Freeze and explosive memory growth when newing a ConvexHull with specific input

[Eideren]

Hey there, pretty much as the title says. Program blocks somewhere in this function/loop https://github.com/bepu/bepuphysics2/blob/master/BepuPhysics/Collidables/ConvexHullHelper.cs#L868 it eats up more than a gig per second, saturating my ram and freezing the operating system.

We're on 2.5.0-beta.19, haven't had time to test on a more recent version, let me know.

This is the repro, it's kind of large for a convex but testing other similar convexes did not result in this issue.

var points = new System.Numerics.Vector3[]
{
     new(-0.637357891f, 0.347849399f, -0.303436399f),
     new(-0.636290252f, 0.345867455f, -0.301366687f),
     new(-0.992014945f, 0.348357588f, -0.3031407f),
     new(-1.00909662f, 0.386065364f, -0.303337872f),
     new(0.637357891f, 0.347849399f, -0.303436399f),
     new(-0.636290252f, 0.345918268f, 0.701366544f),
     new(-0.636503756f, 0.345918268f, 0.700873733f),
     new(-0.992655516f, 0.346578926f, 0.701070845f),
     new(-0.992655516f, 0.346578926f, -0.301070988f),
     new(0.636290252f, 0.345867455f, -0.301366687f),
     new(-0.995858312f, 0.348510057f, -0.301859498f),
     new(-1.01272643f, 0.385912925f, -0.302056611f),
     new(-1.01037765f, 0.390029252f, -0.302746475f),
     new(-0.637357891f, 0.389521062f, -0.302845061f),
     new(1.00909662f, 0.386065364f, -0.303337872f),
     new(0.992014945f, 0.348357588f, -0.3031407f),
     new(-0.637357891f, 0.347849399f, 0.703436255f),
     new(-0.992014945f, 0.348357588f, 0.703140557f),
     new(0.636290252f, 0.345918268f, 0.701366544f),
     new(-0.995858312f, 0.348510057f, 0.701859355f),
     new(-1.02553761f, 0.351406753f, 0.678599536f),
     new(-1.0251106f, 0.35013628f, 0.675938487f),
     new(-1.0251106f, 0.35013628f, -0.2759386f),
     new(-1.02553761f, 0.351406753f, -0.278599679f),
     new(0.992655516f, 0.346578926f, -0.301070988f),
     new(0.992655516f, 0.346578926f, 0.701070845f),
     new(0.636503756f, 0.345918268f, 0.700873733f),
     new(-1.04432738f, 0.37869662f, -0.274558783f),
     new(-1.01400757f, 0.389673531f, -0.301465213f),
     new(-1.04582202f, 0.382304758f, -0.273770332f),
     new(-1.0582062f, 0.67344743f, -0.220745891f),
     new(-1.0545764f, 0.674260557f, -0.22183004f),
     new(-0.637144327f, 0.674158931f, -0.221928596f),
     new(1.01037765f, 0.390029252f, -0.302746475f),
     new(0.637357891f, 0.389521062f, -0.302845061f),
     new(1.01272643f, 0.385912925f, -0.302056611f),
     new(0.995858312f, 0.348510057f, -0.301859498f),
     new(-1.00909662f, 0.386065364f, 0.703337729f),
     new(0.637357891f, 0.347849399f, 0.703436255f),
     new(0.992014945f, 0.348357588f, 0.703140557f),
     new(-1.01272643f, 0.385912925f, 0.702056468f),
     new(-1.04432738f, 0.37869662f, 0.67455864f),
     new(-1.04582202f, 0.380170345f, 0.671404779f),
     new(-1.04582202f, 0.380170345f, -0.271404922f),
     new(1.02553761f, 0.351406753f, -0.278599679f),
     new(1.0251106f, 0.35013628f, -0.2759386f),
     new(1.0251106f, 0.35013628f, 0.675938487f),
     new(1.02553761f, 0.351406753f, 0.678599536f),
     new(0.995858312f, 0.348510057f, 0.701859355f),
     new(-1.08980727f, 0.656575501f, -0.196303427f),
     new(-1.09023428f, 0.656982064f, -0.193346679f),
     new(-1.0584197f, 0.67675066f, -0.21867618f),
     new(-1.0550034f, 0.677512944f, -0.219858885f),
     new(-1.09023428f, 0.659827888f, -0.194233686f),
     new(0.637144327f, 0.674158931f, -0.221928596f),
     new(1.01400757f, 0.389673531f, -0.301465213f),
     new(1.0545764f, 0.674260557f, -0.22183004f),
     new(1.0582062f, 0.67344743f, -0.220745891f),
     new(1.04582202f, 0.382304758f, -0.273770332f),
     new(1.04432738f, 0.37869662f, -0.274558783f),
     new(-0.637357891f, 0.389521062f, 0.702844918f),
     new(-1.01037765f, 0.390029252f, 0.702746332f),
