When a texture is applied to a cylinder, it is applied differently to the sides, top, and bottom. |
On the sides, the texture wraps counterclockwise (from above) starting at the back of the cylinder. |
The texture has a vertical seam at the back, intersecting the yz-plane. |
For the top and bottom, a circle is cut out of the texture square and applied to the top or bottom circle. |
The top texture appears right side up when the top of the cylinder is tilted toward the +Z axis, and the bottom texture appears right side up when the top of the cylinder is tilted toward the -Z axis. |