I came back here after 2 year without authoring, so, I may not be the best one to answer.
But I guess it's to make the use off the transformation matrix easier.
I think the point is to use the number 1 for each vertex coordinate to multiply easily.
But I guess it's to make the use off the transformation matrix easier.
I think the point is to use the number 1 for each vertex coordinate to multiply easily.