1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
#include "output_helper.h"
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Surface_mesh.h>
#include <CGAL/alpha_wrap_3.h>
#include <CGAL/Polygon_mesh_processing/bbox.h>
#include <CGAL/Polygon_mesh_processing/IO/polygon_mesh_io.h>
#include <iostream>
#include <string>
namespace PMP = CGAL::Polygon_mesh_processing;
using K = CGAL::Exact_predicates_inexact_constructions_kernel;
using Point_3 = K::Point_3;
using Mesh = CGAL::Surface_mesh<Point_3>;
int main(int argc, char** argv)
{
// Read the input
const std::string filename = (argc > 1) ? argv[1] : CGAL::data_file_path("meshes/armadillo.off");
std::cout << "Reading " << filename << "..." << std::endl;
Mesh input;
if(!PMP::IO::read_polygon_mesh(filename, input) ||
is_empty(input) || !is_triangle_mesh(input))
{
std::cerr << "Invalid input:" << filename << std::endl;
return EXIT_FAILURE;
}
std::cout << "Input: " << num_vertices(input) << " vertices, " << num_faces(input) << " faces" << std::endl;
const double relative_alpha = (argc > 2) ? std::stod(argv[2]) : 40.;
const double relative_offset = (argc > 3) ? std::stod(argv[3]) : 600.;
// Compute the alpha and offset values
CGAL::Bbox_3 bbox = CGAL::Polygon_mesh_processing::bbox(input);
const double diag_length = std::sqrt(CGAL::square(bbox.xmax() - bbox.xmin()) +
CGAL::square(bbox.ymax() - bbox.ymin()) +
CGAL::square(bbox.zmax() - bbox.zmin()));
const double alpha = diag_length / relative_alpha;
const double offset = diag_length / relative_offset;
// Construct the wrap
CGAL::Real_timer t;
t.start();
// There is no limit on how many seeds can be used.
// However, the algorithm automatically determines whether a seed can be used
// to initialize the refinement based on a few conditions (distance to the offset, value of alpha, etc.)
// See internal function Alpha_wrap_3::initialize_from_cavities() for more information
std::vector<Point_3> seeds =
{
Point_3(0, 50, 0) // a point within the armadillo surface
};
Mesh wrap;
alpha_wrap_3(input, alpha, offset, wrap, CGAL::parameters::seed_points(std::ref(seeds)));
t.stop();
std::cout << "Result: " << num_vertices(wrap) << " vertices, " << num_faces(wrap) << " faces" << std::endl;
std::cout << "Took " << t.time() << " s." << std::endl;
// Save the result
std::string input_name = std::string(filename);
input_name = input_name.substr(input_name.find_last_of("/") + 1, input_name.length() - 1);
input_name = input_name.substr(0, input_name.find_last_of("."));
std::string output_name = input_name + "_cavity_" + std::to_string(static_cast<int>(relative_alpha))
+ "_" + std::to_string(static_cast<int>(relative_offset)) + ".off";
std::cout << "Writing to " << output_name << std::endl;
CGAL::IO::write_polygon_mesh(output_name, wrap, CGAL::parameters::stream_precision(17));
return EXIT_SUCCESS;
}
|
