PrusaSlicer-NonPlainar/src/libslic3r/TriangleMesh.cpp
2021-11-30 10:50:27 +01:00

1374 lines
49 KiB
C++

#include "Exception.hpp"
#include "TriangleMesh.hpp"
#include "TriangleMeshSlicer.hpp"
#include "MeshSplitImpl.hpp"
#include "ClipperUtils.hpp"
#include "Geometry.hpp"
#include "Geometry/ConvexHull.hpp"
#include "Point.hpp"
#include "Execution/ExecutionTBB.hpp"
#include "Execution/ExecutionSeq.hpp"
#include "Utils.hpp"
#include <libqhullcpp/Qhull.h>
#include <libqhullcpp/QhullFacetList.h>
#include <libqhullcpp/QhullVertexSet.h>
#include <cmath>
#include <deque>
#include <queue>
#include <vector>
#include <utility>
#include <algorithm>
#include <type_traits>
#include <boost/log/trivial.hpp>
#include <boost/nowide/cstdio.hpp>
#include <boost/predef/other/endian.h>
#include <Eigen/Core>
#include <Eigen/Dense>
#include <assert.h>
namespace Slic3r {
static void update_bounding_box(const indexed_triangle_set &its, TriangleMeshStats &out)
{
BoundingBoxf3 bbox = Slic3r::bounding_box(its);
out.min = bbox.min.cast<float>();
out.max = bbox.max.cast<float>();
out.size = out.max - out.min;
}
static void fill_initial_stats(const indexed_triangle_set &its, TriangleMeshStats &out)
{
out.number_of_facets = its.indices.size();
out.volume = its_volume(its);
update_bounding_box(its, out);
const std::vector<Vec3i> face_neighbors = its_face_neighbors(its);
out.number_of_parts = its_number_of_patches(its, face_neighbors);
out.open_edges = its_num_open_edges(face_neighbors);
}
TriangleMesh::TriangleMesh(const std::vector<Vec3f> &vertices, const std::vector<Vec3i> &faces) : its { faces, vertices }
{
fill_initial_stats(this->its, m_stats);
}
TriangleMesh::TriangleMesh(std::vector<Vec3f> &&vertices, const std::vector<Vec3i> &&faces) : its { std::move(faces), std::move(vertices) }
{
fill_initial_stats(this->its, m_stats);
}
TriangleMesh::TriangleMesh(const indexed_triangle_set &its) : its(its)
{
fill_initial_stats(this->its, m_stats);
}
TriangleMesh::TriangleMesh(indexed_triangle_set &&its, const RepairedMeshErrors& errors/* = RepairedMeshErrors()*/) : its(std::move(its))
{
m_stats.repaired_errors = errors;
fill_initial_stats(this->its, m_stats);
}
// #define SLIC3R_TRACE_REPAIR
static void trianglemesh_repair_on_import(stl_file &stl)
{
// admesh fails when repairing empty meshes
if (stl.stats.number_of_facets == 0)
return;
BOOST_LOG_TRIVIAL(debug) << "TriangleMesh::repair() started";
// checking exact
#ifdef SLIC3R_TRACE_REPAIR
BOOST_LOG_TRIVIAL(trace) << "\tstl_check_faces_exact";
#endif /* SLIC3R_TRACE_REPAIR */
assert(stl_validate(&stl));
stl_check_facets_exact(&stl);
assert(stl_validate(&stl));
stl.stats.facets_w_1_bad_edge = (stl.stats.connected_facets_2_edge - stl.stats.connected_facets_3_edge);
stl.stats.facets_w_2_bad_edge = (stl.stats.connected_facets_1_edge - stl.stats.connected_facets_2_edge);
stl.stats.facets_w_3_bad_edge = (stl.stats.number_of_facets - stl.stats.connected_facets_1_edge);
// checking nearby
//int last_edges_fixed = 0;
float tolerance = (float)stl.stats.shortest_edge;
float increment = (float)stl.stats.bounding_diameter / 10000.0f;
int iterations = 2;
if (stl.stats.connected_facets_3_edge < int(stl.stats.number_of_facets)) {
// Not a manifold, some triangles have unconnected edges.
for (int i = 0; i < iterations; ++ i) {
if (stl.stats.connected_facets_3_edge < int(stl.stats.number_of_facets)) {
// Still not a manifold, some triangles have unconnected edges.
//printf("Checking nearby. Tolerance= %f Iteration=%d of %d...", tolerance, i + 1, iterations);
#ifdef SLIC3R_TRACE_REPAIR
BOOST_LOG_TRIVIAL(trace) << "\tstl_check_faces_nearby";
#endif /* SLIC3R_TRACE_REPAIR */
stl_check_facets_nearby(&stl, tolerance);
//printf(" Fixed %d edges.\n", stl.stats.edges_fixed - last_edges_fixed);
//last_edges_fixed = stl.stats.edges_fixed;
tolerance += increment;
} else {
break;
}
}
}
assert(stl_validate(&stl));
// remove_unconnected
if (stl.stats.connected_facets_3_edge < (int)stl.stats.number_of_facets) {
#ifdef SLIC3R_TRACE_REPAIR
BOOST_LOG_TRIVIAL(trace) << "\tstl_remove_unconnected_facets";
#endif /* SLIC3R_TRACE_REPAIR */
stl_remove_unconnected_facets(&stl);
assert(stl_validate(&stl));
}
// fill_holes
#if 0
// Don't fill holes, the current algorithm does more harm than good on complex holes.
// Rather let the slicing algorithm close gaps in 2D slices.
if (stl.stats.connected_facets_3_edge < stl.stats.number_of_facets) {
#ifdef SLIC3R_TRACE_REPAIR
BOOST_LOG_TRIVIAL(trace) << "\tstl_fill_holes";
#endif /* SLIC3R_TRACE_REPAIR */
stl_fill_holes(&stl);
stl_clear_error(&stl);
}
#endif
// normal_directions
#ifdef SLIC3R_TRACE_REPAIR
BOOST_LOG_TRIVIAL(trace) << "\tstl_fix_normal_directions";
#endif /* SLIC3R_TRACE_REPAIR */
stl_fix_normal_directions(&stl);
assert(stl_validate(&stl));
// normal_values
#ifdef SLIC3R_TRACE_REPAIR
BOOST_LOG_TRIVIAL(trace) << "\tstl_fix_normal_values";
#endif /* SLIC3R_TRACE_REPAIR */
stl_fix_normal_values(&stl);
assert(stl_validate(&stl));
// always calculate the volume and reverse all normals if volume is negative
#ifdef SLIC3R_TRACE_REPAIR
BOOST_LOG_TRIVIAL(trace) << "\tstl_calculate_volume";
#endif /* SLIC3R_TRACE_REPAIR */
// If the volume is negative, all the facets are flipped and added to stats.facets_reversed.
