Implicit function F(x,y,z）=0 F(x,y,z)<0 F(x,y,z)>0 Singed distance field is also an implicit function.𝐹 𝑥, 𝑦, 𝑧 > 0 𝐹 𝑥, 𝑦, 𝑧 = 0 𝐹 𝑥, 𝑦, 𝑧 < 0