PrusaSlicer-NonPlainar/tests/libslic3r/test_meshboolean.cpp
2021-08-30 22:57:14 +02:00

795 lines
26 KiB
C++

#include <catch2/catch.hpp>
#include <test_utils.hpp>
#include <libslic3r/TriangleMesh.hpp>
#include <libslic3r/MeshBoolean.hpp>
#include <libslic3r/SimplifyMesh.hpp>
using namespace Slic3r;
TEST_CASE("CGAL and TriangleMesh conversions", "[MeshBoolean]") {
TriangleMesh sphere = make_sphere(1.);
auto cgalmesh_ptr = MeshBoolean::cgal::triangle_mesh_to_cgal(sphere);
REQUIRE(cgalmesh_ptr);
REQUIRE(! MeshBoolean::cgal::does_self_intersect(*cgalmesh_ptr));
TriangleMesh M = MeshBoolean::cgal::cgal_to_triangle_mesh(*cgalmesh_ptr);
REQUIRE(M.its.vertices.size() == sphere.its.vertices.size());
REQUIRE(M.its.indices.size() == sphere.its.indices.size());
REQUIRE(M.volume() == Approx(sphere.volume()));
REQUIRE(! MeshBoolean::cgal::does_self_intersect(M));
}
Vec3d calc_normal(const Vec3i &triangle, const std::vector<Vec3f> &vertices)
{
Vec3d v0 = vertices[triangle[0]].cast<double>();
Vec3d v1 = vertices[triangle[1]].cast<double>();
Vec3d v2 = vertices[triangle[2]].cast<double>();
// n = triangle normal
Vec3d n = (v1 - v0).cross(v2 - v0);
n.normalize();
return n;
}
TEST_CASE("Add TriangleMeshes", "[MeshBoolean]")
{
TriangleMesh tm1 = make_sphere(1.6, 1.6);
Vec3f move(5, -3, 7);
move.normalize();
tm1.translate(0.3 * move);
its_write_obj(tm1.its, "tm1.obj");
TriangleMesh tm2 = make_cube(1., 1., 1.);
its_write_obj(tm2.its, "tm2.obj");
MeshBoolean::cgal::plus(tm1, tm2);
its_write_obj(tm1.its, "test_add.obj");
}
#include "libslic3r/Emboss.hpp"
Polygons ttf2polygons(const char * font_name, char letter, float flatness = 1.f) {
auto font = Emboss::load_font(font_name);
if (!font.has_value()) return Polygons();
font->flatness = flatness;
return Emboss::letter2polygons(*font, letter);
}
#include "libslic3r/SVG.hpp"
void store_to_svg(Polygons polygons,std::string file_name = "letter.svg")
{
double scale = 1e6;
BoundingBox bb;
for (auto& p : polygons) {
p.scale(scale);
bb.merge(p.points);
}
SVG svg(file_name, bb);
svg.draw(polygons);
}
struct Plane
{
Vec3d point = Vec3d(0., 0., 0.); // lay on plane - define zero position
Vec3d normal = Vec3d(0., 0., 1.);// [unit vector] - define orientation
};
struct OrientedPlane: public Plane
{
// Must be perpendiculat to normal
Vec3d up = Vec3d(0., 1., 0.); // [unit vector]
};
struct EmbossConfig
{
// emboss plane must be above surface
// point define zero for 2d polygon and must be out of model
// normal is direction to model
// up define orientation of polygon
OrientedPlane projection;
// Move surface distance
// Positive value out of model (Raised)
// Negative value into model (Engraved)
float height = 1.; // [in milimeters]
};
struct FontConfig
{
const char *font_path = "C:/windows/fonts/arialbd.ttf";
float flatness = 2.; // precision of lettter outline curve in conversion to lines
float scale = 1.0; // size of text
float letter_space = 1.; // unscaled space between letters
float line_space = 1.; // unscaled space between lines
};
struct Seam
{
std::vector<size_t> seam_points; // indexes of vertices which made seam
std::vector<size_t> inner_faces; // indexes of triangle (its.indices) which are inside of polygon
std::vector<size_t> outline_faces; // indexes of triangle (its.indices) contains seam points