stl_calculate_volume(&stl);
assert(stl_validate(&stl));
// neighbors
#ifdef SLIC3R_TRACE_REPAIR
BOOST_LOG_TRIVIAL(trace) << "\tstl_verify_neighbors";
#endif /* SLIC3R_TRACE_REPAIR */
stl_verify_neighbors(&stl);
assert(stl_validate(&stl));
//FIXME The admesh repair function may break the face connectivity, rather refresh it here as the slicing code relies on it.
if (auto nr_degenerated = stl.stats.degenerate_facets; stl.stats.number_of_facets > 0 && nr_degenerated > 0)
stl_check_facets_exact(&stl);
BOOST_LOG_TRIVIAL(debug) << "TriangleMesh::repair() finished";
}
bool TriangleMesh::ReadSTLFile(const char* input_file, bool repair)
{
stl_file stl;
if (! stl_open(&stl, input_file))
return false;
if (repair)
trianglemesh_repair_on_import(stl);
m_stats.number_of_facets = stl.stats.number_of_facets;
m_stats.min = stl.stats.min;
m_stats.max = stl.stats.max;
m_stats.size = stl.stats.size;
m_stats.volume = stl.stats.volume;
auto facets_w_1_bad_edge = stl.stats.connected_facets_2_edge - stl.stats.connected_facets_3_edge;
auto facets_w_2_bad_edge = stl.stats.connected_facets_1_edge - stl.stats.connected_facets_2_edge;
auto facets_w_3_bad_edge = stl.stats.number_of_facets - stl.stats.connected_facets_1_edge;
m_stats.open_edges = stl.stats.backwards_edges + facets_w_1_bad_edge + facets_w_2_bad_edge * 2 + facets_w_3_bad_edge * 3;
m_stats.repaired_errors = { stl.stats.edges_fixed,
stl.stats.degenerate_facets,
stl.stats.facets_removed,
stl.stats.facets_reversed,
stl.stats.backwards_edges };
m_stats.number_of_parts = stl.stats.number_of_parts;
stl_generate_shared_vertices(&stl, this->its);
return true;
}
bool TriangleMesh::write_ascii(const char* output_file)
{
return its_write_stl_ascii(output_file, "", this->its);
}
bool TriangleMesh::write_binary(const char* output_file)
{
return its_write_stl_binary(output_file, "", this->its);
}
float TriangleMesh::volume()
{
if (m_stats.volume == -1)
m_stats.volume = its_volume(this->its);
return m_stats.volume;
}
void TriangleMesh::WriteOBJFile(const char* output_file) const
{
its_write_obj(this->its, output_file);
}
void TriangleMesh::scale(float factor)
{
this->scale(Vec3f(factor, factor, factor));
}
void TriangleMesh::scale(const Vec3f &versor)
{
// Scale extents.
auto s = versor.array();
m_stats.min.array() *= s;
m_stats.max.array() *= s;
// Scale size.
m_stats.size.array() *= s;
// Scale volume.
if (m_stats.volume > 0.0)
m_stats.volume *= s(0) * s(1) * s(2);
if (versor.x() == versor.y() && versor.x() == versor.z()) {
float s = versor.x();
for (stl_vertex &v : this->its.vertices)
v *= s;
} else {
for (stl_vertex &v : this->its.vertices) {
v.x() *= versor.x();
v.y() *= versor.y();
v.z() *= versor.z();
}
}
}
void TriangleMesh::translate(const Vec3f &displacement)
{
if (displacement.x() != 0.f || displacement.y() != 0.f || displacement.z() != 0.f) {
for (stl_vertex& v : this->its.vertices)
v += displacement;
m_stats.min += displacement;
m_stats.max += displacement;
}
}
void TriangleMesh::translate(float x, float y, float z)
{
this->translate(Vec3f(x, y, z));
}
void TriangleMesh::rotate(float angle, const Axis &axis)
{
if (angle != 0.f) {
angle = Slic3r::Geometry::rad2deg(angle);
switch (axis) {
case X: its_rotate_x(this->its, angle); break;
case Y: its_rotate_y(this->its, angle); break;
case Z: its_rotate_z(this->its, angle); break;
default: assert(false); return;
}
update_bounding_box(this->its, this->m_stats);
}
}
void TriangleMesh::rotate(float angle, const Vec3d& axis)
{
if (angle != 0.f) {
Vec3d axis_norm = axis.normalized();
Transform3d m = Transform3d::Identity();
m.rotate(Eigen::AngleAxisd(angle, axis_norm));
its_transform(its, m);
update_bounding_box(this->its, this->m_stats);
}
}
void TriangleMesh::mirror(const Axis axis)
{
switch (axis) {
case X:
for (stl_vertex &v : its.vertices)
v.x() *= -1.f;
break;
case Y:
for (stl_vertex& v : this->its.vertices)
v.y() *= -1.0;
break;
case Z:
for (stl_vertex &v : this->its.vertices)
v.z() *= -1.0;
break;
default:
assert(false);
return;
};
its_flip_triangles(this->its);
int iaxis = int(axis);
std::swap(m_stats.min[iaxis], m_stats.max[iaxis]);
m_stats.min[iaxis] *= -1.0;
m_stats.max[iaxis] *= -1.0;
}
void TriangleMesh::transform(const Transform3d& t, bool fix_left_handed)
{
its_transform(its, t);
double det = t.matrix().block(0, 0, 3, 3).determinant();
if (fix_left_handed && det < 0.) {
its_flip_triangles(its);
det = -det;
}
m_stats.volume *= det;
update_bounding_box(this->its, this->m_stats);
}
void TriangleMesh::transform(const Matrix3d& m, bool fix_left_handed)
{
its_transform(its, m);
double det = m.block(0, 0, 3, 3).determinant();
if (fix_left_handed && det < 0.) {
its_flip_triangles(its);
det = -det;
}
m_stats.volume *= det;
update_bounding_box(this->its, this->m_stats);
}
void TriangleMesh::flip_triangles()
{
its_flip_triangles(its);
m_stats.volume = - m_stats.volume;
}
void TriangleMesh::align_to_origin()
{
this->translate(- m_stats.min(0), - m_stats.min(1), - m_stats.min(2));
}
void TriangleMesh::rotate(double angle, Point* center)
{
if (angle != 0.) {
Vec2f c = center->cast<float>();
this->translate(-c(0), -c(1), 0);
its_rotate_z(this->its, (float)angle);
this->translate(c(0), c(1), 0);
}
}
/**
* Calculates whether or not the mesh is splittable.
