PK_blend_convexity_t

typedef int PK_blend_convexity_t;

Used in:

PK_FACE_identify_blends_o_t
PK_FACE_identify_blends_r_t

This field can take one of the following values:

    PK_blend_convexity_any_c       The blend may be either convex or concave
    PK_blend_convexity_concave_c   The blend is concave
    PK_blend_convexity_convex_c    The blend is convex

A blend is classified as being concave if the normals of the faces adjacent to
the blend point in towards each other.  A blend is convex if the adjacent
faces' normals point away from each other.