Fit Quadric - Revision history

Daniel: /* Procedure */

2016-09-02T09:49:43Z

Procedure

← Older revision		Revision as of 11:49, 2 September 2016
Line 17:		Line 17:

	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.xy + f.y<sup>2</sup> ~~= 0~~'')		* the 6 quadric equation coefficients: ''z = a + b.x + c.y + d.x<sup>2</sup> + e.xy + f.y<sup>2</sup>'' (''mind that depending on which is the 'most flat' dimension, 'x', 'y' and 'z' can be permuted'')
	* the quadric fitting [http://en.wikipedia.org/wiki/Root_mean_square RMS]		* the quadric fitting [http://en.wikipedia.org/wiki/Root_mean_square RMS]

Daniel: /* Procedure */

2016-09-02T09:47:00Z

Procedure

← Older revision		Revision as of 11:47, 2 September 2016
Line 11:		Line 11:
	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)]]
Line 17:		Line 17:

	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]

Daniel: /* Procedure */

2015-02-20T13:23:54Z

Procedure

New page

= 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 (the cloud is first projected on its best fit plane).

[[Image:Cc_fit_quadric_example.jpg|frame|center|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.x<sup>2</sup> + e.y<sup>2</sup> = 0'')
* the quadric fitting [http://en.wikipedia.org/wiki/Root_mean_square 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-to-Mesh Distance | Cloud/Mesh Dist.]]')