This is a powerful raycasting 3D engine running 2D games with Pen in 3D. [ HOW IT WORKS ] The engine sends rays from the player position. If the rays are touching an 2D object on the map (modify it!) then the information about angle and depth are send to the renderer. After the scanning process, the Builder draws a frame. This happens very often and fast. The method / algorithm is called raycasting.
Thank you, scratch! More performance: https://turbowarp.org/500553126?turbo&hqpen