Calculating 'real' volume/area?

[Kwanmok]

To all,

I am trying to calculate the true volume or surface area of a small object, a size of a 1liter water bottle.
I did turn my point cloud to a mesh and calculated both the volume and surface area however, since my mesh(or point clouds) didn't have a coordinate system (since it is so small and I don't have to compare it with anything), the numbers presented from Cloudcompare doesn't give me any units..

So my questions is..
1) In this case, do I need to set up a coordinate system to have the real measures? Then, how can I do this?
2) Can I do this in Cloudcompare or do I have to set this coordinate (or real size scale) from a different program and them import in CC?

3) Although off topic from number 1 and 2, I am trying to tilt the original axis of my point cloud. How do I do this?

Thanks in advance.

[daniel]

To scale an entity, you have basically two choices:
- either you only know some particular dimensions of your object, and then you can use the 'point picking tool' and the 'Edit > Multiply/Scale' tools together (see http://www.cloudcompare.org/doc/wiki/in ... e_entities)
- or you have more accurate information, and then you can use the 'Tools > Registration > Align' tool and input the real coordinates of multiple points to get a more robust scale (and coordinate system)

[daniel]

Oh, and to change the orientation of a cloud, you can either do it manually (with the 'Edit > Translate and Rotate' tool), or you can input a given rotation matrix ('Edit > Apply Transformation'), and you can also 'level' a plane so it becomes parallel to (XY) (with 'Tools > Level').

See the wiki for more information about these tools.