Aligning fragments

[chavdar]

Hi everyone,

I have a stone block broken in two. Each part is scanned as a point cloud and I am trying to align the two clouds together so that the two pieces join (as if I am joining the actual stones). I can align them manually but this would be far from accurate since there is no way to see how the broken surfaces "touch" each other.
Is there a tool that can help me find the best possible alignment?

Many thanks!

[daniel]

You should actually use the ICP registration tool (https://www.cloudcompare.org/doc/wiki/i ... ?title=ICP).

You should start by manually make the two parts close to each other.

Then segment the touching part (with the scissors tool) from one cloud. And align it with the other part (with the ICP tool).

Then copy the resulting matrix (from the Console) and apply it to the remaining part (with 'Edit > Apply transformation'). You can eventually merge the two parts back together (select the two parts and use 'Edit > Merge').

[chavdar]

Many thanks for your reply. I tried it but it does not work well, probably because the surfaces were damaged during the breakage and do not match perfectly.

[daniel]

If you want me to double check, don't hesitate to send me the clouds so that I can try on my side (admin [at] cloudcompare.org).