[vtk-developers] [VTK 0012659]: BUG in vtkCellLocator::FindCellsAlongLine

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://vtk.org/Bug/view.php?id=12659 
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Reported By:                Bryn Lloyd
Assigned To:                
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Project:                    VTK
Issue ID:                   12659
Category:                   (No Category)
Reproducibility:            have not tried
Severity:                   minor
Priority:                   normal
Status:                     backlog
Project:                    Release 
Type:                       incorrect functionality 
Resolution:                 open
Fixed in Version:           
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Date Submitted:             2011-10-15 17:35 EDT
Last Modified:              2011-10-15 17:35 EDT
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Summary:                    BUG in vtkCellLocator::FindCellsAlongLine
Description: 
I think I have found a bug in vtkCellLocator, which is very similar to a bug,
which already was fixed previously at a different location:

http://www.vtk.org/gitweb?p=VTK.git;a=commitdiff;h=07a9667a44194de355ece2380d00436c0d528bcf

There is a missing "tMax = sqrt( tMax );" after the for loop, which computes
tMax (around line 1850)
 

This bug was fixed in the function IntersectWithLine in September 2008, by
Zhanping Liu. But the fix was not applied to the function FindCellsAlongLine.


I was searching for the reason why a cell intersection was not found, even
though there should have been several intersections. It seemed unlikely to be
related to numerical accuracy (nearly equilateral triangles, intersection nearly
in center of triangle, perpendicular to triangle). After adding the missing
sqrt, the intersections were found correctly.

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Issue History 
Date Modified    Username       Field                    Change               
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2011-10-15 17:35 Bryn Lloyd     New Issue                                    
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