Please help me with this problem, it happen sometimes when I use the NURBS. In this case, I use the Round tool to round the corner of the NURBS cube. However, the corner is black, so I use the reverse tool but the result is this.
Im gonna just throw a guess out there: Are you sure the problem is not with the rounding tool? When you round the edge, does it actually bend the edge and when you reverse it could it be messing the linear shape of it? I'm using just the move, rotate and scale with my isoparms, haven't yet tried that...
thank for your guess, but I already found out the problems. At first, I thought it was a bug of Maya 2015 so I delete and change to Maya 2014 again. However, it was not the bug of the 2015 version, it was actually the face was not reversed, but Maya create another face with the opposite facing direction on top of the face I chose to reverse. So I have to delete one face and then everything is ok.