[osg-users] Loading problem, OpenVR integration

[Lorenzo Valente]

Hi Robert! Thank you for your kind reply.


robertosfield wrote:
> Is the scene static or is your application adding new scene graph
> objects through the lifetime of the application?


The scene is completely static and motionless :)


robertosfield wrote:
> It's only new objects that you need to compile to make sure that the
> graphics objects are created and ready to download to the GPU


Ok, perfect. I'm pretty sure that the compilation process is already performed on the entire scene by the system I'm working on.
Do you think that my problem could be caused by a missing compilation of objects? If you say that it might be the case, I will investigate more on this.


robertosfield wrote:
> The other issue might be that the graphic objects have are all
> compiled already but not download to the GPU.  Also if the GPU memory
> is full the driver has to start moving graphics objects in/out of GPU
> memory on the fly which can cause big frame drops.


Do you think this might be the case? Is there a way in OSG to tell if an object is already in the GPU memory? And to push them there?
I remind you that once I scan the all scene with my vision the problem disappears and I can look around without any frame drop.
So I guess that the GPU memory is enough to handle the whole scene, I just need to force some sort of "pre-loading" of ALL objects.


robertosfield wrote:
> What specifically you need to do to resolve the problem depends
> entirely where the actual bottleneck is, we can't answer this without
> knowing more about what is happening your scene graph, how much
> headroom you have on the GPU to handle the extra memory usage,
> bandwidth and compute work.


As I said, my conclusion is that I don't have any actual system bottleneck, I just have to get rid of this lazy loading process :)
I just need to tell the GPU "hey, here's my scene, I know you can handle it all, just pre-process it in one shot and don't wait for me to look around!"
But I could be completely wrong and I'd love to know what you guys think about it. I want to 1) learn more about OSG and VR 2) solve this annoying problem.

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