Why do I get this error with the pc2surfacemesh function? Please help!

Hello, everyone!

I'm working on a surface reconstruction problem for a data-heavy point cloud with 200 million points. I am using the statement mes= pc2surfacemesh(ptCloud, "ball-pivot",5);in matlab to reconstruct it.However it reported an error and I don't understand what it means:

Caught "std::exception" Exception message is:

QH5 qhull precision error (qh_mergefacet): wide merge for facet f1880216 into f1880213 for mergetype 7 (ridge). maxdist 0 mindist -5.9e-06 vertexdist 1.4 Allow with 'Q15' (allow_widemax)

ERRONEOUS FACET:

- f1880216

- flags: top newfacet dupridge mergeridge2

- normal: 0.02265 0.9334 -7.061e-06 -0.3581

- offset: -3244331

- vertices: p1918557(v86219) p1918273(v86217) p1863371(v35396) p1918111(v21244)

- neighboring facets: f1259936 f1880217 f1880213 f1880215

- ridges:

- r1178601 tested simplicialtop

vertices: p1918273(v86217) p1863371(v35396) p1918111(v21244)

between f1880216 and f1259936

- r1178623 simplicialtop simplicialbot

vertices: p1918557(v86219) p1863371(v35396) p1918111(v21244)

between f1880217 and f1880216

- r1178624 simplicialtop

vertices: p1918557(v86219) p1918273(v86217) p1918111(v21244)

between f1880216 and f1880213

- r1178625 simplicialtop simplicialbot

vertices: p1918557(v86219) p1918273(v86217) p1863371(v35396)

between f1880215 and f1880216

ERRONEOUS OTHER FACET:

- f1880213

- flags: bottom newfacet dupridge mergeridge1

- normal: 0.02265 0.9334 1.794e-05 -0.3581

- offset: -3244330

- vertices: p1918557(v86219) p1918273(v86217) p1915947(v57675) p1918111(v21244)

- neighboring facets: f1880145 f1880218 f1880207 f1880216

- ridges:

- r1178620 simplicialtop simplicialbot

vertices: p1918273(v86217) p1915947(v57675) p1918111(v21244)

between f1880145 and f1880213

- r1178621 simplicialtop simplicialbot

vertices: p1918557(v86219) p1915947(v57675) p1918111(v21244)

between f1880213 and f1880218

- r1178622 simplicialtop simplicialbot

vertices: p1918557(v86219) p1918273(v86217) p1915947(v57675)

between f1880213 and f1880207

- r1178624 simplicialtop

vertices: p1918557(v86219) p1918273(v86217) p1918111(v21244)

between f1880216 and f1880213

While executing: | qhull d Qbb Qt

Options selected for Qhull 2018.0.1.r 2018/12/28:

run-id 1504989550 delaunay Qbbound-last Qtriangulate _pre-merge

_zero-centrum Pgood _max-width 1.5e+03 Error-roundoff 4e-09

_one-merge 3.6e-08 _near-inside 1.8e-07 Visible-distance 2.4e-08

U-max-coplanar 2.4e-08 Width-outside 4.8e-08 _wide-facet 1.4e-07

_narrow-hull 3.2e-10

Last point added to hull was p1918557. Last merge was #289071.

At error exit:

Delaunay triangulation by the convex hull of 2158853 points in 4-d:

Number of input sites: 86193

Total number of deleted points due to merging: 26

Total number of nearly incident points: 2072634

Number of Delaunay regions: 0

Number of non-simplicial Delaunay regions: 64365

Statistics for: | qhull d Qbb Qt

Number of points processed: 86219

Number of hyperplanes created: 1742992

Number of facets in hull: 422979

Number of distance tests for qhull: 315275859

Number of distance tests for merging: 15476643

Number of distance tests for checking: 0

Number of merged facets: 293734

Maximum distance of merged point above facet: 4.1e-07 (10.5x)

Maximum distance of merged vertex below facet: -1.1e-06 (27.4x)

precision problems (corrected unless 'Q0' or an error)

500 flipped facets

95326 coplanar horizon facets for new vertices

6 degenerate hyperplanes recomputed with gaussian elimination

6 nearly singular or axis-parallel hyperplanes

42 ridges with multiple neighbors

I'm asking for help, I'm not sure if the number of point clouds is too large or if it's caused by noise?

Thanks in advance!

Huang Zelin

[Nitin Kapgate]

Hi Zelin,

I couldn't reproduce the error without your data. If possible, could you please share the point cloud data so that we can reproduce and analyze the problem?

Thanks,

Nitin