Second-order curvature-based indices (calculation described in detail in Martufi et al.⁹)

Nomenclature	Name	Equation
GAA	Area averaged Gaussian curvature	$\mathit{\text{GAA}}=\frac{{\displaystyle {\sum }_{\mathit{\text{all elements}}}{K}_j{S}_j}}{{\displaystyle {\sum }_{\mathit{\text{all elements}}}{S}_j}}$
MAA	Area averaged Mean curvature	$\mathit{\text{MAA}}=\frac{{\displaystyle {\sum }_{\mathit{\text{all elements}}}{M}_j{S}_j}}{{\displaystyle {\sum }_{\mathit{\text{all elements}}}{S}_j}}$
GLN	L2 norm of the Gaussian curvature	$\mathit{\text{GLN}}=\frac{1}{4\pi }\sqrt{{\displaystyle {\sum }_{\mathit{\text{all elements}}}{S}_j}·{\displaystyle {\sum }_{\mathit{\text{all elements}}}\left(K_j^2{S}_j\right)}}$
MLN	L2 norm of the Mean curvature	$\mathit{\text{MLN}}=\frac{1}{4\pi }\sqrt{{\displaystyle {\sum }_{\mathit{\text{all elements}}}\left(M_j^2{S}_j\right)}}$