[Python知识库]#python+open3d 3D模型的读取与应用

下载open3d：
pip install open3d(0.13.0版本）
pip install open3d-python(0.7.0版本 速度较快)

参考文档
open3d官方文档
官方github
斯坦福3d图形库

读取3D文件

【点云形式】

import open3d as o3d
import numpy as np

pcd=o3d.io.read_point_cloud(r"data\bunny10k.ply")
o3d.visualization.draw_geometries([pcd],width=800,height=600)

#按ctrl±号可以减少点云的体素尺寸，ctrl++放大
#按ctrl+W会出现网格
#ctrl+p记录截图和json

【读取呈现一般格式】

mesh.compute_vertex_normals()
o3d.visualization.draw_geometries([mesh])

【调整表面碎片结构的显示】

tetra_mesh, pt_map = o3d.geometry.TetraMesh.create_from_point_cloud(pcd)
for alpha in np.logspace(np.log10(0.5), np.log10(0.01), num=4):
    print(f"alpha={alpha:.3f}")
    mesh = o3d.geometry.TriangleMesh.create_from_point_cloud_alpha_shape(
        pcd, alpha, tetra_mesh, pt_map)
    mesh.compute_vertex_normals()
    o3d.visualization.draw_geometries([mesh], mesh_show_back_face=True)

alpha=0.010时

【表面点点】

radii = [0.005, 0.01, 0.02, 0.04]
rec_mesh = o3d.geometry.TriangleMesh.create_from_point_cloud_ball_pivoting(
    pcd, o3d.utility.DoubleVector(radii))
o3d.visualization.draw_geometries([pcd, rec_mesh])

【密度可视化】

print('visualize densities')
densities = np.asarray(densities)
density_colors = plt.get_cmap('plasma')(
    (densities - densities.min()) / (densities.max() - densities.min()))
density_colors = density_colors[:, :3]
density_mesh = o3d.geometry.TriangleMesh()
density_mesh.vertices = mesh.vertices
density_mesh.triangles = mesh.triangles
density_mesh.triangle_normals = mesh.triangle_normals
density_mesh.vertex_colors = o3d.utility.Vector3dVector(density_colors)
o3d.visualization.draw_geometries([density_mesh],
                                  zoom=0.664,
                                  front=[-0.4761, -0.4698, -0.7434],
                                  lookat=[1.8900, 3.2596, 0.9284],
                                  up=[0.2304, -0.8825, 0.4101])

【显示法线】

gt_mesh = o3dtut.get_bunny_mesh()
pcd = gt_mesh.sample_points_poisson_disk(5000)
pcd.normals = o3d.utility.Vector3dVector(np.zeros(
    (1, 3)))  # invalidate existing normals

pcd.estimate_normals()
o3d.visualization.draw_geometries([pcd], point_show_normal=True)

pcd.orient_normals_consistent_tangent_plane(100)
o3d.visualization.draw_geometries([pcd], point_show_normal=True)