CloudCompare forum

Hello everyone!

I have some issue, which I would want to understand more about.
I made 2 videos showing what I mean.
In general - when I open PCloud (LiDAR scan) it works flawless w/o any delay or refreshing, the gray wheel in the upper left view corner is frozen, w/o spinning (as visible).
After some time, without even doing anything, the wheel starts rotating and the cloud is being refreshed, and then each time I change the view or pan around - it is being refreshed.
I have read something about "decimation" option etc. but I am not familiar.
I have experience in CCompare in working for reducing and filtering out noise etc. but so far I have never questioned or had ideas of going deeper how it works exactly. Now I already do.

Files:
https://sunotecgroupcom-my.sharepoint.c ... Q?e=yJWgjS

CCompare version: 2.12.4 (Kyiv)
64GB RAM
4070Ti
AMD 7950x

So I saw what is going on in the background, attached the two pictures..

Seems like it's the LoD accel. structure which after being prepares starts refreshing as I explained..
I do not know, and am not familiar with what it is.

daniel wrote: ↑Sun May 22, 2022 8:43 pm Not sure to understand: if you disable the 'LoD' option (uncheck the checkbox in front of 'When moved, ...'), then you should stay in the initial state you were in (when you said 'after the cloud is loaded into the program, there will be no issues with the framerate when rotating, panning, zooming etc. ').

And the LoD structure won't be computed. Technically, there's no need to fit the whole cloud in VRAM (CC will store what it can, and it will keep the rest in standard RAM).

I found the quoted text from the same situation in another thread.
Trying to do so works constantly, but with not good performance - about 11fps, and not close to what initially is, before LoD computation finishes.

What you experience is the LoD (Level of Detail) mechanism that triggers for large clouds. The definition of 'large' is quite small, only 10 million points by default, but you can change that in the 'Display > Display settings' dialog, with the option 'When moved, decimate cloud over XXX points'.

This is to prevent old graphic cards to be unresponsive or too laggy. Only parts of the cloud are displayed each time, so that the GUI remains responsive. If you have a very good graphic card, don't hesitate to disable this option.