};
#include <optional>
#include <libslic3r/AABBTreeIndirect.hpp>
Vec3d calc_hit_point(const igl::Hit & h,
const Vec3i & triangle,
const std::vector<Vec3f> &vertices)
{
double c1 = h.u;
double c2 = h.v;
double c0 = 1.0 - c1 - c2;
Vec3d v0 = vertices[triangle[0]].cast<double>();
Vec3d v1 = vertices[triangle[1]].cast<double>();
Vec3d v2 = vertices[triangle[2]].cast<double>();
return v0 * c0 + v1 * c1 + v2 * c2;
}
Vec3d calc_hit_point(const igl::Hit &h, indexed_triangle_set &its)
{
return calc_hit_point(h, its.indices[h.id], its.vertices);
}
TEST_CASE("Test hit point", "[AABBTreeIndirect]")
{
indexed_triangle_set its;
its.vertices = {
Vec3f(1,1,1),
Vec3f(2, 10, 2),
Vec3f(10, 0, 2),
};
its.indices = {Vec3i(0, 2, 1)};
auto tree = AABBTreeIndirect::build_aabb_tree_over_indexed_triangle_set(
its.vertices, its.indices);
Vec3d ray_point(8, 1, 0);
Vec3d ray_dir(0,0,1);
igl::Hit hit;
AABBTreeIndirect::intersect_ray_first_hit(its.vertices, its.indices, tree,
ray_point, ray_dir, hit);
Vec3d hp = calc_hit_point(hit, its);
CHECK(abs(hp.x() - ray_point.x()) < .1);
CHECK(abs(hp.y() - ray_point.y()) < .1);
}
// represents triangle extend by seam
struct TrianglePath
{
// input edge, output edge, when cross triangle border
std::optional<std::pair<char, char>> edges;
// when edges has value than first and last point lay on triangle edge
std::vector<Vec3f> points;
// first point has index offset_id in result vertices
uint32_t offset_id;
};
using TrianglePaths = std::vector<TrianglePath>;
std::vector<Vec3i> triangulate(const Vec3i &triangle, const Vec3d &triangle_normal, const std::vector<Vec3f> &vertices, const TrianglePaths& paths);
// create transformation matrix to convert direction vectors
// do not care about up vector
// Directions are normalized
Eigen::Matrix3d create_transformation(const Vec3d &from_dir, const Vec3d &to_dir)
{
Vec3d axis = from_dir.cross(to_dir);
axis.normalize();
double angle = acos(from_dir.dot(to_dir));
auto rotation = Eigen::AngleAxisd(angle, axis);
return rotation.matrix();
}
TEST_CASE("Transformation matrix", "[]") {
Vec3d d1(3, -7, 13);
Vec3d d2(-9, 5, 1);
d1.normalize();
d2.normalize();
auto tr_mat = create_transformation(d1, d2);
Vec3d d1_tr = tr_mat * d1;
Vec3d diff = d1_tr - d2;
double eps = 1e-12;
for (double d : diff)
CHECK(abs(d) < std::numeric_limits<double>::epsilon());
}
// calculate multiplication of ray dir to intersect - inspired by segment_segment_intersection
// when ray dir is normalized retur distance from ray point to intersection
// No value mean no intersection
std::optional<double> ray_segment_intersection(
const Vec2d& r_point, const Vec2d& r_dir, const Vec2d& s0, const Vec2d& s1){
auto denominate = [](const Vec2d& v0,const Vec2d& v1)->double{
return v0.x() * v1.y() - v1.x() * v0.y();
};
Vec2d segment_dir = s1 - s0;
double d = denominate(segment_dir, r_dir);
if (std::abs(d) < std::numeric_limits<double>::epsilon())
// Line and ray are collinear.
return {};
Vec2d s12 = s0 - r_point;
double s_number = denominate(r_dir, s12);
bool change_sign = false;
if (d < 0.) {
change_sign = true;
d = -d;
s_number = -s_number;
}
if (s_number < 0.|| s_number > d)
// Intersection outside of segment.
return {};
double r_number = denominate(segment_dir, s12);
if (change_sign)
r_number = - r_number;
if(r_number < 0.)