     new(1.00909662f, 0.386065364f, 0.703337729f),
     new(-1.01400757f, 0.389673531f, 0.70146507f),
     new(-1.04582202f, 0.382304758f, 0.673770189f),
     new(-1.09023428f, 0.656982064f, 0.593346536f),
     new(1.04582202f, 0.380170345f, -0.271404922f),
     new(1.04582202f, 0.380170345f, 0.671404779f),
     new(1.04432738f, 0.37869662f, 0.67455864f),
     new(1.01272643f, 0.385912925f, 0.702056468f),
     new(-1.09066129f, 0.832155526f, 0.199999928f),
     new(-1.0584197f, 0.86234206f, -0.0161386579f),
     new(-1.0550034f, 0.863663316f, -0.0167300105f),
     new(1.0550034f, 0.677512944f, -0.219858885f),
     new(-1.09023428f, 0.833781719f, -0.00135488808f),
     new(1.08980727f, 0.656575501f, -0.196303427f),
     new(1.0584197f, 0.67675066f, -0.21867618f),
     new(1.09023428f, 0.659827888f, -0.194233686f),
     new(1.09023428f, 0.656982064f, -0.193346679f),
     new(0.637357891f, 0.389521062f, 0.702844918f),
     new(1.01037765f, 0.390029252f, 0.702746332f),
     new(-0.637144327f, 0.674158931f, 0.621928453f),
     new(-1.0545764f, 0.674260557f, 0.621829867f),
     new(-1.0582062f, 0.67344743f, 0.620745778f),
     new(-1.08980727f, 0.656575501f, 0.596303284f),
     new(-1.09023428f, 0.659827888f, 0.594233513f),
     new(1.04582202f, 0.382304758f, 0.673770189f),
     new(1.09023428f, 0.656982064f, 0.593346536f),
     new(1.01400757f, 0.389673531f, 0.70146507f),
     new(-1.09044778f, 0.834950566f, 0.199999928f),
     new(-1.09023428f, 0.833781719f, 0.40135473f),
     new(-1.0584197f, 0.863663316f, -0.0124919862f),
     new(-1.0550034f, 0.865035474f, -0.0132804662f),
     new(1.0550034f, 0.863663316f, -0.0167300105f),
     new(-1.09002078f, 0.835204661f, 0.00219321251f),
     new(1.0584197f, 0.86234206f, -0.0161386579f),
     new(1.09023428f, 0.833781719f, -0.00135488808f),
     new(1.09066129f, 0.832155526f, 0.199999928f),
     new(1.0582062f, 0.67344743f, 0.620745778f),
     new(1.0545764f, 0.674260557f, 0.621829867f),
     new(0.637144327f, 0.674158931f, 0.621928453f),
     new(-1.0550034f, 0.677512944f, 0.619858742f),
     new(-1.0584197f, 0.67675066f, 0.618676066f),
     new(-1.0584197f, 0.86234206f, 0.41613853f),
     new(1.08980727f, 0.656575501f, 0.596303284f),
     new(1.09023428f, 0.659827888f, 0.594233513f),
     new(-1.09002078f, 0.835204661f, 0.397806644f),
     new(-1.05863321f, 0.863612533f, 0.199999928f),
     new(-1.0584197f, 0.863663316f, 0.412491858f),
     new(-1.0550034f, 0.865035474f, 0.413280308f),
     new(1.0550034f, 0.865035474f, -0.0132804662f),
     new(1.0584197f, 0.863663316f, -0.0124919862f),
     new(1.09002078f, 0.835204661f, 0.00219321251f),
     new(1.09044778f, 0.834950566f, 0.199999928f),
     new(1.09023428f, 0.833781719f, 0.40135473f),
     new(1.0584197f, 0.67675066f, 0.618676066f),
     new(1.0550034f, 0.677512944f, 0.619858742f),
     new(-1.0550034f, 0.863663316f, 0.416729867f),
     new(1.0584197f, 0.86234206f, 0.41613853f),
     new(1.0550034f, 0.865035474f, 0.413280308f),
     new(1.05863321f, 0.863612533f, 0.199999928f),
     new(1.09002078f, 0.835204661f, 0.397806644f),
     new(1.0584197f, 0.863663316f, 0.412491858f),
     new(1.0550034f, 0.8636633f, 0.41672987f),
};
var convex = new ConvexHull(points, AnyOldPool, out _);

[RossNordby]

(Noting that I've seen this! Currently traveling; probably will be some days before I can actually poke this.)

[RossNordby]

Reproduced; something wonky with face merges. Still going to be a while before I have the time to actually fix it; hopefully in the next two weeks.

Thanks for the report!

[RossNordby]

(it occurs to me that the next two weeks contain two conferences and a bunch of additional travel and I should have probably said three weeks; this is going to be a very solid record for my Longest Bug Turnaround)

[Eideren]

That's okay, we're all working on open-source time here, I understand the struggle :)