Difference between revisions of "Compute geometric features"
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(Created page with "= Menu = This tool is accessible via the 'Tools > Other > Compute geometric features' menu. = Description = This tool allows to computation several geometric features on one...") |
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Geometric features that can be computed this way are: | Geometric features that can be computed this way are: | ||
− | * Roughness | + | * Roughness |
+ | ** equivalent to the former [[Roughness]] tool of v2.9 and below | ||
+ | ** in version 2.12, an option allows to compute signed roughness values based on a 'up vector' | ||
* Curvature (equivalent to the former [[Curvature]] tool of v2.9 and below) | * Curvature (equivalent to the former [[Curvature]] tool of v2.9 and below) | ||
** Mean curvature | ** Mean curvature | ||
Line 26: | Line 28: | ||
** PCA 1 | ** PCA 1 | ||
** PCA 2 | ** PCA 2 | ||
− | |||
** Surface variation | ** Surface variation | ||
** Sphericity | ** Sphericity | ||
Line 34: | Line 35: | ||
** 3rd eigenvalue | ** 3rd eigenvalue | ||
− | ''' | + | '''Notes: |
+ | * most of the above features are defined in [https://ethz.ch/content/dam/ethz/special-interest/baug/igp/photogrammetry-remote-sensing-dam/documents/pdf/timo-jan-cvpr2016.pdf "Contour detection in unstructured 3D point clouds", Hackel et al, 2016'''] | ||
+ | * curvature formulas computed from a local quadric function come from: "Three-dimensional surface curvature estimation using quadric surface patches", I. Douros and B. Buxton, University College London | ||
+ | * roughness computation algorithm is described in the old [[Roughness]] tool description page | ||
= Procedure = | = Procedure = | ||
Line 47: | Line 51: | ||
Then choose the geometric feature(s) that should be computed (several features can be selected/checked at the same time). | Then choose the geometric feature(s) that should be computed (several features can be selected/checked at the same time). | ||
− | + | Notes: | |
+ | * currently each feature is computed independently. The extraction of the local neighborhood is sadly not leveraged for all the features... | ||
+ | * since version 2.12, an option allows to define a 'up direction' to compute signed roughness values | ||
== Output == | == Output == | ||
On success, CC will compute the selected features one by one and create a scalar field for each. | On success, CC will compute the selected features one by one and create a scalar field for each. |
Latest revision as of 14:57, 2 January 2025
Menu
This tool is accessible via the 'Tools > Other > Compute geometric features' menu.
Description
This tool allows to computation several geometric features on one or several point clouds (in a batch).
Geometric features that can be computed this way are:
- Roughness
- equivalent to the former Roughness tool of v2.9 and below
- in version 2.12, an option allows to compute signed roughness values based on a 'up vector'
- Curvature (equivalent to the former Curvature tool of v2.9 and below)
- Mean curvature
- Gaussian curvature
- Normal change rate
- Density (equivalent to the former Density tool of v2.9 and below)
- Number of neighbors
- Surface density
- Volume density
- Moment
- 1st order moment
- Features
- Sum of eigenvalues
- Omnivariance
- Eigenentropy
- Anisotropy
- Planarity
- Linearity
- PCA 1
- PCA 2
- Surface variation
- Sphericity
- Verticality
- 1st eigenvalue
- 2nd eigenvalue
- 3rd eigenvalue
Notes:
- most of the above features are defined in "Contour detection in unstructured 3D point clouds", Hackel et al, 2016
- curvature formulas computed from a local quadric function come from: "Three-dimensional surface curvature estimation using quadric surface patches", I. Douros and B. Buxton, University College London
- roughness computation algorithm is described in the old Roughness tool description page
Procedure
Select one or several point clouds then launch this tool.
A dialog will appear:
Then set the 'Local neighborhood radius' on which the selected features will be computed.
Then choose the geometric feature(s) that should be computed (several features can be selected/checked at the same time).
Notes:
- currently each feature is computed independently. The extraction of the local neighborhood is sadly not leveraged for all the features...
- since version 2.12, an option allows to define a 'up direction' to compute signed roughness values
Output
On success, CC will compute the selected features one by one and create a scalar field for each.