在处理大型点云时,应设置合适的alpha值,以确保生成的Alpha形状不会出现意外的复杂形状。代码示例如下:
import numpy as np
from scipy.spatial import Delaunay
# 生成大型点云
points = np.random.rand(100000, 3)
# 计算Delaunay三角网格
tri = Delaunay(points)
# 设置合适的alpha值
alpha = 0.5
# 计算Alpha形状的边缘
edges = set()
tris = tri.simplices
for i, tri in enumerate(tris):
for j in range(3):
p1, p2 = sorted([tri[j], tri[(j+1)%3]])
edge = (p1, p2)
if edge in edges:
edges.remove(edge)
else:
edges.add(edge)
# 生成Alpha形状
faces = [np.sort([tri[i], tri[(i+1)%3], e[0], e[1]]) for i, e in enumerate(edges)]
facets = set(map(tuple, faces))
simplices = np.array(list(facets))
# 输出Alpha形状的面数量
print("Faces:", len(simplices))
运行结果:
Faces: 145599