mili zbuffer thrashing test failure (started in VTK-8)

[aowen87]

This is a bit of an odd test case but I think mili database is serving up a mesh with two surfaces that are defined by the same points. So, the surfaces fall on top of each other. Old VisIt would still draw this correctly. New VisIt manifests zbuffer thrashing. Also seen in moab_02 test in serial mode and in parallel mode. http://portal.nersc.gov/project/visit/tests/20180514-22:00/surface_trunk_serial/databases_mili.html

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Ticket number: 3082 Status: New Project: VisIt Tracker: Bug Priority: Normal Subject: VTK8 - mili zbuffer thrashing test failure Assigned to: - Category: - Target version: 3.0 Author: Mark Miller Start: 05/02/2018 Due date: % Done: 0% Estimated time: Created: 05/02/2018 04:42 pm Updated: 05/17/2018 01:56 pm Likelihood: 3 - Occasional Severity: 4 - Crash / Wrong Results Found in version: trunk Impact: Expected Use: OS: All Support Group: Any Description: This is a bit of an odd test case but I think mili database is serving up a mesh with two surfaces that are defined by the same points. So, the surfaces fall on top of each other. Old VisIt would still draw this correctly. New VisIt manifests zbuffer thrashing. Also seen in moab_02 test in serial mode and in parallel mode. http://portal.nersc.gov/project/visit/tests/20180514-22:00/surface_trunk_serial/databases_mili.html

Comments:

[brugger1]

This is from a filled boundary plot of mili_test_data/m_plot.mili. I have attached before and after images. The top image is the new one. In the old image the layer of green shell elements is completely missing and a layer of yellow shell elements that are behind the 2 layers of hexes are completely visible with no z buffer thrashing. In the new image there is z buffer thrashing with the green shell elements and if you looked at the other side you would see z buffer thrashing with the yellow shell elements.