Tabletop Simulator is a crowdfunded PC game that lets you play tabletop games, either solo or with up to ten people in multiplayer.
Trailer: https://www.youtube.com/watch?v=JBqernEHjUc
It has a full physics engine that allows you to move, flip and rotate each object or a group of objects. It comes with fifteen games including chess, backgammon, dominoes, poker and some sort of mahjong but you can also make your own games or download thousands of games and assets from the Steam Workshop so you can play traditional card games, complex modern board games, collectible card games or even roleplaying games with 3D terrain and animated figures.
Skor has built a mod that lets you play riichi mahjong. You move the tiles, scoring sticks and wind markers manually but fortunately the wall is built automatically! You need four players (you can find people on the Tabletop Simulator Mahjong group) and at least one person needs to know how to score.
Skor also made a basic implementation of Washizu mahjong using face-up tiles to represent the transparent tiles. Tiles are drawn from the bag in the centre and each player presents their face-up tiles in a second row above the hidden first row containing their opaque tiles.
Screenshots from Sonic's stream yesterday. A replay is temporarily available here.
Mahjong in Tabletop Simulator
Moderator: Shirluban