Generates a single-wall instanced-tube description for a wellbore trajectory.
Unlike generateTubeTrajectory, radius is NOT baked into the geometry —
this returns per-segment centerline data (position, tangent, stable frame normal,
curve position) that the trajectory shader displaces into a tube using a radius
uniform. It mirrors the casing generator, minus the inner wall / radius steps.
Generates a single-wall instanced-tube description for a wellbore trajectory.
Unlike generateTubeTrajectory, radius is NOT baked into the geometry — this returns per-segment centerline data (position, tangent, stable frame normal, curve position) that the trajectory shader displaces into a tube using a radius uniform. It mirrors the casing generator, minus the inner wall / radius steps.