Well, after a lot of reading about entity-component/component-based approaches to creating games (that famous article called "evolve your hierarchy" started everything), and after failing to find some good open-source alternatives to those comercial component-based engines, I realized that I won't lose a single penny if I try to create something.
Thus, I want to present this game engine that I am working on. Its component-based and data-driven, its also meant to be cross-platform (almost-free of platform-specific code). Objects are created by attaching components and defining parameters shared between components of the same object, so kinetics component writes to x and y, that the renderer component reads to know where to render the object surface. Every object is defined using yaml files and you can create new components using the component API if you like, without recompiling the engine. Components are loosely coupled and meant to know nothing about each other. They can also listen to value changed notification so they know when a interesting parameter happens to change its value.
The project is being developed using C++ and SDL, but I plan on adding a bind to lua, so you can access parameters in your code like they are a normal var. It already have a set of basic components like spatial and kinetics, a collider, a rigidbody and a renderer. I plan on adding a OpenGL renderer if/when I get comfortable with OpenGL.
I've made a video (almost 20 minutes...
) explaining how to use it:http://youtu.be/1c7ptRL59W8
Its website is http://gear2d.sourceforge.net
Alongside with it, there's a game called Pongroids, which is a pong-like game with asteroids in the field.
qubodup recorded a video of it:
http://www.youtube.com/watch?v=xyd-6_C8 ... re=related
You can read more under Games section of the above site. if you watch that video you'll notice its buggy.
Well thats a hook for the "contributor wanted" part of this post. I am very dumb when it comes to physics and math, and so I cannot do collision detection and response properly. Those correspond to collider component and rigidbody component respectively. Both of them are poor in their tasks, and I would appreciate help from someone either that understand physics relatively well or understand how to use those physics engines. One limitation is that collision detection must be separated from collision response, and many game engines do it together (thats why I've been relutant to use them)
Apart from that, if someone is interested to add that lua binding i mentioned (so you can create new components using Lua), be welcome. Or that OpenGL renderer component. Or just a "hello world" component.
Any feedback and help is appreciated. We have a irc channel on freenode, #gear2d, be my guest and join us, even if its to complain that this post is too long.
Thanks!