Fit Quadric

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Menu

This tool is accessible via the 'Tools > Fit > 2.5D Quadric' menu.

Description

This tool fits a 2.5D quadric on a point cloud.

Procedure

Select one or several point clouds then launch this tool.

For each cloud CloudCompare will fit a 2.5D Quadric (a plane is fitted first on the cloud so as to determine the 'most flat' dimension).

Fitted quadric (+ distances between the original cloud and the fitted quadric)


In the console the following pieces of information will be output:

  • the 6 quadric equation coefficients: z = a + b.x + c.y + d.x2 + e.xy + f.y2 (mind that depending on which is the 'most flat' dimension, 'x', 'y' and 'z' can be permuted)
  • the quadric fitting RMS


Notes:

  • the fitted quadric is added to the DB tree as a child of the cloud
  • the quadric is represented as a standard triangular mesh. Therefore you can select both the cloud and the fitted quadric and compute the distance between them (with 'Tools > Distances > Cloud/Mesh Dist.')