The documentation on the Sine node (Math Material Expressions in Unreal Engine | Unreal Engine 5.0 Documentation) sais that the input is in radians, but it seems the input is pre-multiplied by PI, so that a input of 1 is actually PI radians. Please fix documentation, or fix the Sine node to act as the documentation sais. Thanks!
I think the Sine node by accident acts the same as LinearSine function. It seems that an input of 1 represents 2*PI radians.
Most likely a bug
The sine value is normalized to be a value between 0 and 1 because the UV space is normalized to be between 0 and 1.
the documentation doesn’t match that
Thanks for pointing that out, BramV. It appears that the entire run of the Sine or Cosine function is mapped to the range [0, 1], so 1.0 would indicate 2 PI radians, or 360 degrees. The reasoning behind this is that “zero to one” mappings are very convenient since they can be used easily with things like RGBA values that already exist in that range, they turn into a “one loop per second” value if Time is used as an input with no scaling factor, and, in general, material functions are often set up to map to that range. I’m updating our documentation now with new images showing number values on both the X and Y axes, and new text to indicate the actual frequency of the function. Our site will updated on the next time we publish, which is usually about once a week.