OTOY Forums

Hi All,
Am I correct thinking that Strands and Motion blur don't work ?
I have seen that you can add geometry to a strand and then render, but in the case of grass etc that would get heavy. Will instancing help in this case and if so are there any examples ?
Also I have tried Motion blur but cannot seem to get good results ... my camera is moving through the scene by the way. I cannot seem to find any good documentation or examples.
I think that both of these are needed on a daily basis throughout the industry .... Please help
Thanks

Each strand can be individual, so it is nearly impossible to check, if one strand is the same as another.
As example, you have 20.000 deformed strands. Now check each strand with another if they are equal.
Maybe you find 100 strands which are equal. For this strands you can create instances.
The time you need to do this should be greater than the export time and you must also export the rest of 19900 strands. The file isn´t realy smaler.

Better is to use a group of different grass meshes and emit they with different positions and orientations to your landscape.
So you have maybe 20 different meshes with 1000 instances each.
This can be done with the exporter, if it is ready...


The motion blur is tricky.
You can try to use another aperture if you move the camera, so the objects which are out of focus are blurred more.
Or render out a motion vector pass and use you favorite composing tool.

face

Hi face,
Thanks for getting back to me so quickly !
Will strands ever be renderable in Octane ? If not then I already have a reasonable solution similar to the one posted here using an image with alpha channel etc. Just wondered though if strands will ever be available to us as that would be special !
As for Motion blur ... it seems completely unpredictable for now BUT a real timesaver if you guys could fix it. I think your motion blur would be quicker in a lot of cases that in comp.

Yes, strands are special.
They are only curves which are send to mental ray with the shape they should have.
That was the problem which i had to solve. But the conclusion is, my strand meshes are better than the rendered MR ones

face

Hi face, have you tried Zybrand Grass ?
It's so quick and easy to render, but converting it polygons and sending it over to Octane would be very heavy, no ?

Too heavy i think.

face

Hi face,
So if I understand you ... there is no way to render strands directly without making them polygons ...

Correct, strands are only curves and Octane can´t render curves.

face

Hot Dang !
Oh well, I really appreciate your work though ... Great job on what's possible.
If you could ever somehow change that you would win a lot people me thinks

Thanks for setting the record straight
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