FillPolygon changes in 2017r2

I just noticed that 2017r2 changed the way FillPolygon works. I had a bug in my code that didn’t show if until 2017r2.

The problem all stemmed from FillPolygon using a 1 based array. Apparently now when the points array ends at an uneven index the result is undefined.

I had been creating my points like this and didn’t append the unused 0 index at the beginning.

points.append x1 points.append y1 points.append x2 points.append y2 points.append x3 points.append y3

So why in the world does FillPolygon use a 1 based array anyway?

Don’t know; but for as long as I can recall it’s always used a 1 based array with entry 0 being ignored.

It seems to me that this is how Graphics.FillPolygon has always worked.