*/
bool TriangleMesh::is_splittable() const
{
return its_is_splittable(this->its);
}
std::vector<TriangleMesh> TriangleMesh::split() const
{
std::vector<indexed_triangle_set> itss = its_split(this->its);
std::vector<TriangleMesh> out;
out.reserve(itss.size());
for (indexed_triangle_set &m : itss) {
// The TriangleMesh constructor shall fill in the mesh statistics including volume.
out.emplace_back(std::move(m));
if (TriangleMesh &triangle_mesh = out.back(); triangle_mesh.volume() < 0)
// Some source mesh parts may be incorrectly oriented. Correct them.
triangle_mesh.flip_triangles();
}
return out;
}
void TriangleMesh::merge(const TriangleMesh &mesh)
{
its_merge(this->its, mesh.its);
m_stats = m_stats.merge(mesh.m_stats);
}
// Calculate projection of the mesh into the XY plane, in scaled coordinates.
//FIXME This could be extremely slow! Use it for tiny meshes only!
ExPolygons TriangleMesh::horizontal_projection() const
{
return union_ex(project_mesh(this->its, Transform3d::Identity(), []() {}));
}
// 2D convex hull of a 3D mesh projected into the Z=0 plane.
Polygon TriangleMesh::convex_hull()
{
Points pp;
pp.reserve(this->its.vertices.size());
for (size_t i = 0; i < this->its.vertices.size(); ++ i) {
const stl_vertex &v = this->its.vertices[i];
pp.emplace_back(Point::new_scale(v(0), v(1)));
}
return Slic3r::Geometry::convex_hull(pp);
}
BoundingBoxf3 TriangleMesh::bounding_box() const
{
BoundingBoxf3 bb;
bb.defined = true;
bb.min = m_stats.min.cast<double>();
bb.max = m_stats.max.cast<double>();
return bb;
}
BoundingBoxf3 TriangleMesh::transformed_bounding_box(const Transform3d &trafo) const
{
BoundingBoxf3 bbox;
for (const stl_vertex &v : this->its.vertices)
bbox.merge(trafo * v.cast<double>());
return bbox;
}
BoundingBoxf3 TriangleMesh::transformed_bounding_box(const Transform3d& trafod, double world_min_z) const
{
// 1) Allocate transformed vertices with their position with respect to print bed surface.
std::vector<char> sides;
size_t num_above = 0;
Eigen::AlignedBox<float, 3> bbox;
Transform3f trafo = trafod.cast<float>();
sides.reserve(its.vertices.size());
for (const stl_vertex &v : this->its.vertices) {
const stl_vertex pt = trafo * v;
const int sign = pt.z() > world_min_z ? 1 : pt.z() < world_min_z ? -1 : 0;
sides.emplace_back(sign);
if (sign >= 0) {
// Vertex above or on print bed surface. Test whether it is inside the build volume.
++ num_above;
bbox.extend(pt);
}
}
// 2) Calculate intersections of triangle edges with the build surface.
if (num_above < its.vertices.size()) {
// Not completely above the build surface and status may still change by testing edges intersecting the build platform.
for (const stl_triangle_vertex_indices &tri : its.indices) {
const int s[3] = { sides[tri(0)], sides[tri(1)], sides[tri(2)] };
if (std::min(s[0], std::min(s[1], s[2])) < 0 && std::max(s[0], std::max(s[1], s[2])) > 0) {
// Some edge of this triangle intersects the build platform. Calculate the intersection.
int iprev = 2;
for (int iedge = 0; iedge < 3; ++ iedge) {
if (s[iprev] * s[iedge] == -1) {
// edge intersects the build surface. Calculate intersection point.
const stl_vertex p1 = trafo * its.vertices[tri(iprev)];
const stl_vertex p2 = trafo * its.vertices[tri(iedge)];
// Edge crosses the z plane. Calculate intersection point with the plane.
const float t = (world_min_z - p1.z()) / (p2.z() - p1.z());
bbox.extend(Vec3f(p1.x() + (p2.x() - p1.x()) * t, p1.y() + (p2.y() - p1.y()) * t, world_min_z));
}
iprev = iedge;
}
}
}
}
BoundingBoxf3 out;
if (! bbox.isEmpty()) {
out.min = bbox.min().cast<double>();
out.max = bbox.max().cast<double>();
out.defined = true;
};
return out;
}
TriangleMesh TriangleMesh::convex_hull_3d() const
{
TriangleMesh mesh(its_convex_hull(this->its));
// Quite often qhull produces non-manifold mesh.
// assert(mesh.stats().manifold());
return mesh;
}
std::vector<ExPolygons> TriangleMesh::slice(const std::vector<double> &z) const
{
// convert doubles to floats
std::vector<float> z_f(z.begin(), z.end());
return slice_mesh_ex(this->its, z_f, 0.0004f);
}
size_t TriangleMesh::memsize() const
{
size_t memsize = 8 + this->its.memsize() + sizeof(this->m_stats);
return memsize;
}
// Create a mapping from triangle edge into face.
struct EdgeToFace {
// Index of the 1st vertex of the triangle edge. vertex_low <= vertex_high.
int vertex_low;
// Index of the 2nd vertex of the triangle edge.
int vertex_high;
// Index of a triangular face.
int face;
// Index of edge in the face, starting with 1. Negative indices if the edge was stored reverse in (vertex_low, vertex_high).
int face_edge;
bool operator==(const EdgeToFace &other) const { return vertex_low == other.vertex_low && vertex_high == other.vertex_high; }
bool operator<(const EdgeToFace &other) const { return vertex_low < other.vertex_low || (vertex_low == other.vertex_low && vertex_high < other.vertex_high); }
};
template<typename FaceFilter, typename ThrowOnCancelCallback>
static std::vector<EdgeToFace> create_edge_map(
const indexed_triangle_set &its, FaceFilter face_filter, ThrowOnCancelCallback throw_on_cancel)
{
std::vector<EdgeToFace> edges_map;
edges_map.reserve(its.indices.size() * 3);
for (uint32_t facet_idx = 0; facet_idx < its.indices.size(); ++ facet_idx)
if (face_filter(facet_idx))
for (int i = 0; i < 3; ++ i) {
edges_map.push_back({});
EdgeToFace &e2f = edges_map.back();
e2f.vertex_low = its.indices[facet_idx][i];
e2f.vertex_high = its.indices[facet_idx][(i + 1) % 3];
e2f.face = facet_idx;
// 1 based indexing, to be always strictly positive.
e2f.face_edge = i + 1;
if (e2f.vertex_low > e2f.vertex_high) {
// Sort the vertices
std::swap(e2f.vertex_low, e2f.vertex_high);
// and make the face_edge negative to indicate a flipped edge.
e2f.face_edge = - e2f.face_edge;
}
}
throw_on_cancel();
std::sort(edges_map.begin(), edges_map.end());
return edges_map;
}
// Map from a face edge to a unique edge identifier or -1 if no neighbor exists.
