PlayCanvas, a popular 3D HTML5 game engine have added support for Spine the 2D bone based animation software from Esoteric Software.
You can get the plugin from Github, details from the announcement:
This is the first version of PlayCanvas plugin for the Spine Animation tool.
Spine allows you to create bone-driven 2D animations so it does away with the need for huge sprite atlases and tedious animation processes.
Using the PlayCanvas Spine plugin you can drag and drop your Spine Animations into the Editor and get them straight into your game.
Read more on the plugin's Github page