Unity provides standard spline asset,
use BGCurve only if Unity spline misses some feature

Triangulates 2D spline. Simple polygons only (no intersections). UVs are also generated, based on min/max point positions (imagine a bounding square with lower left point [0,0] and upper right point [1.1] being projected on spline's plane)

splitMode

The mode for splitting a spline. 1) PartsTotal - use specified number parts for whole spline. 2) PartsPerSection - use specified number parts for each section (between 2 points) 3) UseMathData -use data, precalculated by Math component. Note, you can tweak some params at Math as well

partsTotal

The number of splits for TotalSections mode. The actual number of parts can be less than partsTotal due to optimization, but never more.

partsPerSection

The number of splits for PartSections mode. The actual number of parts can be less than partsPerSection due to optimization, but never more.

doNotOptimizeStraightLines

Split straight lines. Straight lines are optimized by default and are not split, but you can override it with this parameter.

updateEveryFrame

Update mesh every frame even if spline is not changed. This could be useful if UVs are animated.

flip

Flips faces (normals)

scaleUV

Scale UV coordinates

offsetUV

Offset UV coordinates

doubleSided

Generate mesh for backside. This will double the amount of vertices and triangles.

scaleBackUV

Scale back UV coordinates

offsetBackUV

Offset back UV coordinates

showHandles

This component supports handles in Scene View. Enable this flag to show handles. Handles are not interactive.

spheresScale

Adjust spheres scale. Each sphere represent one point of the generated mesh.

spheresColor

Set spheres color.

spheresCount

The number of first N points (spheres) to show. The number is restricted for performance reason.