// Intersection before ray start.
return {};
return r_number / d;
}
TEST_CASE("ray segment intersection", "[MeshBoolean]")
{
Vec2d r_point(1,1);
Vec2d r_dir(1,0);
// colinear
CHECK(!ray_segment_intersection(r_point, r_dir, Vec2d(0,0), Vec2d(2,0)).has_value());
CHECK(!ray_segment_intersection(r_point, r_dir, Vec2d(2,0), Vec2d(0,0)).has_value());
// before ray
CHECK(!ray_segment_intersection(r_point, r_dir, Vec2d(0,0), Vec2d(0,2)).has_value());
CHECK(!ray_segment_intersection(r_point, r_dir, Vec2d(0,2), Vec2d(0,0)).has_value());
// above ray
CHECK(!ray_segment_intersection(r_point, r_dir, Vec2d(2,2), Vec2d(2,3)).has_value());
CHECK(!ray_segment_intersection(r_point, r_dir, Vec2d(2,3), Vec2d(2,2)).has_value());
// belove ray
CHECK(!ray_segment_intersection(r_point, r_dir, Vec2d(2,0), Vec2d(2,-1)).has_value());
CHECK(!ray_segment_intersection(r_point, r_dir, Vec2d(2,-1), Vec2d(2,0)).has_value());
// intersection at [2,1] distance 1
auto t1 = ray_segment_intersection(r_point, r_dir, Vec2d(2,0), Vec2d(2,2));
REQUIRE(t1.has_value());
auto t2 = ray_segment_intersection(r_point, r_dir, Vec2d(2,2), Vec2d(2,0));
REQUIRE(t2.has_value());
CHECK(abs(*t1 - *t2) < std::numeric_limits<double>::epsilon());
}
Vec2d get_intersection(const Vec2d& point, const Vec2d& dir, const std::array<Vec2d, 3>& triangle)
{
std::optional<double> t;
for (size_t i = 0; i < 3; ++i) {
size_t i2 = i+1;
if(i2 == 3) i2 = 0;
if (!t.has_value()) {
t = ray_segment_intersection(point, dir, triangle[i], triangle[i2]);
continue;
}
// small distance could be preccission inconsistance
std::optional<double> t2 = ray_segment_intersection(
point, dir, triangle[i], triangle[i2]);
if (t2.has_value() && *t2 > *t) t = t2;
}
assert(t.has_value()); //Not found intersection.
return point + dir * (*t);
}
TEST_CASE("triangle intersection", "[]")
{
Vec2d point(1,1);
Vec2d dir(-1, 0);
std::array<Vec2d, 3> triangle = {
Vec2d(0, 0),
Vec2d(5, 0),
Vec2d(0, 5)
};
Vec2d i = get_intersection(point, dir, triangle);
CHECK(abs(i.x()) < std::numeric_limits<double>::epsilon());
CHECK(abs(i.y() - 1.) < std::numeric_limits<double>::epsilon());
}
#include <libslic3r/Geometry.hpp>
std::optional<Seam> create_seam(const Polygon &shape, const OrientedPlane& plane, indexed_triangle_set &its) {
// IMPROVE: create area of interests (mask for neighbors)
auto neighbors = its_face_edge_ids(its);
auto tree = AABBTreeIndirect::build_aabb_tree_over_indexed_triangle_set(
its.vertices, its.indices);
const Vec3d z_axis(0, 0, 1);
// IMPROVE: parallelize
// collect intersection with model
const Vec3d& ray_dir = plane.normal;
Vec3d side = plane.up.cross(plane.normal);
std::vector<igl::Hit> hits;
hits.reserve(shape.points.size());
for (const Point &p : shape.points) {
Vec3d ray_point = plane.point +plane.up*p.y()+side*p.x();
igl::Hit hit;
AABBTreeIndirect::intersect_ray_first_hit(its.vertices, its.indices,
tree, ray_point, ray_dir,
hit);
hits.push_back(hit);
}
// triangle idx, changes inside triangle
std::map<size_t, TrianglePaths> changes;
std::set<size_t> remove_indices;
std::vector<Vec3f> add_vertices;
std::vector<Vec3i> add_indices;
for (size_t i = 0; i < shape.points.size(); ++i) {
size_t next_i = i + 1;
if (i == shape.points.size()) next_i = 0;
Point dir2d = shape.points[next_i] - shape.points[i];
Vec3d dir = dir2d.x() * side + dir2d.y() * plane.up;
const igl::Hit &start_hit = hits[i];
size_t ti = start_hit.id; // triangle index
const igl::Hit &end_hit = hits[next_i];
Vec3i t = its.indices[ti];
Vec3d hit_point = calc_hit_point(start_hit, t, its.vertices);
Vec3d start_point = hit_point;
