Professor pointed out in class that this image is wrong since the rotation is 90deg clockwise rather than counter-clockwise.
But I think the picture is correct. The reason is that the rotation matrix has -sin(90) in the bottom left rather than the top right (the convention in rotation matrices). So if you plug in negative 90 degrees into the rotation matrix, you will get what they have shown.
Staffjamesfobrien
Actually, you're right! It's written like a left-handed rotation. See why I said not sticking to right-handed is bad and leads to code-bugs...
(I'll pretend I knew all along and this was always my plan.)
Professor pointed out in class that this image is wrong since the rotation is 90deg clockwise rather than counter-clockwise.
But I think the picture is correct. The reason is that the rotation matrix has -sin(90) in the bottom left rather than the top right (the convention in rotation matrices). So if you plug in negative 90 degrees into the rotation matrix, you will get what they have shown.
Actually, you're right! It's written like a left-handed rotation. See why I said not sticking to right-handed is bad and leads to code-bugs... (I'll pretend I knew all along and this was always my plan.)