Codename One Tutorial Shows How to Build a First-Person 3D Dungeon Game

The third installment of the Game Builder tutorial series extends the data-driven design approach from earlier 2D tutorials into a first-person 3D dungeon experience called Crypt Walk. Built using Codename One, an open-source Java and Kotlin framework for cross-platform app development, the project uses the same authoring workflow but renders elements as GPU-powered 3D models under a perspective camera with lighting. A key distinction from 2D development is the use of mesh assets in glTF or .glb format instead of sprites or image sheets, with the framework's GltfLoader handling runtime rendering. The tutorial introduces play styles such as dungeon, open, and flight, which automatically configure the camera, movement model, and collision behavior to match the chosen genre. Developers can build maze walls using a Terrain Wall brush tool, which joins adjacent cells into seamless corridors and enforces wall collision in dungeon mode without additional configuration.