// Two neighbor faces share a unique edge identifier even if they are flipped.
template<typename FaceFilter, typename ThrowOnCancelCallback>
static inline std::vector<Vec3i> its_face_edge_ids_impl(const indexed_triangle_set &its, FaceFilter face_filter, ThrowOnCancelCallback throw_on_cancel)
{
std::vector<Vec3i> out(its.indices.size(), Vec3i(-1, -1, -1));
std::vector<EdgeToFace> edges_map = create_edge_map(its, face_filter, throw_on_cancel);
// Assign a unique common edge id to touching triangle edges.
int num_edges = 0;
for (size_t i = 0; i < edges_map.size(); ++ i) {
EdgeToFace &edge_i = edges_map[i];
if (edge_i.face == -1)
// This edge has been connected to some neighbor already.
continue;
// Unconnected edge. Find its neighbor with the correct orientation.
size_t j;
bool found = false;
for (j = i + 1; j < edges_map.size() && edge_i == edges_map[j]; ++ j)
if (edge_i.face_edge * edges_map[j].face_edge < 0 && edges_map[j].face != -1) {
// Faces touching with opposite oriented edges and none of the edges is connected yet.
found = true;
break;
}
if (! found) {
//FIXME Vojtech: Trying to find an edge with equal orientation. This smells.
// admesh can assign the same edge ID to more than two facets (which is
// still topologically correct), so we have to search for a duplicate of
// this edge too in case it was already seen in this orientation
for (j = i + 1; j < edges_map.size() && edge_i == edges_map[j]; ++ j)
if (edges_map[j].face != -1) {
// Faces touching with equally oriented edges and none of the edges is connected yet.
found = true;
break;
}
}
// Assign an edge index to the 1st face.
out[edge_i.face](std::abs(edge_i.face_edge) - 1) = num_edges;
if (found) {
EdgeToFace &edge_j = edges_map[j];
out[edge_j.face](std::abs(edge_j.face_edge) - 1) = num_edges;
// Mark the edge as connected.
edge_j.face = -1;
}
++ num_edges;
if ((i & 0x0ffff) == 0)
throw_on_cancel();
}
return out;
}
std::vector<Vec3i> its_face_edge_ids(const indexed_triangle_set &its)
{
return its_face_edge_ids_impl(its, [](const uint32_t){ return true; }, [](){});
}
std::vector<Vec3i> its_face_edge_ids(const indexed_triangle_set &its, std::function<void()> throw_on_cancel_callback)
{
return its_face_edge_ids_impl(its, [](const uint32_t){ return true; }, throw_on_cancel_callback);
}
std::vector<Vec3i> its_face_edge_ids(const indexed_triangle_set &its, const std::vector<bool> &face_mask)
{
return its_face_edge_ids_impl(its, [&face_mask](const uint32_t idx){ return face_mask[idx]; }, [](){});
}
// Having the face neighbors available, assign unique edge IDs to face edges for chaining of polygons over slices.
std::vector<Vec3i> its_face_edge_ids(const indexed_triangle_set &its, std::vector<Vec3i> &face_neighbors, bool assign_unbound_edges, int *num_edges)
{
// out elements are not initialized!
std::vector<Vec3i> out(face_neighbors.size());
int last_edge_id = 0;
for (int i = 0; i < int(face_neighbors.size()); ++ i) {
const stl_triangle_vertex_indices &triangle = its.indices[i];
const Vec3i &neighbors = face_neighbors[i];
for (int j = 0; j < 3; ++ j) {
int n = neighbors[j];
if (n > i) {
const stl_triangle_vertex_indices &triangle2 = its.indices[n];
int edge_id = last_edge_id ++;
Vec2i edge = its_triangle_edge(triangle, j);
// First find an edge with opposite orientation.
std::swap(edge(0), edge(1));
int k = its_triangle_edge_index(triangle2, edge);
//FIXME is the following realistic? Could face_neighbors contain such faces?
// And if it does, do we want to produce the same edge ID for those mutually incorrectly oriented edges?
if (k == -1) {
// Second find an edge with the same orientation (the neighbor triangle may be flipped).
std::swap(edge(0), edge(1));
k = its_triangle_edge_index(triangle2, edge);
}
assert(k >= 0);
out[i](j) = edge_id;
out[n](k) = edge_id;
} else if (n == -1) {
out[i](j) = assign_unbound_edges ? last_edge_id ++ : -1;
} else {
// Triangle shall never be neighbor of itself.
assert(n < i);
// Don't do anything, the neighbor will assign us an edge ID in later iterations.
}
}
}
if (num_edges)
*num_edges = last_edge_id;
return out;
}
// Merge duplicate vertices, return number of vertices removed.
int its_merge_vertices(indexed_triangle_set &its, bool shrink_to_fit)
{
// 1) Sort indices to vertices lexicographically by coordinates AND vertex index.
auto sorted = reserve_vector<int>(its.vertices.size());
for (int i = 0; i < int(its.vertices.size()); ++ i)
sorted.emplace_back(i);
std::sort(sorted.begin(), sorted.end(), [&its](int il, int ir) {
const Vec3f &l = its.vertices[il];
const Vec3f &r = its.vertices[ir];
// Sort lexicographically by coordinates AND vertex index.
return l.x() < r.x() || (l.x() == r.x() && (l.y() < r.y() || (l.y() == r.y() && (l.z() < r.z() || (l.z() == r.z() && il < ir)))));
});
// 2) Map duplicate vertices to the one with the lowest vertex index.
