# RegionResize works improperly with different digital accuracy

The data is copied from the output cell of my original data.

pts={{25.3232,93.3884,7.90173},{25.3232,93.3884,15.6372},{25.3232,101.869,15.6372},{25.3232,101.869,7.90173},{25.6231,93.3884,7.90173},{25.6231,101.869,7.90173},{25.6231,93.3884,15.6372},{25.6231,101.869,15.6372},{25.6231,111.391,15.6372},{25.6231,111.391,7.90173},{25.923,101.869,7.90173},{25.923,111.391,7.90173},{25.923,101.869,15.6372},{25.923,111.391,15.6372}};

meshTest=ConvexHullMesh@pts

RegionResize[meshTest,10]


works properly

But in my original raw mesh, it works improperly.

ptsOrignal={{25.323178174128376,93.38837529045934,7.90172510421934},{25.323178174128376,93.38837330947786,15.637175854060626},{25.323178174128376,101.86875495322009,15.637176769628931},{25.323178174128376,101.86875627387441,7.901726019787645},{25.623105100248882,93.38837529045934,7.90172510421934},{25.623105100248882,101.86875627387441,7.901726019787645},{25.623105100248882,93.38837330947786,15.637175854060626},{25.623105100248882,101.86875495322009,15.637176769628931},{25.623105100248882,111.39085617922113,15.637177685197237},{25.623105100248882,111.39085882052977,7.901727850924257},{25.923034314647705,101.86875627387441,7.901726019787645},{25.923034314647705,111.39085882052977,7.901727850924257},{25.923034314647705,101.86875495322009,15.637176769628931},{25.923034314647705,111.39085617922113,15.637177685197237}};

meshTest=ConvexHullMesh@ptsOrignal

RegionResize[meshTest,10]


So is it a bug?

=== Since RegionResize is probably implemented by TransformedRegion.

This problem also happen in TransformedRegion.

TransformedRegion[meshTest,ScalingTransform[{0.01,2,0.9}]] Works Fine

TransformedRegion[meshTest,ScalingTransform[{0.01,2,0.8}]]

• Strange. Remove this point and the error goes away: {25.623105100248882, 101.86875495322009, 15.637176769628931} Jun 11 '20 at 11:53

Using FindMeshDefects shows that the second example produces "tiny faces". You can use RepairMesh as clean up step to remove such errors like so:
meshTest = ConvexHullMesh@ptsOrignal

• @HyperGroups They both worked on my machine 12.1.1 for Microsoft Windows (64-bit) (June 19, 2020)` after I repaired the mesh. If you want more options to repair the mesh, have you looked at MeshLab? I posted an answer 214907 on how to decimate a mesh from Mathematica calling MeshLab. Jul 10 '20 at 16:09