Some plants are fighting for the place on ground (flickering) in animation

[ZO6039]

Sometimes I have a problem with scattered plants where some of plants are flickering during animation, like they are fighting for the place on ground. I need a clue to figure out what could cause such behavior. I have Collisions enabled in Distribution for the trees. Could it be that there is not enough accuracy to calculate position of the tree for the big terrain because my scene system units are in Meters? Or is this distribution map problem (Distribution Density Threshold 5%)?  Or is this something else? I am having such issue in different scenes, not all the time but often enough to make me sad. I use VRayProxy for the trees. The current FP version is 9.0.8b.

[Michal Karmazín]

Hi,

I'm sorry to hear that you're experiencing these difficulties. I would recommend switching to the Custom Edit mode, as the issue may be related to surface evaluation. Please use the Surface > Place Items button and try disabling the Surface > Non-Image modes - Link to surface checkbox to see if that resolves the issue.

Additionally, I want to mention that you should avoid using the Camera - Distance Falloff feature when rendering walk-through animations. This feature can cause sudden appearance or disappearance of items due to changes in camera distance during motion, as stated in our online reference guide.

Thank you in advance for any further comments you can share about this issue with us or our user community, in case other users encounter similar problems.

Best regards,

[ZO6039]

I do not use Camera - Distance Falloff for the trees. When I switch from Generate to Custom Edit mode I have a different density of scattered objects, what makes render look very different and I cannot control density in Custom Edit mode. See files attached. Custom Edit is not equal Generate, it works absolutely different. You say it might be a surface evaluation, but I don't understand why there is a difference in objects placement in Generate mode in different frames. The surface doesn't change between frames. There are might be some accuracy calculations. This is a big issue which makes ForestPack hard to use for animations. I had never had such issues with Multiscatter plugin. If objects were placed, they were placed same way in each frame. Could it be a problem that I have Auto update switch turned on for surfaces, or it doesn't make difference if I render on render farm with different computers? Should I try use UV mode instead of XY for surfaces?

[Michal Karmazín]

It sounds like some items may be hidden from the viewport to optimize performance. Please try disabling any viewport limits in the Display rollout before switching to Custom Edit mode by setting the limits to 0. This should ensure there’s no difference. If you have any further troubles with it, please feel free to send us your scene and we'll check it. Thank you in advance.

Best regards,