viewing 20M+ pointcloud in UTM coordinates

[Kjellis85]

This is not specifically related to photoscan, but it might apply to other's who are having the same problem as me.

My problem is a pointcloud from a laser scan done that is in the region of 20M+ points. I am trying to view it using the freeware meshlab (since I do not have access to any other 3d viewing software) but is unable to view it due to the fact that the x y z values are too large (7772465.221313, 348256.165845, 58.21354). I have managed to remove the first four digits, but unable to move the decimal point so that the numbers will be between 1 and 0. Does anyone have any tips on how to relocate the decimal point? Or are there any other solutions that are better?

[photogrammetrix]

Hi,

you may like to try CloudCompare. It is OpenSource and free.

http://www.danielgm.net/cc/release/

CloudCompare is a nice tool in addition to meshlab and it shifts coordinates temporarely and gives you a notice about it. 2o Mio points should be possible with it.

Cheers

[Kjellis85]

I did try Cloud compare and it works great for viewing the model in it self, but I haven't figured out how to transform the coordinatevalues permanently in cloud compare so that I can use it in Meshlab.

However, I feel that this might start to trail too much off topic for this to be a photoscan-forum issue, so I investigate this further elsewhere.

[photogrammetrix]

Hi,
I also have not digged too deep into cludcompare yet and did not test the following:

when you select  the pointcloud in the list of data objects you can open from Edit menu a dialog to apply a transformation matrix. Try with editing TX,TY,TZ  to fit to your needs.

Hope it will work...

Cheers

[photogrammetrix]

just have overlooked that in the same edit menu there is also an option to scale your data.

Cheers

[phisan]

JAG3D is the official tool to do the job. It can do translation Tx,Ty,Tz
but i doubt , would it work with 20+ M point cloud.
If it has command-line not GUI , you will be lucky.

http://javagraticule3d.sourceforge.net/

Second way, grab Python and liblas , hack a bit and do simple
calculus ...
x = x+Tx
y = y+Ty.

Br,
Phisan