The people on your shirt are dancing, but one half has them upside down. No, not a new fashion trend, but something that went wrong in manufacturing. This is an example of what Nap means and how it can affect the look of drapes.
Most theatrical drapery is sewn from a type of velour fabric and that velour will always have a nap, or direction. The short fibers that create the texture of the velour will look lighter or darker, depending on the direction it is seen from, or placed when sewn. It could even look like a different color altogether.
When drapery fabrics are being ordered the total amount of fabric needed is always based on the sections, (or cuts) being laid out in the same direction for every drape in the package. You don’t want the stage left drapes looking like they were made of different fabric than stage right.