i'm doing the Tutorial Shapes.and I'm working on the blue rectangle. it's a perfect angular rectangle. A white dot appears in the upper right corner. I drag it down. The rectangle 's corners get rounded.We now can see another white dot in upper right corner. I drag it to the left. Rectangle's shape changes further. I drag this same dot (on the top part of rectangle) back to the corner. And i'm surprised to see that it has become a prefect rectangle again i thought it could only be a perfect (angular) rectangle if the two white dots are in the upper-right corner. It gets even stranger. I play around with the up-and-down white dot (the dot on the right side of the rectangle). Dragging it up or down doesn't change the shape of the now not-rounded rectangle.