ForestPack display count doesn't work with limit to visibility enabled

[ZO6039]

I have a ForestPack setup for the grass. I have Limit to visibility enabled. And when I have it enabled I cannot control display count in viewport. I have 2.8M particles visible in viewport, even if I set display count to 500. I have density 100 pixels for 15 meters. Display count starts to work when I change density from 15 meters to 20 meters and more. But I need it at 15 meters. It means I have to suffer from slow viewport update with all 2.8M particles visible. I have no idea why it works is such a weird way. I need a help, please.

[Michal Karmazín]

Hi,

I have just done some tests with Forest Pack 8.2.6, but so far, I cannot reproduce the reported problem - it seems to work just fine in my quick tests. Please find attached the sample scene (240404_limitToVisibilityMax_iToo.max). If possible, feel free to send us your scene - preferably simplified and containing only the problematic object(s) - ideally, if you can reproduce it on a minimal scene, it would be greatly appreciated. Thanks in advance.

Best regards,

[ZO6039]

I was able to simplify the scene. Here is the 3ds Max 2024 file with problematic FP attached.

[Michal Karmazín]

Thanks for your swift reply and the provided scene. It has to be investigated more deeply by our main developers. Let me mention, that the 'Max Item' value in the Viewport does not accurately count the exact number of items and discard them because that is not suitable and efficient for a multithreading approach. Instead, it makes an estimation of the possible number of items that will be generated and adjusts the density values to get an approximate result. In this case, it appears that the combination of parameters in your scene (it's a really large area) leads to an inaccurate estimation of the needed Density value. You may consider enabling the object only at the render time.

Best regards,

[ZO6039]

Thank you for your suggestion. But I cannot find how to enable FP object at the render time only. Could you point me to the right direction, please?

[Michal Karmazín]

You can simply hide it (for example, by using the Hide Selection) or use the Forest Lister for these purposes to manage the Display - Build - Disable Object option (accessible also by Maxscript $.disabled = on / $.disabled = off). I hope that helps.

Best regards,

[ZO6039]

Ah, ok, this what I usually do. But I thought there is a checkbox in FP somewhere to keep FP hidden until render.