For what IT worths

Back in May 2006, I needed to performance-tune a web application built on Plone. The symptom was an unacceptable 60 seconds delay upon creating a new user account on top of the already existing 10000 accounts. The source of the delay was very soon traced back by Zope’s built-in call profiler to GroupUserFolder, where the solution was instantly obvious.

The original method was checking for existing users by using linear list lookup, which is known to be algorithmically slower than dictionary key lookup. Knowing that, the performance patch was a no-brainer, and, as expected, it eliminated the reported delay. I’ve sent this patch to ingeniweb (the author of GroupUserFolder) in an email on 22 May 2006, but haven’t heard back from them since. Yet, the patch has been accepted, even got refined a bit and was applied on the code trunk on 13 Jun 2006. From the one side, I’m happy to see it at least being fixed, while on the other side, I could have been more happy receiving a feedback on my report.

Nevertheless, I was still wondering how exactly the two lookup methods compare, so I’ve put together a python script to check how much we can actually gain on using haystack_dict.has_key(needle) instead of needle in haystack_list. I’ve compared them with small to larger sample sizes in small to larger sets (and lists) of samples.

I’ve used TOPCAT, an excellent, yet easy to use visualization tool for tabular data, to graphically represent the results.

As you can see, even at the small sets of small samples region, has_key performs much faster, and with the growing set and sample sizes, it keeps performing equally well, while list lookup goes wild in the same time.

Can’t say I was surprised or learned anything by doing this, but thought I’d mention as it might turn out to be useful for someone out there, so let me know if you’ve found this useful.

This year the Helvetica typeface is celebrating its 50th anniversary, so everyone is talking about fonts. Not that I’m about to propose a replacement for Helvetica, or anything such, still I’ve created my very first font, and therefore I’ve wrote this post about it.

Although my blog logo is still just scraped, it’s time to write about the making of the font used there. I felt spending a couple of hours creating the font makes things learned worth sharing.

I named this font ArcNBrick mostly because of the basic concept behind its glyph shapes, where everything is built up of - surprise - arcs and bricks.

The tool I’ve chosen to build the font was FontForge, a cross-platform, open source application designed for the very purpose of creating fonts of different types.

Let’s take a quick tour of how I’ve started building a font with FontForge. First of all, the concept behind my font allowed me to work without any pre-drawn, scanned helper images, even though FontForge supports those. Let’s discuss the basics of drawing glyphs, then.

• All paths are built up of curve, tangent, and corner points. Curve points are marked with a circle, tangent points with a triangle, and corner points with a rectangle.
• Control points (marked with x) help you to shape the curves as desired.
• Outer boundary paths should be drawn clockwise, while inner boundaries counter-clockwise

After learning these very few basic rules from the tutorial, I was very soon up to speed in drawing the glyphs for all the letters. In order to accelerate the process and also preserving design consistency, I used cheap transformation tricks to create glyphs from one another. For example the letter b is a perfect candidate to create letters d, p, and q.

So, drawing letter d consisted of the following operations: select all on letter b, copy, paste to letter d, then element: transformations: transform: flip horizontally, and finally element: correct direction. Drawing letter p wasn’t much harder: select all on letter b, copy, paste to letter p, then at element: transformations: transform: first flip vertically then move y by -200, and finally element: correct direction. That was it. Very soon, all letters took shape, so I’ve built the TrueType version to give it a go.

As you can see, the result is nothing useful for everyday use, yet, you might find it appealing for short, emphasized labels used in logos, for example. Should this be the case, feel free to download and use my ArcNBrick.ttf. Make sure to leave a comment here on where and how this font was particularly useful for you, I’d be happy to receive feedback!

I need to confess that I haven’t tackled any of the issues that would make a font professional, such as hinting, accents, proper encodings, to name a few, but by this time you’ve already guessed that I am by no means a typographer. Yet it was fun building a unique font from scratch and seeing it working in a word processor. Some day I might even try building some wingdings fonts too, who knows…