face-normal ( edge -- n )

Vocabulary

euler.b-rep

Inputs

edge

an object

Outputs

n

an object

Definition

USING: game.models.half-edge kernel math math.vectors sequences
;

IN: euler.b-rep

: face-normal ( edge -- n )
    face-edges
    [ dup face-ccw dup face-ccw [ vertex-pos ] tri@ normal ] map
    [ [ zero? ] all? not ] find nip
    [ normalize ] [ all-points-colinear ] if* ;