DC-SDK is based on the open source project Cesium for development
Phaser is a free and fast 2D game framework for making HTML5 games
A web-based IDE for HTML5 game development. Powered by Phaser
Draw and edit Lines, Bezier Curves, Splines at runtime
3D .NET engine for Windows, Linux, Mac
A Flash Molehill (Stage3D) GPU accelerated 2D game engine