Ben North's blog.

Covering various topics, usually of a vaguely nerdy nature.

01 April 2017

'Splat the zombies' 3D game

I recently got another long-running collaboration to the point of having something to show — a first-person shooter in the browser. This was an idea which Sally, my youngest, had. She drew a bunch of house fronts, and also some 'zombies', and then a map of the world where the action takes place. The result […]

29 January 2017

Exponential Mazezam level family

As a correction and follow-up to a previous post, I constructed a family of Mazezam levels whose solutions are exponential in the size of the level. Many thanks to Aaron Williams for pointing out my error to me. Full write-up and demo on GitHub.

09 November 2016

Joining and mapping government data sets

A while ago, the principal at the primary school my children attend remarked at how time-consuming it was for her to manually collate two different sources of information on schools, and cross-reference against a map of schools' locations. Her task, as I understand it, was to find nearby schools who might want to pool their […]

07 October 2016

Bletchley Park 'Rectangling' and LDPC codes

For now, this is my final post arising from the General Report on Tunny. I looked at the connection between: 'Rectangling', part of the cryptanalysis performed by the Bletchley Park codebreakers on the Lorenz cipher, and Belief Propagation decoding of LDPC error-correcting codes. See the write-up and code repo for details.

12 September 2016

Literate programming with git

As a follow-up to the previous post on git dendrify, I've been experimenting with using git to present the development of a piece of software in a more human-readable way. The hierarchical organisation described in the git dendrify README allows the history to be rendered into a structured and interactive document explaining the code's development. […]

15 June 2016

git-dendrify — a tool for transforming git histories

I've been working with git for a while now, and have been experimenting with it as a way to present the history of a piece of code in a way which makes it easier for a human reader to understand. One way I think git can help with this is by adding structure to the […]

14 May 2016

(Some of) Colossus on an FPGA

An implementation, on an FPGA, of the parts of the Colossus code-breaking computer needed to replicate the Chi-wheel-setting worked example of the previous post.

12 April 2016

Replicating Colossus's Chi-wheel setting

A worked example of one part of the cryptanalysis performed by the Colossus computer at Bletchley Park during World War II.

23 February 2016

Bike Game in Scratch

Just over a year ago, my son (then 6) wanted to create a computer game where you drive a bike round a world. I helped him with this, and we've worked intermittently but fairly often on it since then. There were quite a few details to get right, but he worked through them a bit […]

13 September 2015

Flying over a trampoline

Origin of idea A couple of months ago, Sally (5) was bouncing around on the trampoline at my in-laws' house, and said something very close to: 'Dad, you should take lots of pictures of me jumping in the air, and put them together into a video, then it will look like I'm flying'. I thought […]