Straight board: suitable for single-slope, double-slope and single-curved roofs with a radius larger than the natural arc radius;
Positive and negative arc panels: suitable for single-curved roofs with a radius smaller than the natural arc radius;
Fan panels and fan arc panels: suitable for hyperbolic roofs;
Special case: straight board is used on hyperboloid, the roof curvature is small, and multiple ridges are allowed on the roof.
