In your styles, create a copy of the color you are using called something like "xxxx-90", and rotate the bitmap 90 degrees.
Then select the faces and apply a color override using the 90 degree style.
Any reason you have suggested a new material style as opposed to face specific appearance adjustments?
(Oh, you still have Inventor 2012...)
In 2013 (and newer I'm guessing) There is the 'Adjust' tool, located to the right of the 'Appearances' dropdown menu.
it can simply rotate the appearance on a per face basis, (can also change scale and tint)
Yeah 2012 doesn't have the adjusting capabilities that are in the newer versions.
I've done quite a bit of woodworking in Inventor and have typically made three color styles for each type of wood we use.
Normal, Rotated and End Grain
End Grain obviously uses a different bitmap image.
We've had some pretty good results with them using Studio.
I'll see if I can dig up some of the renders we've done and post a couple.
I installed Inventor 2014 this morning but still can't solve the problem.
I problem appears with the rounded parts. They aren't a whole piece. It's made from small squares (not me the program made them like this) and each one of them has own texture (by default) I tried to adjust the size of the texture, but ..the result wasn't good at all.