ygTransform transform1(position(-2,4,5))
    {
    ygScene scene1(file(velocity.yg),
			object1.file(sphere.pfb),
			mathematics1.when(changed,masterVelocity.set($value)))
    }
ygTransform transform2(position(2,4,5))
    {
    ygScene scene2(file(velocity.yg),
			object1.file(block1.pfb),
			wandTrigger1.volume(sphere),
			mathematics1.when(changed,masterVelocity.set($value)))
    }
value masterVelocity(when(changed,print(master velocity is: $value)))
light(direction(1 -1 1))