---
title: "Calculating Dynamic Light and Shadows Tutorial"
subtitle: "Part 1 covers Bresenham’s line algorithm for use in a roguelike."
date: 2015-12-17T00:00:00.000Z
category: tutorial
url: https://phaser.io/news/2015/12/calculating-dynamic-light-shadows-tutorial
site: Phaser - https://phaser.io
copyright: © 2026 Phaser Studio Inc. All rights reserved.
---

# Calculating Dynamic Light and Shadows Tutorial

*Part 1 covers Bresenham’s line algorithm for use in a roguelike.*

![image](calculating-dynamic-light-shadows-tutorial.png)

From Emanuele Feronato: "I love roguelike games. From the simple ASCII games to more complex turn based games like Sproggiwood. I also made some blog posts about roguelike games. One of the features a good roguelike game should have is dynamic light and shadows, as well as a “fog of war” effect.

Although it may seem complex, I’ll show you this feature in a way you will find it a lot easier than it seems. I will use a logic similar to the one used in the creation of a survival horror game, but this time we are dealing with tiles.

In this first step, we’ll see the algorithm which will be the core of dynamic lights in tile based environments: Bresenham’s line algorithm."

[Read More](http://www.emanueleferonato.com/2015/12/10/calculating-dynamic-light-and-shadows-in-tile-based-roguelike-games-part-1-bresenhams-line-algorithm/)

---

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