std::optional<size_t> edge_index;
while (ti != end_hit.id) {
Vec3d n = calc_normal(t, its.vertices); // triangle normal
Eigen::Matrix3d rotation = create_transformation(n, z_axis);
Vec3d t_dir = n.cross(dir).cross(n); // direction on triangle surface
auto remove_z = [&](const Vec3d &point) -> Vec2d {
Vec3d rotated_point = rotation * point;
assert(abs(rotated_point.z()) < 1e-5);
return Vec2d(rotated_point.x(), rotated_point.y());
};
std::array<Vec2d, 3> triangle2d;
for (size_t i = 0; i < 3; ++i)
triangle2d[i] = remove_z(its.vertices[t[i]].cast<double>());
Vec2d start_point_2d = remove_z(start_point);
// move start point on edge of this triangle
if (edge_index.has_value()) {
size_t e2 = *edge_index +1;
if (e2 == 3) e2 = 0;
const Vec2d &p1 = triangle2d[*edge_index];
const Vec2d &p2 = triangle2d[e2];
Vec2d dir = p2 - p1;
start_point_2d = Geometry::foot_pt(p1, dir, start_point_2d);
}
Vec2d dir_point_2d = remove_z(start_point+t_dir);
Vec2d next_point_2d = get_intersection(start_point_2d, dir_point_2d, triangle2d);
//next_triangle =
// Find interection with triangle border from start point in direction t_dir
// ?? Convert to 2d?
}
}
// connect hits over surface
return {};
}
std::vector<Vec3i> triangulate(const std::vector<Vec2f> & points,
const std::vector<std::pair<int, int>> &edges);
std::vector<Vec3i> triangulate(const Polygon &polygon) {
const Points &pts = polygon.points;
std::vector<Vec2f> points;
points.reserve(pts.size());
std::transform(pts.begin(), pts.end(), std::back_inserter(points),
[](const Point &p) -> Vec2f { return p.cast<float>(); });
std::vector<std::pair<int, int>> edges;
edges.reserve(pts.size());
for (int i = 1; i < pts.size(); ++i) edges.emplace_back(i - 1, i);
edges.emplace_back(pts.size() - 1, 0);
return triangulate(points, edges);
}
indexed_triangle_set emboss3d(const Polygon &shape, float height) {
// CW order of triangle indices
std::vector<Vec3i> shape_triangles = triangulate(shape);
indexed_triangle_set result;
const Points &pts = shape.points;
size_t count_point = pts.size();
result.vertices.reserve(2 * count_point);
// top points
std::transform(pts.begin(), pts.end(), std::back_inserter(result.vertices),
[](const Point &p) { return Vec3f(p.x(), p.y(), 0); });
// bottom points
std::transform(pts.begin(), pts.end(), std::back_inserter(result.vertices),
[height](const Point &p) { return Vec3f(p.x(), p.y(), height); });
result.indices.reserve(shape_triangles.size() * 2 + count_point*2);
// top triangles - change to CCW
for (const Vec3i &t : shape_triangles)
result.indices.emplace_back(t.x(), t.z(), t.y());
// bottom triangles - use CW
for (const Vec3i &t : shape_triangles)
result.indices.emplace_back(
t.x() + count_point,
t.y() + count_point,
t.z() + count_point
);
// quads around - zig zag by triangles
for (uint32_t i = 0; i < count_point; ++i) {
// previous index
uint32_t ip = (i == 0) ? (count_point - 1) : (i - 1);
// bottom indices
uint32_t i2 = i + count_point;
uint32_t ip2 = ip + count_point;
result.indices.emplace_back(i, i2, ip);
result.indices.emplace_back(ip2, ip, i2);
}
return result;
}
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Exact_predicates_exact_constructions_kernel.h>
#include <CGAL/Surface_mesh.h>
#include <CGAL/Polygon_mesh_processing/corefinement.h>
typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
typedef CGAL::Exact_predicates_exact_constructions_kernel EK;
typedef CGAL::Surface_mesh<K::Point_3> Mesh;
namespace PMP = CGAL::Polygon_mesh_processing;
namespace params = PMP::parameters;
// is it realy neccessary to copy all?
