def calc_vert_tangents(self):
"""self.loop_tris.bmのBORDERフラグが立っている頂点のtangentを計算。
:return: キーがBMVert, 値が[tangent, tangent(min), tangent(max)]の
辞書を返す。tangentはself.align_edgesが偽の場合に、tangent(min)と
tangent(max)はself.align_edgesが真の場合に利用する。
fallbackはVector((0, 0, 0))とする。
:rtype: dict[BMVert, list[Vector]]
"""
WIRE = self.WIRE
BORDER = self.BORDER
loop_tris = self.loop_tris
vert_dict = loop_tris.vert_dict()
vert_tangents = {} # eve: Vector
for eve in loop_tris.bm.verts:
if not loop_tris.vflags[eve] & BORDER:
continue
# eveに接続する二頂点(vert_next, vert_prev)を求める
eve_next, eve_prev = [eed.other_vert(eve) for eed in eve.link_edges if loop_tris.eflags[eed] & BORDER]
# tangent (used when self.align_edges is False)
tris = []
for tri in vert_dict[eve]:
efa = tri[0].face
if not efa.hide:
# if not self.use_outside_calculation and efa.select or \
# self.use_outside_calculation and not efa.select:
# tris.append(tri)
if (
self.tangent_calculation in ("selected", "individual")
and efa.select
or self.tangent_calculation == "deselected"
and not efa.select
):
tris.append(tri)
tangent = LoopTris.vert_tangent(eve, eve_prev, eve_next, tris, fallback=Vector((0, 0, 0)))
# tangent_min, tangent_max (used when self.align_edges is True)
edges = []
for eed in eve.link_edges:
if eed.hide or loop_tris.eflags[eed] & (WIRE | BORDER):
continue
# if not self.use_outside_calculation and eed.select or \
# self.use_outside_calculation and not eed.select:
# edges.append(eed)
if (
self.tangent_calculation in ("selected", "individual")
and eed.select
or self.tangent_calculation == "deselected"
and not eed.select
):
edges.append(eed)
tangent_min_max = []
if len(edges) == 1:
eed = edges[0]
vec = eed.other_vert(eve).co - eve.co
if vec.length > 0:
vec.normalize()
vec1 = eve_prev.co - eve.co
if vec1.length > 0:
vec1.normalize()
f1 = vec1.cross(vec).length
if f1 > EPS:
tangent_min_max.append(vec / f1)
vec2 = eve_next.co - eve.co
if vec2.length > 0:
vec2.normalize()
f2 = vec2.cross(vec).length
if f2 > EPS:
tangent_min_max.append(vec / f2)
tangent_min_max.sort(key=lambda v: v.length)
if len(tangent_min_max) == 0:
tangents = [tangent] * 3
elif len(tangent_min_max) == 1:
tangents = [tangent] + tangent_min_max * 2
else:
tangents = [tangent] + tangent_min_max
vert_tangents[eve] = tangents
return vert_tangents
