Everything you never wanted to know about Jon Watte

I've been wanting to put the ICSP 6-pin header onto a soldered Arduino circuit.

This is so that I can make "emergency" fixes even if I've removed the Atmega MCU from the USB-powered board I normally use to prototype and program. Also, even if I socket it on the destination board, moving it too many times back and forth risks significant damage to the pins!

This took me a while to track down. I figured I'd document it for posterity, and anyone else trying to do asynchronous networking in C++ using boost::asio. I'm using Ubuntu Server 10.04 LTS with gcc/g++, which uses boost version 1.40. The reason is that the "bytes transferred" argument to the callback is the number of bytes until the separator is found, but more bytes than that are decoded from the socket into the input stream.

I recently answered question on the gamedev.net multiplayer and networking forum, that I feel warrants further distribution. The question dealt with trying to use MySQL eventing and MySQL data as the "server" for a large-scale multi-player web-based game.

I was unhappy with the low resolution of the visualization data that you get out of the XNA framework MediaPlayer. If you want to synchronize gameplay to music, the data you get is not sufficient.

Here's a number. Anyone care to guess what it is?

2003529930406846464979072351560255750447825475569751419265016973710894059556311
4530895061308809333481010382343429072631818229493821188126688695063647615470291
6504187191635158796634721944293092798208430910485599057015931895963952486337236
7203002916969592156108764948889254090805911457037675208500206671563702366126359

In my previous blog entry, I talked about cross-shard transactional integrity for key/value stores, and how SQL databases have solved this problem. I also poked fun at some of the best known key/value stores for not quite solving all of my problems for me, for free. Go read it, it's fun times!

I've been looking at NoSQL data stores for online transaction processing lately. Yes, related to work :-)

The basic model of a key/value store, where the value is a JSON object or similar, only gets you so far. The bonus with it is that it is very, very easy to horizontally partition ("shard" or "federate"). The draw-back is that you really can't do any online queries on anything other than primary key values. If you're trying to do a query on, say, "any foobar created between 2011-01-05 and 211-01-06" then you're screwed -- you have to traverse the entire data store to find that.

I made a Node.js module. It's a packaging and slight update of the JavaScript implementation of the Mersenne Twister random number generator (which is a really high quality generator, as well as pretty fast).

I'm hoping you can soon get it with npm:

$ npm install mersenne
$

Usage is simple:

r = require('mersenne');

XNA Game Studio makes it possible to write games for the Xbox without being a developer with good publisher contacts and lots of money to pay for marketing and Xbox development kits. This is great!

However, because the XNA Indie Games system is not fully controlled by Microsoft, certain features of Xbox Live! are not available, because they would be too easily abused. These features include online Leaderboards, and unlockable Achievements.

The XNA community has developed alternatives to those functions. Many XNA games contain "Awardments" that can be unlocked, and many more XNA games use the XNA Network Highscores component to implement distributed, peer-to-peer highscore sharing. The name for this is generally "Online Highscores" rather than "Leaderboards," because the latter name is reserved for use by Microsoft-certified titles that use the real Xbox Live! functionality.

This article introduces version 2 of the XNA Online highscores component, which is free for you to use in your own game under the terms of the MIT license.

I've been doing some Android programming, trying to get a feel for what an Android app would look like when structured as a main screen, some set-up screens, and a main gameplay screen (which then wants to go back to the main screen). I've fought a bit with the built-in Android layout views. They seem to be missing some capabilities that would be really useful.