Mesh its_to_mesh(const indexed_triangle_set &its)
{
Mesh mesh;
size_t vertices_count = its.vertices.size();
size_t edges_count = (its.indices.size() * 3) / 2;
size_t faces_count = its.indices.size();
mesh.reserve(vertices_count, edges_count, faces_count);
for (auto &v : its.vertices)
mesh.add_vertex(typename Mesh::Point{v.x(), v.y(), v.z()});
using VI = typename Mesh::Vertex_index;
for (auto &f : its.indices)
mesh.add_face(VI(f(0)), VI(f(1)), VI(f(2)));
return mesh;
}
indexed_triangle_set mesh_to_its(const Mesh &mesh)
{
indexed_triangle_set res;
res.vertices.reserve(mesh.num_vertices());
res.indices.reserve(mesh.num_faces());
for (auto &vi : mesh.vertices()) {
auto &v = mesh.point(vi); // index addresing, to compare same float point
res.vertices.emplace_back(v.x(),v.y(), v.z());
}
for (auto &face : mesh.faces()) {
auto vtc = mesh.vertices_around_face(mesh.halfedge(face));
int i = 0;
Vec3i facet;
for (auto v : vtc) {
if (i > 2) {
i = 0;
break;
}
facet(i++) = v;
}
if (i == 3) res.indices.emplace_back(facet);
}
return res;
}
void emboss3d_(const Polygon& shape, const EmbossConfig &cfg, indexed_triangle_set &its)
{
indexed_triangle_set shape3d = emboss3d(shape, cfg.height);
//its_write_obj(shape3d,"shape3d.obj");
Mesh m1 = its_to_mesh(its);
Mesh m2 = its_to_mesh(shape3d);
size_t in_vertices_count = its.vertices.size();
size_t in_indices_count = its.indices.size();
auto tt = m1.property_map<Mesh::Edge_index, bool>("e:removed");
Mesh::Property_map<Mesh::Edge_index, bool> ecm1 = tt.first; // hope in copy
PMP::corefine(m1, m2
, PMP::parameters::edge_is_constrained_map(ecm1)
//, PMP::parameters::do_not_modify(true)
);
//PMP::Corefinement::Intersection_of_triangle_meshes()
size_t count_true = 0;
for (const Mesh::Edge_index &e : edges(m1))
if (ecm1[e]) {
++count_true;
const Mesh::Halfedge_index &h = e.halfedge();
const Mesh::Halfedge_index &h2 = m1.opposite(h);
const Mesh::Vertex_index &v = m1.target(h);
std::cout <<
"edge " << e <<
" halfedge " << h <<
" target " << v <<
" index0 " << v.idx() <<
" index1 " << m1.target(h2).idx() <<
std::endl;
}
its = mesh_to_its(m1);
// twice and move additional vertices
Vec3f move = (cfg.projection.normal * cfg.height).cast<float>();
size_t new_add_vertice = its.vertices.size() - in_vertices_count;
its.vertices.reserve(its.vertices.size() + new_add_vertice);
for (size_t i = in_vertices_count; i < its.vertices.size(); ++i)
its.vertices.emplace_back(its.vertices[i] + move);
// zig zag edge collected edge
for (size_t i = in_indices_count; i < its.indices.size(); ++i) {
// new added triangle
Vec3i &t = its.indices[i];
std::array<bool, 3> is_new;
bool is_inner = true;
for (size_t i = 0; i < 3; ++i) {
bool is_n = t[0] >= in_vertices_count;
is_inner |= is_n;
is_new[i] = is_n;
}
}
its_write_obj(mesh_to_its(m1), "corefine1.obj");
its_write_obj(mesh_to_its(m2), "corefine2.obj");
/*MeshBoolean::cgal::CGALMesh cm1 = m1->m;
My_visitor<MeshBoolean::cgal::CGALMesh> sm_v;
