ODE and Bullet

roxaz · Post by **roxaz** » Thu Mar 29, 2007 3:46 pm

I recently found out that bullet and ode names are often found in one place. even web site design looks almost same. so what are differences and similarities between those two physics engines?

Edit:
btw i noticed that some commercical projects used ODE but GNU license says that relased project which is under that license must include source codes and has to be free. WTF?

xDan · Post by **xDan** » Thu Mar 29, 2007 6:42 pm

ODE is not under the GNU license. It's under one similar to irrlicht's.

I was under the impression Bullet was more of a collision library as opposed to a complete physics library (I even thought they were thinking of incorporating Bullet into ODE instead of the OPCODE collisions).

But actually I think I am wrong on this as the Bullet website states it does rigid body dynamics. So i'd love to know the differences too.

roxaz · Post by **roxaz** » Thu Mar 29, 2007 7:44 pm

copied from official ODE website (http://www.ode.org/ode-license.html) :

This library is free software; you can redistribute it and/or modify it under the terms of EITHER:
The GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The text of the GNU Lesser General Public License is included with this library in the file LICENSE.TXT.
The BSD-style license that is included with this library in the file LICENSE-BSD.TXT.

it is under GNU as we see
and one more:

ODE's BSD license allows you to use the source code free of charge in your commercial products.

so GNU forbids to use project in commercical projects, BSD allows to do that. bit confusing isnt it?

xDan · Post by **xDan** » Thu Mar 29, 2007 9:39 pm

Well I read GNU as GPL. But anyway it makes no difference!

It's under either the BSD or the LGPL.

It's not confusing, just choose the license you like.

And the LGPL just means you have to release modifications to the library, not your program.

And anyway, there's no reason why a commercial project couldn't be open source

sRc · Post by **sRc** » Fri Mar 30, 2007 3:04 am

xDan wrote:(I even thought they were thinking of incorporating Bullet into ODE instead of the OPCODE collisions).

*digs around in ODE mailing list archives*

yep, in fact it is the Bullet developer himself working on it

roxaz · Post by **roxaz** » Fri Mar 30, 2007 7:10 am

xDan wrote:Well I read GNU as GPL. But anyway it makes no difference!

It's under either the BSD or the LGPL.

It's not confusing, just choose the license you like.

And the LGPL just means you have to release modifications to the library, not your program.

And anyway, there's no reason why a commercial project couldn't be open source

aaa now i understand that licenses thingie.

but you see, source relases for commercical project would mean simply quick death

Luben · Post by **Luben** » Fri Mar 30, 2007 1:22 pm

roxaz wrote:but you see, source relases for commercical project would mean simply quick death

Not necessarily, since it's the content of the game that makes it worth playing, not the game engine itself. And you could always invent some strange license that makes it impossible for people to use the source anyway

cassini · Post by **cassini** » Fri Mar 30, 2007 2:09 pm

Luben wrote:
roxaz wrote:but you see, source relases for commercical project would mean simply quick death
Not necessarily, since it's the content of the game that makes it worth playing, not the game engine itself. And you could always invent some strange license that makes it impossible for people to use the source anyway

If the content of the game is what makes it worth playing it, and the license can be colluded so that it cannot be used by anyone, then how the source enhances the game experience?
This is like saying a CocaCola will be better drink if the maker release the recipe. I can certainly see how the recipe will result in detriment of the company decreasing sales in the long run.
I do not see the relevance of the source to a game.

roxaz · Post by **roxaz** » Fri Mar 30, 2007 2:36 pm

take a look at ultima online. game content is incredible but graphics 2D, new client has half - 3d graphics. even best content without good engine is crap

Midnight · Post by **Midnight** » Fri Mar 30, 2007 8:06 pm

xDan wrote: And anyway, there's no reason why a commercial project couldn't be open source

hackers.

xDan · Post by **xDan** » Fri Mar 30, 2007 8:23 pm

Midnight wrote:
xDan wrote: And anyway, there's no reason why a commercial project couldn't be open source
hackers.

I just meant that a commercial project CAN be open source. Of course in most cases it might be a bad idea.