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Genetic_algorithms. Blog » Blog Archive » Game of Life text and image generator g. I saw this image the other day on Hacker News and Reddit: It’s a Game of Life pattern that prints out “Golly”.

blog » Blog Archive » Game of Life text and image generator g

Neat, but I wanted my own. After about 5 minutes of playing around with the Golly logo pattern in Golly (a program for experimenting with the Game of Life), I gave up and wrote a program to do it. The program takes the top and bottom portions of a template pattern (based on the Golly pattern) and positions them, then fills in the gliders between them for the correct number of columns.

Then it duplicates the entire pattern for each row. This was great, but I had essentially created a dot matrix printer that could draw anything, so it would be a waste to not draw images with it. The code is available on GitHub. Download Golly to open up the generated “.rle” files. The Memory Pool System: Thirty person-years of memory management. Collected Algorithms of the ACM.

Functional Programming in C# 3. As a developer who was raised on procedural and object oriented programming languages like C, C++ and Java it took me a while to figure out what people were raving about when it comes to the benefits of functional programming techniques.

Functional Programming in C# 3.

I always thought closures and higher order functions were words used by snobby kids from MIT and grad students to show how overeducated they were as opposed to programming tools I'd ever find useful. This thinking was additionally fueled by articles like Joel Spolsky's Can Your Programming Language Do This? Which not only came off as snobby but also cemented the impression that higher order functions like map() and reduce() are for people solving "big" problems like the folks at Google who are trying to categorize the entire World Wide Web not people like me who write desktop feed readers in their free time. All of this changed when I started learning Python. There are more examples from the RSS Bandit code base but I'm sure you get the idea. Anti-Aliased Line Drawing. First, let's start with an example to show why we want to use anti-aliased lines.

Anti-Aliased Line Drawing

The lines on the left are drawn with something like Bresenham's line algorithm. The lines on the right are drawn with an extended form of Bresenham's which anti-aliases. They are shown both at normal size and 4x zoom. Which do you think looks better? For MP4, you need to implement the one on the right. Just take me to the algorithm!

There are several models one can use to draw anti-aliased lines, with differing quality results. But when I want to display that on a screen, and my units above are individual pixels, I simply cannot draw that. Rasterization. Graph Visualization Test. List of algorithms. Highly Efficient 4 Way Merging. Acknowledgements: This article is based on the work of Peter Sanders and Roman Dementiev.

Highly Efficient 4 Way Merging

You can find the full source code presented here in their STXXL library (STL library for large data structures), Peter Sanders' paper and the accompanying source code. Warning: If you are of sensitive nature either regarding computer science theory highly practical program optimization then I recommend you to stop reading this article at once. You might faint or something. Maybe, however, you can get a “bling” moment out of this article. Do you remember Mergesort from your introductory course in programming or computer science?

/* Merge two already sorted arrays where both are terminated * by 0x0fff ffff which may not appear *inside* arrays. */ void merge2(int a[], int b[], int result[]) { int i = 0, j = 0, k = 0; while (true) { if (a[i] <= b[j]) { result[k] = a[i]; i += 1; k += 1; } else { result[k] = b[j]; j += 1; k += 1; } if (result[k] == 0x0fffffff) return; } } Can we do even better? Template. A More Random Computer Input Controller. Dictionary of Algorithms and Data Structures.