CGAL::Polygon_mesh_processing::corefine(m1->m, m2->m,
CGAL::Polygon_mesh_processing::parameters::visitor(sm_v)
, CGAL::parameters::do_not_modify(true)
);*/
//TriangleMesh tm1 = cgal_to_triangle_mesh(*m1);
//store_obj("tm1.obj", &tm1);
//TriangleMesh tm2 = cgal_to_triangle_mesh(*m2);
//store_obj("tm2.obj", &tm1);
its = mesh_to_its(m1);
return;
}
void emboss3d(const Polygon& shape, const EmbossConfig &cfg, indexed_triangle_set &its)
{
indexed_triangle_set shape3d = emboss3d(shape, abs(cfg.height));
//its_write_obj(shape3d,"shape3d.obj");
auto m1 = MeshBoolean::cgal::triangle_mesh_to_cgal(its);
auto m2 = MeshBoolean::cgal::triangle_mesh_to_cgal(shape3d);
bool is_plus = shape.is_counter_clockwise() == (cfg.height > 0.f);
if (is_plus) {
MeshBoolean::cgal::plus(*m1, *m2);
} else {
MeshBoolean::cgal::minus(*m1, *m2);
}
TriangleMesh tm1 = cgal_to_triangle_mesh(*m1);
store_obj("tm1.obj", &tm1);
//TriangleMesh tm2 = cgal_to_triangle_mesh(*m2);
//store_obj("tm2.obj", &tm1);
its = tm1.its; // copy
}
TEST_CASE("Emboss polygon", "[MeshBoolean]")
{
const char *font_name = "C:/windows/fonts/arialbd.ttf";
char letter = '%';
float flatness = 2.;
Polygons polygons = ttf2polygons(font_name, letter, flatness);
store_to_svg(polygons);
//TriangleMesh tm = make_sphere(1., 1.); tm.scale(10.f);
TriangleMesh tm = make_cube(10., 5., 2.);
tm.translate(Vec3f(0, 0, 1.7));
polygons = {Polygon({{1, 1}, {1, 2}, {2, 2}, {2, 1}})}; // rectangle CW
polygons = {Polygon({{1, 1}, {2, 1}, {2, 2}, {1, 2}})}; // rectangle CCW
EmbossConfig ec;
ec.height = 3;
indexed_triangle_set its = tm.its; // copy
for (const auto& polygon : polygons) {
// TODO: differ CW and CCW
emboss3d_(polygon, ec, its);
}
}
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Constrained_Delaunay_triangulation_2.h>
#include <CGAL/Triangulation_vertex_base_with_info_2.h>
// triangulate with constrains on edges
std::vector<Vec3i> triangulate(const std::vector<Vec2f>& points,
const std::vector<std::pair<int, int>>& edges)
{
// use cgal triangulation
using K = CGAL::Exact_predicates_inexact_constructions_kernel;
using Itag = CGAL::Exact_predicates_tag;
using CDT = CGAL::Constrained_Delaunay_triangulation_2<K, CGAL::Default, Itag>;
using Point = CDT::Point;
// construct a constrained triangulation
CDT cdt;
std::map<CDT::Vertex_handle, int> map; // for indices
std::vector<CDT::Vertex_handle> vertices_handle; // for constriants
vertices_handle.reserve(points.size());
for (size_t i = 0; i < points.size(); ++i) {
const Vec2f &p = points[i];
Point cdt_p(p.x(), p.y());
auto handl = cdt.insert(cdt_p);
vertices_handle.push_back(handl);
map[handl] = i;
}
for (const std::pair<int, int> &edge : edges) {
cdt.insert_constraint(vertices_handle[edge.first],
vertices_handle[edge.second]);
}
auto faces = cdt.finite_face_handles();
std::vector<Vec3i> indices;
indices.reserve(faces.size());
for (CDT::Face_handle face : faces){
auto v0 = face->vertex(0);
auto v1 = face->vertex(1);
