me just like a 3.5" floppy scaled down to an inch. I remember my first hard drive, it was 20MB and occupied a 5.25" form factor.

But on the other hand, I sense the magic has gone out of it. Sure, the pace will advance. We'll be able to stick more and more songs up our ass. But a lot of the stuff, computers in particular, lacks much in the way of fresh and new. The majority of laptops here still have 1.2GHz Pentium M chips, although of course 2GHz is still available on the high end. Displays are pretty much the same as a few years ago, just a bit brighter, higher contrast, and faster.

I was also looking for a pocket electronic Japanese/English dictionary, but didn't find a model that really appealed to me. They've got relatively pixelly monochrome LCD displays, cost around $300 for a good model with the kanji dictionary and so on, and none of them have features designed to make life easy for a Westerner trying to learn Japanese (an untapped market, perhaps?) It seems to me you'd be far better off with a Nokia 770 and some dictionary software (perhaps even wiktionary-based, which seems to be gaining momentum).

Windows Media Photo

Windows Media Photo is part of the upcoming XPS format from Microsoft. From what I understand, it basically has the advantages of JPEG2000, but without the problem of people other than Microsoft owning patents on it. We may be starting a crash project soon to implement it from scratch. It's too early to tell whether it's going to be kosher to do a true free software release, but we're in contact with the right folks at Microsoft and are pushing on them. Anyone you know have an interest in image codecs, a taste for implementing specs, and a need for some extra walking-around money?

Misc

Now that I have a digital camera, I'm missing more than ever the ability to insert inline images, so I'll want to add that.

I'm also missing the ability for people to write direct followup comments, so much so that I considered writing this as an article. Hopefully now that the trips have wound down, I'll have some time for that. Hmm, where have I heard that before?

iagorubio: sorry about that. My acm account got thoroughly deluged by spam, so I let it lapse. I've updated my contact information, so hopefully it will be easier for people to get in touch with me now.

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