Rotate around the X- or Y-axis.
1) Place the cursor over the structure.
2) Press and hold the left mouse button down and hold.
3) Move the mouse pointer down for +X-axis rotation.
4) Move the mouse pointer up for -X-axis rotation.
5) Move the mouse pointer right for +Y-axis rotation.
6) Move the mouse pointer left for -Y-axis rotation.
You must hold the left mouse button down while you rotate the image.