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-# kotlin-raycaster
-A simple pseudo 3D raycasting engine in Kotlin-JS
+# Kotlin Raycaster
+
+A simple pseudo 3D [raycasting](https://en.wikipedia.org/wiki/Ray_casting) engine written from scratch in Kotlin, targeting the browser with [Kotlin/JS](https://kotlinlang.org/docs/reference/js-overview.html) and rendered using only vertical lines drawn on an HTML5 canvas.
+
+Interactive demo [here](https://jamesbarnett.io/raycaster)
+
+![](https://jamesbarnett.io/files/raycaster/raycast2.png)
+
+## Process
+Raycasting is a simple rendering technique allowing [2D map data](https://github.com/jamesbarnett91/kotlin-raycaster/blob/main/src/main/kotlin/Map.kt) to be shown in 3D perspective.
+It has several limitations, most notably that all walls must be vertical and of the same height, and the camera perspective can't move vertically up/down (although it's possible to implement these by extending the core raycasting concepts).
+
+Raycasting was used in early 90's 3D games, most famously [Wolfenstein 3D](https://en.wikipedia.org/wiki/Wolfenstein_3D).
+
+For a in-depth explanation of raycasting see the links below
+- https://lodev.org/cgtutor/raycasting.html
+- https://permadi.com/1996/05/ray-casting-tutorial-table-of-contents/
+- https://github.com/vinibiavatti1/RayCastingTutorial/wiki
+- https://dev.opera.com/articles/3d-games-with-canvas-and-raycasting-part-1/