#engines and frameworks

amulet

A free Lua-based audio/visual toolkit suitable for small games and experimentation. It runs on Windows, Mac, Linux, HTML5 and iOS.

Babylon.js

Javascript 3D Library.

Blend4Web

A Javascript framework for creating and displaying interactive 3D computer graphics in web browsers.

Box2D

A 2D Physics Engine for Games.

CopperCube

CopperCube is an all-in-one 3D game engine.Very easy to use.

Coquette

A micro framework for JavaScript games. Handles collision detection, the game update loop, canvas rendering, and keyboard and mouse input.

ct.js

this 2D game engine makes learning programming fun and game development easy by its visual tools, good docs, and flexible, modular library.

E.B.U.R.P

The Eight-Bit Universal Role Playing Engine

engo

Engo is an open-source 2D game engine written in Go.

Ebiten

A dead simple 2D game library in Go.

FlashPunk

free ActionScript 3 library designed for developing 2D Flash games.

gameplay

A free, open-source, cross-platform, 2D + 3D game framework written in C++. It is aimed towards indie game developers who are creating desktop and mobile games.

GameSalad

Game Creation Engine for Mac and Windows.

GB Studio

A free and easy to use retro adventure game creator for your favourite handheld video game system.

ggez

A Rust library to create Good Games Easily.

Gorgon

A 2D rendering API for .NET, written in C#.

Horde3D

small open source 3D rendering engine.

Inform7

A design system for interactive fiction based on natural language.

Ink

Scripting language for writing interactive narrative.

JPCT

jPCT is a 3D engine for desktop Java and Google's Android.