Issue with zoom sensitivity in perspective mode

[mapdeep]

I've noticed that when I import a georeferenced point cloud (with shifted coordinates), I have trouble navigating very close to ground level in perspective mode. Basically, if I'm near the ground, if I try to zoom in just a bit (one little turn of the scroll wheel on the mouse), this corresponds to moving perhaps 100 meters. If I change the view mode to orthographic, the scroll wheel acts normally again. The point cloud model I am importing is on the order of 5 km long - I'm not sure if this has to do with the issue.

Is there a way to change the mouse's zoom sensitivity in perspective mode? If not, can I zoom in another way other than using a mouse that may perhaps be less sensitive in perspective mode?

Thank you

[daniel]

I think the issue you encounter is sadly the 'standard' behavior in Perspective mode.

Actually the wheel mouse is used to zoom (in and out) and not to 'move' around the cloud. So we simply move the camera of a percentage of the total bounding-box (quite big actually as the aim is to zoom in and out without requiring too many wheel turns).

I guess we could be smarter... not sure how however ;)

[mapdeep]

Hi Daniel,

Thanks for the reply. Given that you move the camera based on a percentage of total bounding box, it makes sense that I am experiencing zoom sensitivity; I have a very large bounding box. I suppose a workaround for me would be to prepare sub-sample data sets that don't have such a large extent.

In terms of an eventual CloudCompare solution: if I could, on the fly, change the extents of the data set (in other words, do a temporary "clip" by area), I wouldn't need to prepare my sub-sample data sets. I remember there was some discussion on the forms about this ability to temporarily clip the data extents as a potential future enhancement but I forget the exact terminology that was being used to describe this functionality, or if this conversation actually happened in these forums.

Does this functionality already exist by chance / if not, are there plans for it, or perhaps other functions that might be similar?

Thanks for all your work

[daniel]

Indeed, there's a 'Cross Section' tool now (http://www.cloudcompare.org/doc/wiki/in ... ss_Section). But sadly you won't be able to 'process' the cloud while in this mode (so it won't solve your issue).

I've added in the 'Display properties' a new option to set the zoom speed in perspective mode. Default speed is 1.0, but you can set it between 0.001 (to go much slower) and 1000.0 (much faster). You can test this with the latest beta release (see the 'Download' section of http://www.cloudcompare.org).

[mapdeep]

Your new zoom speed in perspective mode option works great! Many thanks - I'm now able to explore my point cloud with much great ease.