hi i'm a complete newbie in computergraphics so sorry if it's a stupid answer. i'm trying to make a simple 3d engine from scratch, more for educational purpose than for real use.

i have a Surface object with inside a Triangle's list. For now i compute normals inside Triangle class, in this way:

triangle.computeFaceNormals() {
    Vec3D u = v1.sub(v3)
    Vec3D v = v1.sub(v2)
    Vec3D normal = Vec3D.cross(u,v)
    normal.normalized()
    this.n1 = this.n2 = this.n3 = normal
}

and when building surface:

t = new Triangle(v1,v2,v3).computeFaceNormals()
surface.addTriangle(t)

and i think this is the best way to do that.. isn't it?

now.. what about for vertex normals? i've found this simple algorithm: flipcode vertex normal

but.. hei this algorithm has.. exponential complexity? (if my memory doesn't fail my computer science background..) (bytheway.. it has 3 nested loops.. i don't think it's the best way to do it..)

any suggestion?