auto v2 = face->vertex(2);
indices.emplace_back(map[v0], map[v1], map[v2]);
/*
auto p0 = v0->point();
auto p1 = v1->point();
auto p2 = v2->point();
std::cout << "Triangle: " <<
map[v0] << " [" << p0.x() << ", " << p0.y() << "], " <<
map[v1] << " [" << p1.x() << ", " << p1.y() << "], " <<
map[v2] << " [" << p2.x() << ", " << p2.y() << "] " << std::endl;*/
}
return indices;
}
std::vector<Vec3i> triangulate(const Vec3i & triangle,
const Vec3d & triangle_normal,
const std::vector<Vec3f> &vertices,
const TrianglePaths& paths)
{
size_t count_point = 3;
size_t count_circles = 0;
for (const auto &path : paths){
count_point += path.points.size();
if (!path.edges.has_value())
++count_circles;
}
std::vector<Vec3f> points3d;
points3d.reserve(count_point);
std::vector<size_t> index_map;
index_map.reserve(count_point);
// add source triangle points
for (int vi : triangle) {
points3d.push_back(vertices[vi]);
index_map.push_back(vi);
}
// add path points with edges
std::vector<std::pair<int, int>> edges;
edges.reserve(count_point - 3 - paths.size() + count_circles);
for (const auto &path : paths) {
size_t index = path.offset_id;
bool is_first = true;
for (const Vec3f &point : path.points) {
int index = points3d.size();
if (is_first) {
is_first = false;
// all path on triangle
if (!path.edges.has_value())
edges.push_back({index, index + path.points.size()});
} else {
edges.push_back({index-1, index});
}
points3d.push_back(point);
index_map.push_back(index);
++index;
}
}
// TODO:check tr_mat
// create transform matrix to remove z coordinate by normal
const Vec3d z_axis(0, 0, 1);
auto rotation = create_transformation(triangle_normal, z_axis);
// convert points to 2d
std::vector<Vec2f> points_2d;
points_2d.reserve(count_point);
for (const Vec3f &p : points3d) {
Vec3d p_tr = rotation * p.cast<double>();
points_2d.emplace_back(p_tr.x(), p_tr.y());
}
// connecto to triangles
std::vector<Vec3i> indices = triangulate(points_2d, edges);
// TODO: Check thin border triangle caused by float preccision
// remap indexes
for (Vec3i &triangle : indices)
for (int &i : triangle) i = index_map[i];
return indices;
}
TEST_CASE("Triangulate by cgal", "[]")
{
std::vector<Vec2f> points = {
Vec2f(1, 1),
Vec2f(2, 1),
Vec2f(2, 2),
Vec2f(1, 2)
};
std::vector<std::pair<int, int>> edges1 = {{1, 3}};
std::vector<Vec3i> indices1 = triangulate(points, edges1);
auto check = [](int i1, int i2, Vec3i t)->bool { return true;
return (t[0] == i1 || t[1] == i1 || t[2] == i1) &&
(t[0] == i2 || t[1] == i2 || t[2] == i2);
};
REQUIRE(indices1.size() == 2);
int i1 = edges1.front().first,
i2 = edges1.front().second;
CHECK(check(i1, i2, indices1[0]));
CHECK(check(i1, i2, indices1[1]));
std::vector<std::pair<int, int>> edges2 = {{0, 2}};
std::vector<Vec3i> indices2 = triangulate(points, edges2);
REQUIRE(indices2.size() == 2);
i1 = edges2.front().first;
i2 = edges2.front().second;
CHECK(check(i1, i2, indices2[0]));
CHECK(check(i1, i2, indices2[1]));
}