What Is the Slope of this Pitch?

The FIFA Quality Concept (2012) requires a slope lower than 1% for soccer fields (<0.5% recommended). On the other hand, the use of a single constraint is not sufficient to capture the singularities and local anomalies of the pitch. This paper presents a procedure able to (1) reconstruct the entire pitch surface and (2) analyze its shape. The method can be intended as a multi-step methodology where three-dimensional coordinates are captured with accurate and rapid surveying techniques, a model of the pitch is extracted with automated techniques for data interpolation based on non-uniform rational B-spline curves and surfaces, and raster algebra provides a detailed and exhaustive visualization of slope distribution and profile curvature.