// The vertex to stay will have a map_vertices[...] == -1 index assigned, the other vertices will point to it.
std::vector<int> map_vertices(its.vertices.size(), -1);
for (int i = 0; i < int(sorted.size());) {
const int u = sorted[i];
const Vec3f &p = its.vertices[u];
int j = i;
for (++ j; j < int(sorted.size()); ++ j) {
const int v = sorted[j];
const Vec3f &q = its.vertices[v];
if (p != q)
break;
assert(v > u);
map_vertices[v] = u;
}
i = j;
}
// 3) Shrink its.vertices, update map_vertices with the new vertex indices.
int k = 0;
for (int i = 0; i < int(its.vertices.size()); ++ i) {
if (map_vertices[i] == -1) {
map_vertices[i] = k;
if (k < i)
its.vertices[k] = its.vertices[i];
++ k;
} else {
assert(map_vertices[i] < i);
map_vertices[i] = map_vertices[map_vertices[i]];
}
}
int num_erased = int(its.vertices.size()) - k;
if (num_erased) {
// Shrink the vertices.
its.vertices.erase(its.vertices.begin() + k, its.vertices.end());
// Remap face indices.
for (stl_triangle_vertex_indices &face : its.indices)
for (int i = 0; i < 3; ++ i)
face(i) = map_vertices[face(i)];
// Optionally shrink to fit (reallocate) vertices.
if (shrink_to_fit)
its.vertices.shrink_to_fit();
}
return num_erased;
}
void its_flip_triangles(indexed_triangle_set &its)
{
for (stl_triangle_vertex_indices &face : its.indices)
std::swap(face(1), face(2));
}
int its_remove_degenerate_faces(indexed_triangle_set &its, bool shrink_to_fit)
{
auto it = std::remove_if(its.indices.begin(), its.indices.end(), [](auto &face) {
return face(0) == face(1) || face(0) == face(2) || face(1) == face(2);
});
int removed = std::distance(it, its.indices.end());
its.indices.erase(it, its.indices.end());
if (removed && shrink_to_fit)
its.indices.shrink_to_fit();
return removed;
}
int its_compactify_vertices(indexed_triangle_set &its, bool shrink_to_fit)
{
// First used to mark referenced vertices, later used for mapping old vertex index to a new one.
std::vector<int> vertex_map(its.vertices.size(), 0);
// Mark referenced vertices.
for (const stl_triangle_vertex_indices &face : its.indices)
for (int i = 0; i < 3; ++ i)
vertex_map[face(i)] = 1;
// Compactify vertices, update map from old vertex index to a new one.
int last = 0;
for (int i = 0; i < int(vertex_map.size()); ++ i)
if (vertex_map[i]) {
if (last < i)
its.vertices[last] = its.vertices[i];
vertex_map[i] = last ++;
}
int removed = int(its.vertices.size()) - last;
if (removed) {
its.vertices.erase(its.vertices.begin() + last, its.vertices.end());
// Update faces with the new vertex indices.
for (stl_triangle_vertex_indices &face : its.indices)
for (int i = 0; i < 3; ++ i)
face(i) = vertex_map[face(i)];
// Optionally shrink the vertices.
if (shrink_to_fit)
its.vertices.shrink_to_fit();
}
return removed;
}
bool its_store_triangle(const indexed_triangle_set &its,
const char * obj_filename,
size_t triangle_index)
{
if (its.indices.size() <= triangle_index) return false;
Vec3i t = its.indices[triangle_index];
indexed_triangle_set its2;
its2.indices = {{0, 1, 2}};
its2.vertices = {its.vertices[t[0]], its.vertices[t[1]],
its.vertices[t[2]]};
return its_write_obj(its2, obj_filename);
}
bool its_store_triangles(const indexed_triangle_set &its,
const char * obj_filename,
const std::vector<size_t> & triangles)
{
indexed_triangle_set its2;
its2.vertices.reserve(triangles.size() * 3);
its2.indices.reserve(triangles.size());
std::map<size_t, size_t> vertex_map;
for (auto ti : triangles) {
if (its.indices.size() <= ti) return false;
Vec3i t = its.indices[ti];
Vec3i new_t;
for (size_t i = 0; i < 3; ++i) {
size_t vi = t[i];
auto it = vertex_map.find(vi);
if (it != vertex_map.end()) {
new_t[i] = it->second;
continue;
}
size_t new_vi = its2.vertices.size();
its2.vertices.push_back(its.vertices[vi]);
vertex_map[vi] = new_vi;
new_t[i] = new_vi;
}
its2.indices.push_back(new_t);
}
return its_write_obj(its2, obj_filename);
}
void its_shrink_to_fit(indexed_triangle_set &its)
{
its.indices.shrink_to_fit();
its.vertices.shrink_to_fit();
}
template<typename TransformVertex>
void its_collect_mesh_projection_points_above(const indexed_triangle_set &its, const TransformVertex &transform_fn, const float z, Points &all_pts)
{
all_pts.reserve(all_pts.size() + its.indices.size() * 3);
for (const stl_triangle_vertex_indices &tri : its.indices) {
const Vec3f pts[3] = { transform_fn(its.vertices[tri(0)]), transform_fn(its.vertices[tri(1)]), transform_fn(its.vertices[tri(2)]) };
int iprev = 2;
for (int iedge = 0; iedge < 3; ++ iedge) {
const Vec3f &p1 = pts[iprev];
const Vec3f &p2 = pts[iedge];
if ((p1.z() < z && p2.z() > z) || (p2.z() < z && p1.z() > z)) {
// Edge crosses the z plane. Calculate intersection point with the plane.
float t = (z - p1.z()) / (p2.z() - p1.z());
all_pts.emplace_back(scaled<coord_t>(p1.x() + (p2.x() - p1.x()) * t), scaled<coord_t>(p1.y() + (p2.y() - p1.y()) * t));
}
if (p2.z() >= z)
all_pts.emplace_back(scaled<coord_t>(p2.x()), scaled<coord_t>(p2.y()));
iprev = iedge;
}
}
}
void its_collect_mesh_projection_points_above(const indexed_triangle_set &its, const Matrix3f &m, const float z, Points &all_pts)
{
return its_collect_mesh_projection_points_above(its, [m](const Vec3f &p){ return m * p; }, z, all_pts);
}
void its_collect_mesh_projection_points_above(const indexed_triangle_set &its, const Transform3f &t, const float z, Points &all_pts)
{
return its_collect_mesh_projection_points_above(its, [t](const Vec3f &p){ return t * p; }, z, all_pts);
}
template<typename TransformVertex>
Polygon its_convex_hull_2d_above(const indexed_triangle_set &its, const TransformVertex &transform_fn, const float z)
{
Points all_pts;
its_collect_mesh_projection_points_above(its, transform_fn, z, all_pts);
return Geometry::convex_hull(std::move(all_pts));
}
Polygon its_convex_hull_2d_above(const indexed_triangle_set &its, const Matrix3f &m, const float z)
{
return its_convex_hull_2d_above(its, [m](const Vec3f &p){ return m * p; }, z);
}
Polygon its_convex_hull_2d_above(const indexed_triangle_set &its, const Transform3f &t, const float z)
{
return its_convex_hull_2d_above(its, [t](const Vec3f &p){ return t * p; }, z);
}
// Generate the vertex list for a cube solid of arbitrary size in X/Y/Z.
