PlaneProjection doesn't generate correctly if the camera is pointed directly upwards or downwards

[Zallist]

If the camera is pointed EXACTLY upwards or downwards, such that direction == Vector3(0,1,0) or Vector3(0,-1,0) then the projection will fail and the interpolation matrix is filled with NaN values.

This happens because of the following line of code: https://github.com/Scrawk/Brunetons-Ocean/blob/e764ccb6cf67c12bbbe40e170f7991332c981ddc/Assets/BrunetonsOcean/Scripts/Projection.cs#L353

This should become the following code:

            Vector3 zaxis = (position - target).normalized;
            Vector3 xaxis = Vector3.Cross(up, zaxis).normalized;

            if (Mathf.Approximately(xaxis.magnitude, 0f))
            {
                up = Vector3.right;
                xaxis = Vector3.Cross(up, zaxis).normalized;

                if (Mathf.Approximately(xaxis.magnitude, 0f))
                {
                    up = Vector3.forward;
                    xaxis = Vector3.Cross(up, zaxis).normalized;
                }
            }

            Vector3 yaxis = Vector3.Cross(zaxis, xaxis);

Basically, if the cross of zaxis and up is a zero vector, then pick right arbitrarily. If THAT is still somehow 0, then pick forward. The extra check to forward isn't really necessary but it's the standard pattern for LookAt.