Transformation history

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Danny
Posts: 3
Joined: Tue Jun 28, 2016 1:24 pm

Transformation history

Post by Danny »

Hi,
I'm looking for some help on interpreting the transformation history parameters. It is quite obvious to me to actually get the transformation matrix and associated info while performing scans registration, but why in the case of shape detection/fitting using the RANSAC plugin? Say a shape is detected and fitted on a cylindrical point cloud segment, selecting the shape entity will provide a transformation history in the properties window. Since the shape is detected and fitted as close to the cloud segment as possible, why would such a transformation would take place? Can you provide me more info about those parameters (Axis, Angle, Center) and how I can relate them to the shape thats been fitted?

Thank you sir
daniel
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Re: Transformation history

Post by daniel »

Oh, that's because internally when a geometric entity is created, it is always in a default orientation (e.g. cylinder's axis is along Z, etc.). Then we have to transform them so as to place them at the right position in space in the case of qRansacSD.

But I agree, from a user point of view we could reset the transformation history.
Daniel, CloudCompare admin
Danny
Posts: 3
Joined: Tue Jun 28, 2016 1:24 pm

Re: Transformation history

Post by Danny »

Hi,

Since this transformation history is directly related to how the shape was fitted, personnally, I think it should remain since it provides other parameters to better describe the geometry and cartesian state of the actual shape.

Thank you
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