indexed_triangle_set its_make_cube(double xd, double yd, double zd)
{
auto x = float(xd), y = float(yd), z = float(zd);
return {
{ {0, 1, 2}, {0, 2, 3}, {4, 5, 6}, {4, 6, 7},
{0, 4, 7}, {0, 7, 1}, {1, 7, 6}, {1, 6, 2},
{2, 6, 5}, {2, 5, 3}, {4, 0, 3}, {4, 3, 5} },
{ {x, y, 0}, {x, 0, 0}, {0, 0, 0}, {0, y, 0},
{x, y, z}, {0, y, z}, {0, 0, z}, {x, 0, z} }
};
}
indexed_triangle_set its_make_prism(float width, float length, float height)
{
// We need two upward facing triangles
float x = width / 2.f, y = length / 2.f;
return {
{
{0, 1, 2}, // side 1
{4, 3, 5}, // side 2
{1, 4, 2}, {2, 4, 5}, // roof 1
{0, 2, 5}, {0, 5, 3}, // roof 2
{3, 4, 1}, {3, 1, 0} // bottom
},
{
{-x, -y, 0.f}, {x, -y, 0.f}, {0.f, -y, height},
{-x, y, 0.f}, {x, y, 0.f}, {0.f, y, height},
}
};
}
// Generate the mesh for a cylinder and return it, using
// the generated angle to calculate the top mesh triangles.
// Default is 360 sides, angle fa is in radians.
indexed_triangle_set its_make_cylinder(double r, double h, double fa)
{
indexed_triangle_set mesh;
size_t n_steps = (size_t)ceil(2. * PI / fa);
double angle_step = 2. * PI / n_steps;
auto &vertices = mesh.vertices;
auto &facets = mesh.indices;
vertices.reserve(2 * n_steps + 2);
facets.reserve(4 * n_steps);
// 2 special vertices, top and bottom center, rest are relative to this
vertices.emplace_back(Vec3f(0.f, 0.f, 0.f));
vertices.emplace_back(Vec3f(0.f, 0.f, float(h)));
// for each line along the polygon approximating the top/bottom of the
// circle, generate four points and four facets (2 for the wall, 2 for the
// top and bottom.
// Special case: Last line shares 2 vertices with the first line.
Vec2f p = Eigen::Rotation2Df(0.f) * Eigen::Vector2f(0, r);
vertices.emplace_back(Vec3f(p(0), p(1), 0.f));
vertices.emplace_back(Vec3f(p(0), p(1), float(h)));
for (size_t i = 1; i < n_steps; ++i) {
p = Eigen::Rotation2Df(angle_step * i) * Eigen::Vector2f(0, float(r));
vertices.emplace_back(Vec3f(p(0), p(1), 0.f));
vertices.emplace_back(Vec3f(p(0), p(1), float(h)));
int id = (int)vertices.size() - 1;
facets.emplace_back( 0, id - 1, id - 3); // top
facets.emplace_back(id, 1, id - 2); // bottom
facets.emplace_back(id, id - 2, id - 3); // upper-right of side
facets.emplace_back(id, id - 3, id - 1); // bottom-left of side
}
// Connect the last set of vertices with the first.
int id = (int)vertices.size() - 1;
facets.emplace_back( 0, 2, id - 1);
facets.emplace_back( 3, 1, id);
facets.emplace_back(id, 2, 3);
facets.emplace_back(id, id - 1, 2);
return mesh;
}
indexed_triangle_set its_make_cone(double r, double h, double fa)
{
indexed_triangle_set mesh;
auto& vertices = mesh.vertices;
auto& facets = mesh.indices;
vertices.reserve(3 + 2 * size_t(2 * PI / fa));
// base center and top vertex
vertices.emplace_back(Vec3f::Zero());
vertices.emplace_back(Vec3f(0., 0., h));
size_t i = 0;
for (double angle=0; angle<2*PI; angle+=fa) {
vertices.emplace_back(r*std::cos(angle), r*std::sin(angle), 0.);
if (angle > 0.) {
facets.emplace_back(0, i+2, i+1);
facets.emplace_back(1, i+1, i+2);
}
++i;
}
facets.emplace_back(0, 2, i+1); // close the shape
facets.emplace_back(1, i+1, 2);
return mesh;
}
indexed_triangle_set its_make_pyramid(float base, float height)
{
float a = base / 2.f;
return {
{
{0, 1, 2},
{0, 2, 3},
{0, 1, 4},
{1, 2, 4},
{2, 3, 4},
{3, 0, 4}
},
{
{-a, -a, 0}, {a, -a, 0}, {a, a, 0},
{-a, a, 0}, {0.f, 0.f, height}
}
};
}
// Generates mesh for a sphere centered about the origin, using the generated angle
// to determine the granularity.
// Default angle is 1 degree.
//FIXME better to discretize an Icosahedron recursively http://www.songho.ca/opengl/gl_sphere.html
indexed_triangle_set its_make_sphere(double radius, double fa)
{
int sectorCount = int(ceil(2. * M_PI / fa));
int stackCount = int(ceil(M_PI / fa));
float sectorStep = float(2. * M_PI / sectorCount);
float stackStep = float(M_PI / stackCount);
indexed_triangle_set mesh;
auto& vertices = mesh.vertices;
vertices.reserve((stackCount - 1) * sectorCount + 2);
for (int i = 0; i <= stackCount; ++ i) {
// from pi/2 to -pi/2
double stackAngle = 0.5 * M_PI - stackStep * i;
double xy = radius * cos(stackAngle);
double z = radius * sin(stackAngle);
if (i == 0 || i == stackCount)
vertices.emplace_back(Vec3f(float(xy), 0.f, float(z)));
else
for (int j = 0; j < sectorCount; ++ j) {
// from 0 to 2pi
double sectorAngle = sectorStep * j;
vertices.emplace_back(Vec3d(xy * std::cos(sectorAngle), xy * std::sin(sectorAngle), z).cast<float>());
}
}
auto& facets = mesh.indices;
facets.reserve(2 * (stackCount - 1) * sectorCount);
for (int i = 0; i < stackCount; ++ i) {
// Beginning of current stack.
int k1 = (i == 0) ? 0 : (1 + (i - 1) * sectorCount);
int k1_first = k1;
// Beginning of next stack.
