Reducing Tiled Maps to Optimized Collision Rectangles with Greedy Merging

A Tiled collision layer is just a dense grid of cells. By applying greedy rectangle merging, that grid can be reduced to a small set of non-overlapping rectangles that describe the exact same area, but are far cheaper to use at runtime. Full JavaScript example available with source code.

2026-01-30

dwm 6.8 released: download

This fixes a regression in getatomprop(): https://git.suckless.org/dwm/commit/a9aa0d8ffbb548b0b1f9f755557aef2482c0f820.html

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It is encouraged to upgrade to 6.8 or HEAD if you use dwm 6.7.

The cults of TDD and GenAI

I’ve gotten a lot of flack throughout my career over my disdain towards test-driven development (TDD). I have met a lot of people who swear by it! And, I have also met a lot of people who insisted that I adopt it, too, often with the implied threat of appealing to my boss if appealing to me didn’t work.

The basic premise of TDD, for those unaware, is that one first writes a unit test that verifies the expected behavior for some code they want to write, observes the new test fail, and then one writes the implementation, iterating on it until the test passes. The advantage...

Greedy Rectangle Merging: Turning Binary Grids into Simple Geometry – JavaScript example

Greedy rectangle merging is a practical way to simplify dense binary grids into a small set of axis-aligned rectangles. By making local decisions and never backtracking, the same area can be represented with far fewer geometric primitives, revealing how different expansion orders lead to different results. JavaScript source code available.

HTML5 prototype of a planet gravity platform using Phaser 4 and Arcade physics, written in TypeScript

A gravity-rotating movement system built with Phaser 4 and TypeScript, where a character walks around floating terrain by dynamically reassigning gravity instead of falling off edges. Movement and jumping are defined in surface space rather than world space, allowing seamless transitions around corners while keeping Arcade Physics fully in control.

Understanding QuadTrees: organizing space to reduce unnecessary work

QuadTrees organize space instead of objects, allowing spatial queries to skip large, irrelevant areas with a single check. This makes proximity searches and collision detection far more efficient in games and interactive applications. In this article, we explore how QuadTrees work and visualize them with a practical DOM-based example.

Processing Astronomical Images with Python and OpenCV

Let’s Look Deep Into Space

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Is QSpy still cool? Let's play QuakeWorld!

Building a 1997 Quake PC: Benchmarking GLquake

Building a 1997 Quake PC: Benchmarking Vquake