This app uses a unique algorithm that extracts data from the selected tin surface and performs trigonometry calculations to draw a 3D polyline along the tin surface at the desired grade/slope.
3D Polyline vertices are computed at the triangle edges resulting in vertices that match the surface data. Converting the 3D polyline to a feature line results in grades that accurately represent the input grade/slope.
YouTube Presentation: https://www.youtube.com/watch?v=t6VAKWSD-7o&feature=youtu.be
Software EULA: http://www.redtransitconsultants.com/software-eula