On Tue, Jun 25, 2024 at 4:50 AM onur.notonur via petsc-users < [email protected]> wrote:
> Hi, I'm trying to implement a Tetgen mesh importer for my > Petsc/DMPlex-based solver. I am encountering some issues and suspect they > might be due to my import process. The Tetgen mesh definitions can be found > here for reference: https: //wias-berlin. de/software/tetgen/fformats. > htmlI > ZjQcmQRYFpfptBannerStart > This Message Is From an External Sender > This message came from outside your organization. > > ZjQcmQRYFpfptBannerEnd > Hi, > > I'm trying to implement a Tetgen mesh importer for my Petsc/DMPlex-based > solver. I am encountering some issues and suspect they might be due to my > import process. The Tetgen mesh definitions can be found here for > reference: > https://urldefense.us/v3/__https://wias-berlin.de/software/tetgen/fformats.html__;!!G_uCfscf7eWS!fZrK2yb2VL8fOhEwFSop4QgqPuB1M2_C1OMkfebpI6V32422apR69VnseJBVL8CTE5Gn4r6jRSz7K8CgmdZe$ > > <https://urldefense.us/v3/__https://wias-berlin.de/software/tetgen/fformats.html__;!!G_uCfscf7eWS!c6srXdHHqgkq5FoeJpfHljLrP0U3UJOmz6A1-jLgkMBEtv8NTqRKgVTgoP_ArdJT5e5kx9lX53ecjbzZ3iu3-eoV4-Qq_g$> > > I am building DMPlex using the DMPlexBuildFromCellList function and using > the exact ordering of nodes I get from the Tetgen mesh files (.ele file). > The resulting mesh looks good when I export it to VTK, but I encounter > issues when solving particular PDEs. (I can solve them while using other > importers I write) I suspect there may be orientation errors or something > similar. > > So, my question is, Is the ordering of nodes in elements important for > tetrahedral elements while using DMPlexBuildFromCellList? If so, how should > I arrange them? > Yes, TetGen inverts tetrahedra compared to Plex, since I use all outward facing normals, whereas those in TetGen are not consistently ordered. However, why not just use DMPlexGenerate() with TetGen? Thanks, Matt > Thanks, > Onur > > Sent with Proton Mail secure email. > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://urldefense.us/v3/__https://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!fZrK2yb2VL8fOhEwFSop4QgqPuB1M2_C1OMkfebpI6V32422apR69VnseJBVL8CTE5Gn4r6jRSz7K3D5kEEE$ <https://urldefense.us/v3/__http://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!fZrK2yb2VL8fOhEwFSop4QgqPuB1M2_C1OMkfebpI6V32422apR69VnseJBVL8CTE5Gn4r6jRSz7K8DmkxpU$ >
