[osg-users] Why isn't OpenSceneGraph used in games?

[Terry Welsh]

Hi Michael,
After building 1.5 games using OSG, I'm surprised there aren't more.
OSG is probably built to be general-purpose first and high-performance
second. So this might scare away someone building an extremely
high-fidelity game. But for anything less OSG is fine. Also, being
free and having an extremely active community counts for a lot in my
book.

When I meet other devs they're usually surprised (sometimes shocked
and amazed) that I'm not using Unity or some other popular game
engine. So the main reason OSG isn't popular for games may be that
there is a huge swath of younger developers that don't know C++ or are
daunted at the idea of building a game with it.

>From my first game, nothing about OSG registered as a big performance
problem unless you count osgParticle. I wrote my own OpenGL particle
systems, partly for better performance but also because I wanted some
features not available in osgParticle. The other big performance
issues came from shaders (purely a problem with OpenGL and graphics
hardware) and computing stuff that was off-screen (purely a game logic
problem).

Concerning your particular problem of rendering large areas of rural
and urban terrain, many of us on this list have done that at high
performance with OSG. OSG contains good tools for spatial organization
of your data and LOD. If you use all of it and avoid novice mistakes
(like putting transparency in your low-LOD models), you can get
seriously high performance. Of course, a game engine tuned for that
specific type of game should do more for you automatically and lead
you toward good decisions.
--
Terry Welsh
http://www.reallyslick.com


>
> Message: 9
> Date: Thu, 21 Apr 2016 16:07:12 +0200
> From: "Michael DeForge" <mdeforge at simcreator.com>
> To: osg-users at lists.openscenegraph.org
> Subject: Re: [osg-users] Why isn't OpenSceneGraph used in games?
> Message-ID: <1461247632.m2f.66906 at forum.openscenegraph.org>
> Content-Type: text/plain; charset=UTF-8
>
> Can anyone explain to me why OpenSceneGraph isn't used in the games industry? There seems to be a large stigma surrounding OSG's performance, but is there really a problem here or not? OSG's own website claims "high performance". Is it really?
>
> I've heard reports that people have had to keep their scene graphs shallow otherwise the lookups become too expensive. Makes sense, but is that enough to disqualify it for use in games?
>
> My problem is that we have to render very large expanses of terrain in urban and rural environments. Think GTA, but for simulation research purposes, not entertainment.
>
> I know OSG is used a lot in the simulation industry but I don't understand why when there's better tech out there.
>
> I'm not trying to incite a flame war, I just want a straight honest answer. We're considering many different frameworks and engines right now and OSG seems like an iceberg that I'm trying to steer us away from.
>