vrscene and particles

[simonbjork]

I'm trying to render a scene via VRay Cloud but I'm having some problems. The scene has a single flat polygon (textured with an image sequence) and replicated (via a Surface particle generator) about 70.000 times. The camera is animated but the particles are static.

When I try to export this to a vrscene file via the VRay Cloud sumbitter, I get huge files and it takes forever. I didn't let it complete, but after 20 frames it the size on disc was already almost 3gb. In my scene has about 200 frames.

Is there anything I can do to speed up the export and reduce file-size?

- In a simple test I had my scene range to be 10-20. But when exporting a .vrscene it seems like it exports frames 0-120 for some reason? If I had my range at 500-600, it seemed like 1-100 was exported, but I guess that it's not using actual frame numbers in that case?

- If I uncheck the "This Replicator is Animated" I still get a huge file. But looking at the file, it might be that the instances info is only sampled once (as expected), but the image sequence has a huge chunk of text for each frame. Is this correct? If so, can I do anything about it? I'm using an image sequence that is duplicated (as instances) about a 100 times (with different start frame) and then feed that into a Texture Switch node in order to randomize the texture for each particle.

Any ideas? Attached is a simple scene that illustrates the problem. Note that the example does not have any alphas, but the setup is still there (as I need it in my actual scene).

[boyan]

Hey, Simon,

Thank you for the feedback,

- In a simple test I had my scene range to be 10-20. But when exporting a .vrscene it seems like it exports frames 0-120 for some reason? If I had my range at 500-600, it seemed like 1-100 was exported, but I guess that it's not using actual frame numbers in that case?

Check the attached file to resolve the issue :








Cheers,

[simonbjork]

Yes, there's no problem when rendering frame ranges via vray cloud. I was just testing different things to reduce the size of a .vrscene file when I saw the odd behavior. So basically I just used File/Export/Vray scene.

[boyan]

You can reduce the vrscene file slightly by using the custom option.

[simonbjork]

Thanks boyan, I'll try to explain what I'm trying to do. There's two separate issues here.

1. First create a new scene, set the scene frame range to 10-20 and go to File/Export As/vrscene. Open vrscene in a text editor and see that it has frames 0-120 exported. I guess that is some kind of bug? Or something about my setup. I only discovered it becuse I was searching in a vrscene to see why there were so huge.

2. The main issue is the size of the vrscene. As I wrote in the original post I have the "This Replicator is Animated" unchecked and from what I can see the transformation of the mesh instances/particles is only read once and saves a lot of space. What makes the vrscene explode in size seems to be that there is a huge chunk of text for each frame with info about the texture map (image sequence in my case). In the end I will have say 100-200 different image sequences in my scene. Is there a way to reduce file size regarding this?

[boyan]

Howdy,

Thank you for the feedback. I've checked your scene file and You have to change the "Scene Range" to 0-200 in order to render correctly the image sequence !!!

You can convert the Replicator to alembic file (*.abc) and next to used it with V-Ray Proxy this will reduce the file size. Make group mask for V-Ray proxy and upload the image sequence.







Cheers,

[simonbjork]

Hi Boyan,

thanks for the suggestion and sorry for the late reply.

Yes, that should work, but there are a number of problems with it. When converting a replicator to a mesh the particle id values are lost so you can't use the Texture Switch to randomize the images. That's seems to be a different problem though, I'll start a new thread regarding that.

[vladimir.nedev]

- In a simple test I had my scene range to be 10-20. But when exporting a .vrscene it seems like it exports frames 0-120 for some reason? If I had my range at 500-600, it seemed like 1-100 was exported, but I guess that it's not using actual frame numbers in that case?

The V-Ray commands will use the animation range defined in the "Frame" tab in the "Render" item. Scene range is not used.

- If I uncheck the "This Replicator is Animated" I still get a huge file. But looking at the file, it might be that the instances info is only sampled once (as expected), but the image sequence has a huge chunk of text for each frame. Is this correct? If so, can I do anything about it? I'm using an image sequence that is duplicated (as instances) about a 100 times (with different start frame) and then feed that into a Texture Switch node in order to randomize the texture for each particle.

Yes, for image sequences each frame in the .vrscene file will store the raw image data for the frame.
I did it this way to avoid having to reproduce the behavior of the /first frame/last frame/fps multiplier/star frame/end behavior/ options in the image sequence tab.

This is highly inefficient especially for your use case, so I've made a note to fix this, not sure when I will be able to do it.

Greetings,
Vladimir Nedev

[simonbjork]

Thanks Vladimir for clearing things up .

Yes, dealing with which frames from a sequence are actually used is a pain (I do it a lot in Nuke). It would be great to have though. I would say first/last and start frame is the most important.

In my case the scene takes about 1.5 hours to export to a vrscene file. On the bright side though, it renders pretty fast and it would have been impossible to render the scene with the modo internal renderer.