A New Open-Source Game Engine Being Released

[IanS]

A perfectly fine opensource license is Apache license. It is not copyleft, it does not protect against license withdraw, but at least it gives some good structure and patent grants.

This is a good point, Apache 2.0 may actually be a better fit for this project due to the patent protection, it is otherwise mostly identical in nature to the MIT licenses.

Something else worth noting while deciding which license to settle on is that there are at least 2 different licenses that are commonly referred to as the MIT license, the Expat license and the X11 license. They are both acceptable and mostly the same, but they are also old and don't deal with patent issues which may or may not be a concern for you and your team. If you do want to be sure that patent issues are covered then the Apache 2.0 license would be a better alternative and the one I would probably settle on.

[amagnoni]

wow!!

im waiting impatience for testing this engine!

[amagnoni]

This is a good point, Apache 2.0 may actually be a better fit for this project due to the patent protection, it is otherwise mostly identical in nature to the MIT licenses.

Something else worth noting while deciding which license to settle on is that there are at least 2 different licenses that are commonly referred to as the MIT license, the Expat license and the X11 license. They are both acceptable and mostly the same, but they are also old and don't deal with patent issues which may or may not be a concern for you and your team. If you do want to be sure that patent issues are covered then the Apache 2.0 license would be a better alternative and the one I would probably settle on.

i prefer Apache. but if they want MIT, why not?

GPL is great but not for releasing paid games.

[mrugiero]

i prefer Apache. but if they want MIT, why not?

GPL is great but not for releasing paid games.

It's not that bad for paid games, the problem is for games that target consoles or iOS/W8.

[IanS]

Another license worth considering is the Boost software license which is almost identical to the MIT Expat license except that some of the wording is much more precise and less ambiguous.

For instance Expat says,

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

While Boost says,

The copyright notices in the Software and this entire statement, including the above license grant, this restriction and the following disclaimer, must be included in all copies of the Software, in whole or in part, and all derivative works of the Software, unless such copies or derivative works are solely in the form of machine-executable object code generated by a source language processor.

With Expat it isn't clear what a substantial portion is, while Boost makes it explicit with "in whole or in part". Boost also makes it clear that it is unnecessary to include the license when distributing only object code, while Expat doesn't. The Expat version also neglects to explicitly include the disclaimer as something that must be included with the license.

Another example is in the warranty disclaimer; in Expat,

IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE...

In Boost,

IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE...

In this case the Expat license only clears authors or copyright holders from liability (which is at least in part redundant as all authors would be included among copyright holders), while Boost's disclaimer covers copyright holders and anyone distributing the software.

Another small difference in the first paragraph of each license is that Boost mentions "any person or organization" while MIT only mentions "any persons" which could lead some to interpret the Expat license to mean that it doesn't apply to organizations.

The rights listed are also more clear and concise in Boost;

...to use, reproduce, display, distribute, execute, and transmit the Software, and to prepare derivative works of the Software, and to permit third-parties to whom the Software is furnished to do so...

Compared to Expat;

...to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so...

[V10lator]

Except, that on iOS devices, you cannot install any apps from any external sources, only via the appstore. (Unless you jailbreak, but expecting your customers to jailbreak their iPhablets isn't really a viable business model for most.)

Not 100% true. You can install signed apps without the appstore. The problem is the signing that apple does while adding your app to the store but some (pirates) seem to have found a way: Just google for tongbu, go on the side with your (not jailbroken) iOS device and you'll see that you're able to install an app that apple would never allow in the store.

But all of that is off-topic (and most likely illegal) and not interesting for a commercial product, so all I really want to say: This looks interesting, can't wait to see what we get from it.

[dee.]

Not 100% true. You can install signed apps without the appstore. The problem is the signing that apple does while adding your app to the store but some (pirates) seem to have found a way: Just google for tongbu, go on the side with your (not jailbroken) iOS device and you'll see that you're able to install an app that apple would never allow in the store.

I don't have an iOS device, jailbroken or otherwise

(And never will have.)

[Apopas]

Juan Linietsky, thank you very much for your answers. I'm looking forward to put my hands on your very interesting project!

[Apopas]

I don't have an iOS device, jailbroken or otherwise

(And never will have.)

Exactly! There is no need.

[MistaED]

This looks incredible guys and thank you for putting the effort into open sourcing it, I can't wait to check it out!

Please don't make it (L)GPL, no one will use it then outside of the GNU community. BSD/MIT/ZLIB and now Apache 2.0 are probably the only ones to consider.

The biggest strength from the screenshots is that it looks mighty impressive as a flash/AIR replacement for the web if it can export to HTML5/WebGL, I'm guessing through Emscripten? The editor sounds like it could be bundled with a released game itself without licensing restrictions which is great for releasing a runtime moddable game.

How does the 3D physics work, is it based on Bullet Physics under the hood? The animation system and editor by what I've read and from the screenshots looks incredibly developed, are there exporters for programs outside of Blender, do you support FBX or Collada import?

I'm really interested in the rendering, from what I read the engine focus is around the ES 2.0 API and the editor control looks quite high-level on top of that. Can you get into the guts of the renderer at the shader level and render stages via a script/data-driven approach for if you want to make something like a deferred renderer or is it too high-level and you'd need to implement that kind of stuff at the C++ level with separate shaders for the targeted backends?

Is the engine largely single-threaded? Are scripts interpreted at runtime or can they be JIT/AOT compiled at runtime? AOT would be great for iOS where you can't execute JIT things, and on HTML5/javascript which would be horrible for performance I'd imagine if it were interpreted at runtime...

Thanks for the info! Sorry for the many questions...