pub fn triangle_area( a: Matrix<f32, Const<3>, Const<1>, ArrayStorage<f32, 3, 1>>, b: Matrix<f32, Const<3>, Const<1>, ArrayStorage<f32, 3, 1>>, c: Matrix<f32, Const<3>, Const<1>, ArrayStorage<f32, 3, 1>>, ) -> f32