mesh scaling and orientation tools - suggestion

[AndrewRabbitt]

Using Meshlab for engineering-type work with 3D scans of "mechanical" type objects, getting the scale and orientation accurate is something I've not managed well yet with Meshlab. I'd like to suggest a couple of tools that would help - maybe they already exist and I'm not aware of them, but if not here's an idea.

I'd like to be able to select and isolate a subset of cloud points from a scan that represent a plane, a sphere, a cylinder etc. and then define the orientation, scale, diameter of a reference plane/sphere/cylinder that generates from a least-squares algorithm a scaling, vector offset and rotation matrix. Each feature can generate its individual scale+rotation+offset and then these matrices can be averaged and applied to the base mesh as a final operation.

This is kind of like the Align tool, but where scale information is not assumed but driven by "known" features from the original geometry.

By way of example:

With this gearbox casing, I want to be able to orient based on the flange face surface data, scale based on diameter and position of selected mounting hole cylinders and position the origin to the input shaft bearing cylinder. This process may need several
"stages" to make the computation easy.

Tell me how I could do this with the current Meshlab tools, or take this suggestion for what it's worth.

[AndrewRabbitt]

Hmmm. It seems that a regression of a cylinder point cloud to a cylinder is not the easiest thing in the world.