Instance Motion Blur with Node controlled instances Tweet

[baltort]

Hi,

I'm struggling to get any motion blur from instances that are being animated via the nodes panel of the instance generator. LW render is showing the blur correctly. It even shows up in the LW viewport when MB preview is turned on, but it doesn't show in IPR or an f9/F10 render.

Cranking up the number of instance motion blur samples doesn't seem to have any effect.

Any ideas?

Cheers,

James.

[juanjgon]

Hi,

I remember some limitations in the LW SDK related to the instances motion blur if the base mesh has animated deformations, but I'm not sure if this could be also your problem.

Can you please attach a sample scene using your workflow to test it here?

Thanks,
-Juanjo

[baltort]

Sure thing.

Please see attached...

[juanjgon]

Your scene seems to work fine here. The problem can be that the instances motion blur can't be rendered in the IPR window due to some limitations in the LightWave SDK, but the final F9/F10 should work fine. Can you please check it again?

To animate the object you are using a node that I don't have here AsMs_Time, so I'm adding an animated parameter to replace it, but I suppose that this node should work fine also.

Thanks,
-Juanjo

[juanjgon]

On thing, please set the number of MB time slices to 2 in the LW instancer, and also set the render target instances motion blur steps to 2 ... it is enough, and should work better.

Thanks,
-Juanjo

[baltort]

Thanks juanjgon,

That's strange. You're seeing what I expected. I've also replaced the time node with an animated scalar, but still no joy.

This is the result of an f9 render for me:

Any ideas?

Thanks,

James.

[juanjgon]

Have you set the mb time slices to 2 in both places (the lw instancer and the plugin render target mb options)? I think that this is the only change I have made.

Attached you have my scene, that should work fine.

Thanks,
-Juanjo

[baltort]

Thanks Juanjo,

This is strange... The file you sent over doesn't appear to have any instance nodes in it. Could it be a LW version issue? I'm in LW 11.6.3

[juanjgon]

Ok. This can be the problem. I've been checking your scene in LightWave 11.6 and it seems that in this LightWave version the motion information from the node editor is not available in the instancing API, so it is not available for the external renderers.

Sorry, it seems an issue fixed in LW2015.3, but a limitation not fixed in the LW 11.6 ... I'll investigate this issue a little more, but I'm afraid that it is going to be hard to fix because it seems a problem in the LightWave SDK side.

Thanks,
-Juanjo

[juanjgon]

In any case, if you need to render this scene with motion blur, you could use the old multipass motion blur feature:
https://docs.otoy.com/manuals/products/ ... tion-blur/

Thanks,
-Juanjo