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IDProjectCategoryView StatusDate SubmittedLast Update
0005519VTK(No Category)public2007-08-16 14:372016-08-12 09:54
ReporterRandallHand 
Assigned ToLisa Avila 
PrioritynormalSeveritytweakReproducibilityalways
StatusclosedResolutionmoved 
PlatformOSOS Version
Product Version 
Target VersionFixed in Version 
Project
Type
Summary0005519: Blank-Lines in vtkFixedPointVolumeRayCastMapper Renderings
DescriptionWhen rendering Volume-Render images with the FixedPoint mapper and the Image is aligned to the viewing direction, planes parallel to the viewing vector exhibit black lines. however, the lines only obscure the distant part of the volume, as if the rays terminate early.

This is caused by accuracy problems in the "numSteps" computation in ComputeRayInfo. When dir approaches 0, but is not exactly equal to zero, that numSteps number is incorrectly computed significantly shorter (30-50%) than it should be, causing the rays to terminate midway through the volume.

The attached patch recomputes the ray direction after the number of steps has been calculated to ensure the ray will fully traverse the volume.
Steps To Reproduce
Additional InformationDiscussed in the VTK-Developers mailing list

http://public.kitware.com/pipermail/vtk-developers/2007-August/004678.html [^]
http://public.kitware.com/pipermail/vtk-developers/2007-August/004680.html [^]
http://public.kitware.com/pipermail/vtk-developers/2007-August/004681.html [^]
TagsNo tags attached.
Relationships
Attached Filespatch FixedPoint.patch (1,593) 2007-08-16 14:37
https://www.vtk.org/Bug/file/6109/FixedPoint.patch
Issue History
Date ModifiedUsernameFieldChange
2007-08-16 14:37RandallHandNew Issue
2007-08-16 14:37RandallHandFile Added: FixedPoint.patch
2007-08-17 08:20Berk GeveciStatusbacklog => tabled
2007-08-17 08:20Berk GeveciAssigned To => Lisa Avila
2011-06-16 13:11Zack GalbreathCategory => (No Category)
2016-08-12 09:54Kitware RobotNote Added: 0036926
2016-08-12 09:54Kitware RobotStatusexpired => closed
2016-08-12 09:54Kitware RobotResolutionopen => moved

Notes
(0036926)
Kitware Robot   
2016-08-12 09:54   
Resolving issue as `moved`.

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