BVE Trainsim (originally Boso View Express[1][2][3]) is a Japanese three-dimensional computer-based train simulator.

[3] BVE Trainsim was designed and developed by Takashi "Mackoy" Kojima[8] starting in 1996[3] with the original program name coming from the Japanese 255 series multiple unit trains found in routes in Japan.

[citation needed] Although the internal working of the BVE Trainsim program itself cannot be modified, additional routes and train cab views can be added[4][5] via a number of text-based configuration files.

[11] BVE Trainsim 4, released in 2005, added support for plugins to simulate train safety systems other than ATS and ATC.

[16] Included in the new release is the Uchibō Line, a newly developed example scenario demonstrating the new features available in BVE 6.

Although the name and logo were originally based on BVE Trainsim, openBVE is free and open-source software developed and written from scratch.

Internally, openBVE makes use of OpenGL for rendering, as well as OpenAL for three-dimensional positional audio.

Despite the lacking developer support, around 2009 openBVE was capable of running most BVE Trainsim routes correctly and also supported additional features, including an exterior view, animated 3D cabs, and animated objects.

[21] To date (May 2017), numerous additions were made by the project: new parameters for animated objects and the plugin API,[22] several unfixed errata from the previous openBVE 1.4.3 errata fixed,[23] Dynamic lighting and backgrounds added,[24] and a basic package format has been added to make the installation of addons easier.