int k2 = (i == 0) ? 1 : (k1 + sectorCount);
int k2_first = k2;
for (int j = 0; j < sectorCount; ++ j) {
// 2 triangles per sector excluding first and last stacks
int k1_next = k1;
int k2_next = k2;
if (i != 0) {
k1_next = (j + 1 == sectorCount) ? k1_first : (k1 + 1);
facets.emplace_back(k1, k2, k1_next);
}
if (i + 1 != stackCount) {
k2_next = (j + 1 == sectorCount) ? k2_first : (k2 + 1);
facets.emplace_back(k1_next, k2, k2_next);
}
k1 = k1_next;
k2 = k2_next;
}
}
return mesh;
}
indexed_triangle_set its_convex_hull(const std::vector<Vec3f> &pts)
{
std::vector<Vec3f> dst_vertices;
std::vector<Vec3i> dst_facets;
if (! pts.empty()) {
// The qhull call:
orgQhull::Qhull qhull;
qhull.disableOutputStream(); // we want qhull to be quiet
#if ! REALfloat
std::vector<realT> src_vertices;
#endif
try {
#if REALfloat
qhull.runQhull("", 3, (int)pts.size(), (const realT*)(pts.front().data()), "Qt");
#else
src_vertices.reserve(pts.size() * 3);
// We will now fill the vector with input points for computation:
for (const stl_vertex &v : pts)
for (int i = 0; i < 3; ++ i)
src_vertices.emplace_back(v(i));
qhull.runQhull("", 3, (int)src_vertices.size() / 3, src_vertices.data(), "Qt");
#endif
} catch (...) {
BOOST_LOG_TRIVIAL(error) << "its_convex_hull: Unable to create convex hull";
return {};
}
// Let's collect results:
// Map of QHull's vertex ID to our own vertex ID (pointing to dst_vertices).
std::vector<int> map_dst_vertices;
#ifndef NDEBUG
Vec3f centroid = Vec3f::Zero();
for (const stl_vertex& pt : pts)
centroid += pt;
centroid /= float(pts.size());
#endif // NDEBUG
for (const orgQhull::QhullFacet &facet : qhull.facetList()) {
// Collect face vertices first, allocate unique vertices in dst_vertices based on QHull's vertex ID.
Vec3i indices;
int cnt = 0;
for (const orgQhull::QhullVertex vertex : facet.vertices()) {
int id = vertex.id();
assert(id >= 0);
if (id >= int(map_dst_vertices.size()))
map_dst_vertices.resize(next_highest_power_of_2(size_t(id + 1)), -1);
if (int i = map_dst_vertices[id]; i == -1) {
// Allocate a new vertex.
i = int(dst_vertices.size());
map_dst_vertices[id] = i;
orgQhull::QhullPoint pt(vertex.point());
dst_vertices.emplace_back(pt[0], pt[1], pt[2]);
indices[cnt] = i;
} else {
// Reuse existing vertex.
indices[cnt] = i;
}
if (cnt ++ == 3)
break;
}
assert(cnt == 3);
if (cnt == 3) {
// QHull sorts vertices of a face lexicographically by their IDs, not by face normals.
// Calculate face normal based on the order of vertices.
Vec3f n = (dst_vertices[indices(1)] - dst_vertices[indices(0)]).cross(dst_vertices[indices(2)] - dst_vertices[indices(1)]);
auto *n2 = facet.getBaseT()->normal;
auto d = n.x() * n2[0] + n.y() * n2[1] + n.z() * n2[2];
#ifndef NDEBUG
Vec3f n3 = (dst_vertices[indices(0)] - centroid);
auto d3 = n.dot(n3);
assert((d < 0.f) == (d3 < 0.f));
#endif // NDEBUG
// Get the face normal from QHull.
if (d < 0.f)
// Fix face orientation.
std::swap(indices[1], indices[2]);
dst_facets.emplace_back(indices);
}
}
}
return { std::move(dst_facets), std::move(dst_vertices) };
}
void its_reverse_all_facets(indexed_triangle_set &its)
{
for (stl_triangle_vertex_indices &face : its.indices)
std::swap(face[0], face[1]);
}
void its_merge(indexed_triangle_set &A, const indexed_triangle_set &B)
{
auto N = int(A.vertices.size());
auto N_f = A.indices.size();
A.vertices.insert(A.vertices.end(), B.vertices.begin(), B.vertices.end());
A.indices.insert(A.indices.end(), B.indices.begin(), B.indices.end());
for(size_t n = N_f; n < A.indices.size(); n++)
A.indices[n] += Vec3i{N, N, N};
}
void its_merge(indexed_triangle_set &A, const std::vector<Vec3f> &triangles)
{
const size_t offs = A.vertices.size();
A.vertices.insert(A.vertices.end(), triangles.begin(), triangles.end());
A.indices.reserve(A.indices.size() + A.vertices.size() / 3);
for(int i = int(offs); i < int(A.vertices.size()); i += 3)
A.indices.emplace_back(i, i + 1, i + 2);
}
void its_merge(indexed_triangle_set &A, const Pointf3s &triangles)
{
auto trianglesf = reserve_vector<Vec3f> (triangles.size());
for (auto &t : triangles)
trianglesf.emplace_back(t.cast<float>());
its_merge(A, trianglesf);
}
float its_volume(const indexed_triangle_set &its)
{
if (its.empty()) return 0.;
// Choose a point, any point as the reference.
auto p0 = its.vertices.front();
float volume = 0.f;
for (size_t i = 0; i < its.indices.size(); ++ i) {
// Do dot product to get distance from point to plane.
its_triangle triangle = its_triangle_vertices(its, i);
Vec3f U = triangle[1] - triangle[0];
Vec3f V = triangle[2] - triangle[0];
Vec3f C = U.cross(V);
Vec3f normal = C.normalized();
float area = 0.5 * C.norm();
float height = normal.dot(triangle[0] - p0);
volume += (area * height) / 3.0f;
}
return volume;
}
float its_average_edge_length(const indexed_triangle_set &its)
{
if (its.indices.empty())
return 0.f;
double edge_length = 0.f;
for (size_t i = 0; i < its.indices.size(); ++ i) {
const its_triangle v = its_triangle_vertices(its, i);
edge_length += (v[1] - v[0]).cast<double>().norm() +
(v[2] - v[0]).cast<double>().norm() +
(v[1] - v[2]).cast<double>().norm();
}
return float(edge_length / (3 * its.indices.size()));
}
std::vector<indexed_triangle_set> its_split(const indexed_triangle_set &its)
{
return its_split<>(its);
}
// Number of disconnected patches (faces are connected if they share an edge, shared edge defined with 2 shared vertex indices).
