If you look at the lein cljs-build sample project, you’ll see that it states:

; The :builds option should be set to a sequence of maps.  Each
; map will be treated as a separate, independent, ClojureScript
; compiler configuration.

If you look at the example right below that description, you’ll see that it is actually set as a map of configuration profiles with the configuration name as the key. So what gives?

Read More

I participated on a fascinating panel yesterday at the (still ongoing and live-streamed) nucl.ai 2015 conference. One question asked by Richard Kogelnig, the moderator, was why have new input devices like Kinect and Leap Motion have failed to really penetrate the consumer market, and what sort of a device would really have a chance at making a difference.

I don’t think it’s a technical problem. I think it’s a message problem.

Read More

Starlings

A recurrent question about UnitySteer is how to implement behavior like that of a flock of starlings (seems that Mr. Reynolds was right on the money when he chose flocking for his paper).

Usually the person who writes mentions that their implementation is “getting there”, but they’re not quite happy with the result yet. The main issue with the question is that if the results are right or not are all about perception - it’s not a problem where there is a single, provably optimal solution.

With that in mind, I’ll detail some of the aspects of the starlings from the video above, and mention how you can mimic them in UnitySteer.

Read More

Introduction

Tropology is an experiment in visualizing conceptual networks from TVTropes. The initial idea was that, starting from a chosen concept, we could visualize the list of tropes and articles it referenced, along with the relationships between them.

Experimenting with the data, which even after some judicious pruning includes over 220 thousand nodes and 11 million relationships, led me to quickly conclude that the model was too widely connected. We couldn’t just visualize the raw data and needed to apply some sort of direction in order to make the visualizations sensible.

Let’s see how to go about that.

Read More

Or, apples vs. papaya salad.

Short version: I’ve moved Tropology to PostgreSQL for performance reasons, and because after some evaluation, Neo4j wasn’t as good a fit as it seemed at first blush.

You may want to start by catching up with the other Tropology articles.

All done?

Read More

The story so far

Yesterday we were discussing our (admittedly) somewhat ghetto, not-quite-batched Neo4j implementation.

The long and short of it is that I was initially attacking the import process as one would on a JDBC client for a relational database. Query for these values here, create those if some don’t exist, insert relationships here, etc.

That seems to be woefully inefficient in Neo4j.

Read More

Introduction

This is the first part of a series of articles on a small experiment I’m building. The intent is to crawl TVTropes, to find possible relationships between tropes and the material they appear in, as well as shared concepts.

I want to be able to not only visualize a concept and the tropes that it links to, but also how they relate to each other. A bonus would be being able to query how far away a concept is from another - for instance, how many steps we need to take before we can go from Cowboy Bebop to Macross Missile Massacre.

Read More

This one bit me a bit hard and, seeing as I could find only one reference for it in the context of Clojure and Leiningen, I thought a small write-up would help.

After including some ClojureScript code on my project, lein started barfing when I attempted to build an uberjar with any optimization settings other than none.

Exception in thread “main” java.lang.NoSuchMethodError: com.google.common.io.ByteStreams.limit(Ljava/io/InputStream;J)Ljava/io/InputStream;, compiling:(/private/var/folders/64/ckdtdxm14059n9wh8rhf1mvw0000gn/T/form-init527739448955044836.clj:1:123)

There was only one obscure reference I found, from an IRC chat now a couple of years old. My first thought was that something in the ClojureScript code was throwing off the compiler, but it seemed odd that this would trigger a call to a specific non-existent method.

Other searches - outside of the lein context - made me realize it was actually a dependency conflict, and only triggered on uberjar because since there wasn’t any ClojureScript code deployed before the compiler hadn’t had to be invoked.

Calling

lein deps :tree

showed there were multiple versions of com.google.guava being referenced, with the one used by ClojureScript being 18.0 but a much older 11.0.1 being referenced by urly. Seems like lein either doesn’t realize there’s a conflict or defaults to the older library, which was causing the error when ClojureScript attempted to build.