Non-zero coordinate index causes incorrect rendering of preview nodes in material editor

In this simple example you can see a correctly functioning preview of the result of a multiply operation. Inside the TexCoord node the Coordinate Index is set to 0:

42870-texcood_bug.jpg

However if you change the Coordinate Index to 1, the preview stops working. The realtime preview in the 3D preview works correctly, it is only the node previews that are incorrect.

42881-texcood_bug2.jpg

Am I doing something wrong or is this a bug?

Hi Pyronious -

Thank you for your report. I reproduced this internally and have entered a bug report, UE-15780 for reference. I will keep you informed as we investigate a solution to this issue, however, since the Material Preview itself does not behave differently this issue may be backlogged for quite a while.

Eric Ketchum