def __init__(self, vertices, center=None):
Surface.__init__(self)
c = center or _center_of_point_cloud(vertices)
self.center = c
num_vertices = len(vertices)
if len(vertices) < 2:
raise Exception('insufficient vertices')
normal = self._compute_normal(c, vertices)
v1 = vertices[0]
i = Vector(v1.x - c.x, v1.y - c.y, v1.z - c.z)
j = i.cross(normal)
vertices = vertices[:]
vertices.append(vertices[0])
s = Surface()
for index in xrange(num_vertices):
a = vertices[index]
b = vertices[index+1]
a1 = Vector(a.x - c.x, a.y - c.y, a.z - c.z)
a.tcoord = (a1.dot(i), a1.dot(j))
face = Face(Edge(c, a), Edge(a, b), Edge(b, c))
s.add(face)
self.add(s)
def mesh(self):
vertices = self.vertices
_vertices = tuple([v._obj for v in vertices])
indices = self._obj.face_indices(_vertices)
tcoords = [self.tcoords.get(v.id) for v in vertices]
no_normal_verts = [v for v in vertices if v.id not in self.vnormals]
_vnormals = {}
for v in no_normal_verts:
fnormals = [f.normal() for f in v._obj.faces()]
fnormals = [Vector(*fn).normalize() for fn in fnormals]
vnormal = Vector()
for fn in fnormals:
vnormal = vnormal + fn
vnormal = vnormal.normalize()
vnormal = (vnormal.x, vnormal.y, vnormal.z)
_vnormals[v.id] = vnormal
normals = []
for index, v in enumerate(vertices):
n = self.vnormals.get(v.id) or _vnormals[v.id]
normals.append(n)
vertices[index] = v.position
return vertices, indices, normals, tcoords
def _compute_normal(self, center, vertices):
normals = []
c = center
v1 = vertices[0]
v1 = Vector(v1.x - c.x, v1.y - c.y, v1.z - c.z)
for v in vertices[1:2]:
v = Vector(v.x - c.x, v.y - c.y, v.z - c.z)
n = v1.cross(v)
normals.append(n.normalize())
normal = Vector()
for _n in normals:
normal = normal + _n
return normal.normalize()
