irrlicht is described as 'The Irrlicht Engine is an open source high performance realtime 3D engine written in C++. It is completely cross-platform, using D3D, OpenGL and its own software renderers, and has all of the state-of-the-art features which can be found in commercial 3d engines' and is an app in the Development category. There are more than 10 alternatives to irrlicht for a variety of platforms, including Windows, Linux, Mac, Android and iPhone. The best alternative is Torque 3D, which is both free and Open Source. Other great apps like irrlicht are OGRE (Free, Open Source), Pygame (Free, Open Source), JMonkeyEngine (Free, Open Source) and OpenSceneGraph (Free, Open Source).
OGRE (Object-Oriented Graphics Rendering Engine) is a scene-oriented, flexible 3D engine written in C++ designed to make it easier and more intuitive for developers to produce applications utilizing hardware-accelerated 3D graphics.
Pygame is a set of Python modules designed for writing video games. Pygame adds functionality on top of the excellent SDL library. This allows you to create fully featured games and multimedia programs in the python language.
JMonkeyEngine3 it’s a free, open source game engine, made especially for Java game developers who want to create 3D games using modern technology. The software is programmed entirely in Java, intended for wide accessibility and quick deployment.
The OpenSceneGraph is an open source high performance 3D graphics toolkit, used by application developers in fields such as visual simulation, games, virtual reality, scientific visualization and modelling.
Ursina makes it easier to develop games, visualizations and other kinds software. The concise API combined with the power of the Python programming language, makes life easier for the developer so they can focus on what they are making.