size_t its_number_of_patches(const indexed_triangle_set &its)
{
return its_number_of_patches<>(its);
}
size_t its_number_of_patches(const indexed_triangle_set &its, const std::vector<Vec3i> &face_neighbors)
{
return its_number_of_patches<>(ItsNeighborsWrapper{ its, face_neighbors });
}
// Same as its_number_of_patches(its) > 1, but faster.
bool its_is_splittable(const indexed_triangle_set &its)
{
return its_is_splittable<>(its);
}
bool its_is_splittable(const indexed_triangle_set &its, const std::vector<Vec3i> &face_neighbors)
{
return its_is_splittable<>(ItsNeighborsWrapper{ its, face_neighbors });
}
size_t its_num_open_edges(const std::vector<Vec3i> &face_neighbors)
{
size_t num_open_edges = 0;
for (Vec3i neighbors : face_neighbors)
for (int n : neighbors)
if (n < 0)
++ num_open_edges;
return num_open_edges;
}
size_t its_num_open_edges(const indexed_triangle_set &its)
{
return its_num_open_edges(its_face_neighbors(its));
}
void VertexFaceIndex::create(const indexed_triangle_set &its)
{
m_vertex_to_face_start.assign(its.vertices.size() + 1, 0);
// 1) Calculate vertex incidence by scatter.
for (auto &face : its.indices) {
++ m_vertex_to_face_start[face(0) + 1];
++ m_vertex_to_face_start[face(1) + 1];
++ m_vertex_to_face_start[face(2) + 1];
}
// 2) Prefix sum to calculate offsets to m_vertex_faces_all.
for (size_t i = 2; i < m_vertex_to_face_start.size(); ++ i)
m_vertex_to_face_start[i] += m_vertex_to_face_start[i - 1];
// 3) Scatter indices of faces incident to a vertex into m_vertex_faces_all.
m_vertex_faces_all.assign(m_vertex_to_face_start.back(), 0);
for (size_t face_idx = 0; face_idx < its.indices.size(); ++ face_idx) {
auto &face = its.indices[face_idx];
for (int i = 0; i < 3; ++ i)
m_vertex_faces_all[m_vertex_to_face_start[face(i)] ++] = face_idx;
}
// 4) The previous loop modified m_vertex_to_face_start. Revert the change.
for (auto i = int(m_vertex_to_face_start.size()) - 1; i > 0; -- i)
m_vertex_to_face_start[i] = m_vertex_to_face_start[i - 1];
m_vertex_to_face_start.front() = 0;
}
std::vector<Vec3i> its_face_neighbors(const indexed_triangle_set &its)
{
return create_face_neighbors_index(ex_seq, its);
}
std::vector<Vec3i> its_face_neighbors_par(const indexed_triangle_set &its)
{
return create_face_neighbors_index(ex_tbb, its);
}
std::vector<Vec3f> its_face_normals(const indexed_triangle_set &its)
{
std::vector<Vec3f> normals;
normals.reserve(its.indices.size());
for (stl_triangle_vertex_indices face : its.indices)
normals.push_back(its_face_normal(its, face));
return normals;
}
#if BOOST_ENDIAN_LITTLE_BYTE
static inline void big_endian_reverse_quads(char*, size_t) {}
#else // BOOST_ENDIAN_LITTLE_BYTE
static inline void big_endian_reverse_quads(char *buf, size_t cnt)
{
for (size_t i = 0; i < cnt; i += 4) {
std::swap(buf[i], buf[i+3]);
std::swap(buf[i+1], buf[i+2]);
}
}
#endif // BOOST_ENDIAN_LITTLE_BYTE
bool its_write_stl_ascii(const char *file, const char *label, const std::vector<stl_triangle_vertex_indices> &indices, const std::vector<stl_vertex> &vertices)
{
FILE *fp = boost::nowide::fopen(file, "w");
if (fp == nullptr) {
BOOST_LOG_TRIVIAL(error) << "its_write_stl_ascii: Couldn't open " << file << " for writing";
return false;
}
fprintf(fp, "solid %s\n", label);
for (const stl_triangle_vertex_indices& face : indices) {
Vec3f vertex[3] = { vertices[face(0)], vertices[face(1)], vertices[face(2)] };
Vec3f normal = (vertex[1] - vertex[0]).cross(vertex[2] - vertex[1]).normalized();
fprintf(fp, " facet normal % .8E % .8E % .8E\n", normal(0), normal(1), normal(2));
fprintf(fp, " outer loop\n");
fprintf(fp, " vertex % .8E % .8E % .8E\n", vertex[0](0), vertex[0](1), vertex[0](2));
fprintf(fp, " vertex % .8E % .8E % .8E\n", vertex[1](0), vertex[1](1), vertex[1](2));
fprintf(fp, " vertex % .8E % .8E % .8E\n", vertex[2](0), vertex[2](1), vertex[2](2));
fprintf(fp, " endloop\n");
fprintf(fp, " endfacet\n");
}
fprintf(fp, "endsolid %s\n", label);
fclose(fp);
return true;
}
bool its_write_stl_binary(const char *file, const char *label, const std::vector<stl_triangle_vertex_indices> &indices, const std::vector<stl_vertex> &vertices)
{
FILE *fp = boost::nowide::fopen(file, "wb");
if (fp == nullptr) {
BOOST_LOG_TRIVIAL(error) << "its_write_stl_binary: Couldn't open " << file << " for writing";
return false;
}
{
static constexpr const int header_size = 80;
std::vector<char> header(header_size, 0);
if (int header_len = std::min((label == nullptr) ? 0 : int(strlen(label)), header_size); header_len > 0)
::memcpy(header.data(), label, header_len);
::fwrite(header.data(), header_size, 1, fp);
}
uint32_t nfaces = indices.size();
big_endian_reverse_quads(reinterpret_cast<char*>(&nfaces), 4);
::fwrite(&nfaces, 4, 1, fp);
stl_facet f;
f.extra[0] = 0;
f.extra[1] = 0;
for (const stl_triangle_vertex_indices& face : indices) {
f.vertex[0] = vertices[face(0)];
f.vertex[1] = vertices[face(1)];
f.vertex[2] = vertices[face(2)];
f.normal = (f.vertex[1] - f.vertex[0]).cross(f.vertex[2] - f.vertex[1]).normalized();
big_endian_reverse_quads(reinterpret_cast<char*>(&f), 48);
fwrite(&f, 50, 1, fp);
}
fclose(fp);
return true;
}
} // namespace Slic3r