Edit: Second attempted explanation deleted. It made no sense, although I had the right basic idea.
Okay, this time for sure! Look at the last two Data statements:
Data 5,1,7,5,1,6,5,0,6
Data 5,0,7,5,1,7,5,0,6
All X values are the same. This makes all U values the same. Both triangles are textured with a single vertical stripe from the image.
Okay, this time for sure! Look at the last two Data statements:
Data 5,1,7,5,1,6,5,0,6
Data 5,0,7,5,1,7,5,0,6
All X values are the same. This makes all U values the same. Both triangles are textured with a single vertical stripe from the image.