Difference between revisions of "Fit Quadric"

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Select one or several point clouds then launch this tool.
 
Select one or several point clouds then launch this tool.
  
For each cloud CloudCompare will fit a 2.5D Quadric (the cloud is first projected on its best fit plane).
+
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).
  
 
[[Image:Cc_fit_quadric_example.jpg|frame|center|Fitted quadric (+ distances between the original cloud and the fitted quadric)]]
 
[[Image:Cc_fit_quadric_example.jpg|frame|center|Fitted quadric (+ distances between the original cloud and the fitted quadric)]]
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In the console the following pieces of information will be output:
 
In the console the following pieces of information will be output:
* the 6 quadric equation coefficients (''a + b.x + c.y + d.x<sup>2</sup> + e.y<sup>2</sup> = 0'')
+
* the 6 quadric equation coefficients (''a + b.x + c.y + d.x<sup>2</sup> + e.xy + f.y<sup>2</sup> = 0'')
 
* the quadric fitting [http://en.wikipedia.org/wiki/Root_mean_square RMS]
 
* the quadric fitting [http://en.wikipedia.org/wiki/Root_mean_square RMS]
  

Revision as of 03:47, 2 September 2016

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 (a + b.x + c.y + d.x2 + e.xy + f.y2 = 0)
  • 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.')