[VRaySDK] Identify VRay fur strand during shading

V-Ray for 3ds Max V-Ray for 3ds Max :: Issues
1

Hi,
I have modified vrayfur sample that comes with vray. I want to randomize color of every hair strand. I know I can do that inside VRayFurInstance::shade. This is what I do:

VRenderInstance::fullShade((VRayInterface&)vri);
RayResult rresult = vri.rayresult;
GenericPrimitive *pp = rresult.primitive;	

if (pp->type() == PRIM_TYPE_STATIC_HAIR_SEGMENT_LINE)
{
StaticHairStrand *hStrand = (StaticHairStrand*)pp->owner;
int oi = pp->owner->ownerIndex;
::Random r;
float v;
r.srand(oi);
r.rand();
//now I modify vri.mtlresult.color
}

Problem is oi changes from frame to frame for same strands. Inside genStrand every strand is identified by faceIndex and strandIndex but I have no idea how can I access these data from VRayFurInstance::shade. Any idea how can I do this? Maybe I should try some different approach?