SplineMeshComponent's collision will start to distort the longer the Spline becomes

SplineMeshComponent's collision will start to distort the longer the Spline becomes

This is a regession. It was working in 4.13.2-3172292

User Description:

When drawing out a long spline mesh ( railway track) after a certain distance the collision mesh becomes corrupted.

This has been repeated in multiple vanilla projects, using entirely different BP's

The collision mesh seems to lose a vertex after a set distance from the origin.

(in my cases it seems to be around 360 m ).

The distance seems to be affected by the cross sectional area to length of segmant.

(it does not appear to be affected by just the length of each segmant).

It affects both Custom UCX collision and collision made by adding boxes in the UE4 SM editor.

I have checked everything I can find regarding LOD

(all SM's have base LOD only)

Make a spline with cube as mesh, drag out a long spline check collision ..... as mentioned mine happens around 360 m

1. Open the attached test project
2. Look at the box collision at the start of the SplineMesh
3. Fly to the end of the SplineMesh and examine the box collision there

Results: The SplineMeshComponent's collision will start to distort the longer the Spline becomes

Expected: For the collision to maintain shape regardless of how long the SplineMesh is