[osg-users] multiple models, single texture

[Terry Welsh]

It looks like SharedStateManager is appropriate for what I'm doing,
but it doesn't seem to be quite as flexible as I'd like.  With the
wide variety of modelers, exporters, and loaders, I can't always be
assured that the DataVariance on StateSets and Textures will be
static.  This is currently a requirement for sharing, though.

The current share modes are

        enum ShareMode
        {
            SHARE_NONE      = 0x00,
            SHARE_TEXTURES  = 0x01,
            SHARE_STATESETS = 0x02,
            SHARE_ALL       = SHARE_TEXTURES |
                              SHARE_STATESETS
        };


Would it be too weird to append these modes like so?

        enum ShareMode
        {
            SHARE_NONE      = 0x00,
            SHARE_TEXTURES  = 0x01,
            SHARE_STATESETS = 0x02,
            SHARE_ALL       = SHARE_TEXTURES |
                              SHARE_STATESETS,
            SHARE_TEXTURES_DYNAMIC = 0x04,
            SHARE_TEXTURES_UNSPECIFIED = 0x08,
            SHARE_STATESETS_DYNAMIC = 0x10,
            SHARE_STATESETS_UNSPECIFIED = 0x20
        };

I've already tried it with textures and it helps out a lot when you
can't easily control what's in your model files; I can submit it if
this looks good.

The only problem I see is that SHARE_ALL no longer makes much sense,
but changing it would break backward compatibility.  And it would look
weird to have SHARE_ALL_NO_REALLY_SHARE_ALL.
- Terry

>
> Message: 11
> Date: Fri, 27 Jun 2008 09:32:15 +0100
> From: "Robert Osfield" <robert.osfield at gmail.com>
> Subject: Re: [osg-users] multiple models, single texture
> To: "OpenSceneGraph Users" <osg-users at lists.openscenegraph.org>
> Message-ID:
>        <7ffb8e9b0806270132h67587bf1jb4c88209811a89f6 at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Hi Terry,
>
> On Fri, Jun 27, 2008 at 5:01 AM, Terry Welsh <mogumbo at gmail.com> wrote:
>> Is it possible to load multiple model files that use the same texture
>> but only have the texture get loaded once?  It seems like a good way
>> to save memory and reduce state changes.
>
> The loaders don't cache images and textures, but it is possible to
> combine duplicate state once the data is loaded.  The
> osgUtil::Optimize::RemoveDuplicateState can be used on a whole scene
> graph, and the osgDB::SharedStateManager can be used when you are
> incrementally loading subgraphs.
>
> Robert.
>