int colorG = (int) tubePosition.g;
int colorB = (int) tubePosition.b;
double radius = tubePosition.radius;
points.InsertNextPoint(x, y, z);
colorArray.InsertNextTuple3(colorR, colorG, colorB);
radiusArray.InsertNextValue(radius);
}
// add the lastube
if (points != null) {