PrusaSlicer-NonPlainar/xs/src/libslic3r/TriangleMesh.cpp
2017-02-21 16:10:38 +01:00

1202 lines
44 KiB
C++

#include "TriangleMesh.hpp"
#include "ClipperUtils.hpp"
#include "Geometry.hpp"
#include <cmath>
#include <deque>
#include <queue>
#include <set>
#include <vector>
#include <map>
#include <utility>
#include <algorithm>
#include <math.h>
#include <assert.h>
#ifdef SLIC3R_DEBUG
// #define SLIC3R_TRIANGLEMESH_DEBUG
#include "SVG.hpp"
#endif
namespace Slic3r {
TriangleMesh::TriangleMesh()
: repaired(false)
{
stl_initialize(&this->stl);
}
TriangleMesh::TriangleMesh(const Pointf3s &points, const std::vector<Point3>& facets )
: repaired(false)
{
stl_initialize(&this->stl);
stl_file &stl = this->stl;
stl.error = 0;
stl.stats.type = inmemory;
// count facets and allocate memory
stl.stats.number_of_facets = facets.size();
stl.stats.original_num_facets = stl.stats.number_of_facets;
stl_allocate(&stl);
for (int i = 0; i < stl.stats.number_of_facets; i++) {
stl_facet facet;
facet.normal.x = 0;
facet.normal.y = 0;
facet.normal.z = 0;
const Pointf3& ref_f1 = points[facets[i].x];
facet.vertex[0].x = ref_f1.x;
facet.vertex[0].y = ref_f1.y;
facet.vertex[0].z = ref_f1.z;
const Pointf3& ref_f2 = points[facets[i].y];
facet.vertex[1].x = ref_f2.x;
facet.vertex[1].y = ref_f2.y;
facet.vertex[1].z = ref_f2.z;
const Pointf3& ref_f3 = points[facets[i].z];
facet.vertex[2].x = ref_f3.x;
facet.vertex[2].y = ref_f3.y;
facet.vertex[2].z = ref_f3.z;
facet.extra[0] = 0;
facet.extra[1] = 0;
stl.facet_start[i] = facet;
}
stl_get_size(&stl);
}
TriangleMesh::TriangleMesh(const TriangleMesh &other)
: stl(other.stl), repaired(other.repaired)
{
this->stl.heads = NULL;
this->stl.tail = NULL;
this->stl.error = other.stl.error;
if (other.stl.facet_start != NULL) {
this->stl.facet_start = (stl_facet*)calloc(other.stl.stats.number_of_facets, sizeof(stl_facet));
std::copy(other.stl.facet_start, other.stl.facet_start + other.stl.stats.number_of_facets, this->stl.facet_start);
}
if (other.stl.neighbors_start != NULL) {
this->stl.neighbors_start = (stl_neighbors*)calloc(other.stl.stats.number_of_facets, sizeof(stl_neighbors));
std::copy(other.stl.neighbors_start, other.stl.neighbors_start + other.stl.stats.number_of_facets, this->stl.neighbors_start);
}
if (other.stl.v_indices != NULL) {
this->stl.v_indices = (v_indices_struct*)calloc(other.stl.stats.number_of_facets, sizeof(v_indices_struct));
std::copy(other.stl.v_indices, other.stl.v_indices + other.stl.stats.number_of_facets, this->stl.v_indices);
}
if (other.stl.v_shared != NULL) {
this->stl.v_shared = (stl_vertex*)calloc(other.stl.stats.shared_vertices, sizeof(stl_vertex));
std::copy(other.stl.v_shared, other.stl.v_shared + other.stl.stats.shared_vertices, this->stl.v_shared);
}
}
TriangleMesh& TriangleMesh::operator= (TriangleMesh other)
{
this->swap(other);
return *this;
}
void
TriangleMesh::swap(TriangleMesh &other)
{
std::swap(this->stl, other.stl);
std::swap(this->repaired, other.repaired);
}
TriangleMesh::~TriangleMesh() {
stl_close(&this->stl);
}
void
TriangleMesh::ReadSTLFile(char* input_file) {
stl_open(&stl, input_file);
}
void
TriangleMesh::write_ascii(char* output_file)
{
stl_write_ascii(&this->stl, output_file, "");
}
void
TriangleMesh::write_binary(char* output_file)
{
stl_write_binary(&this->stl, output_file, "");
}
void
TriangleMesh::repair() {
if (this->repaired) return;
// admesh fails when repairing empty meshes
if (this->stl.stats.number_of_facets == 0) return;
// checking exact
stl_check_facets_exact(&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 = stl.stats.shortest_edge;
float increment = stl.stats.bounding_diameter / 10000.0;
int iterations = 2;
if (stl.stats.connected_facets_3_edge < stl.stats.number_of_facets) {
for (int i = 0; i < iterations; i++) {
if (stl.stats.connected_facets_3_edge < stl.stats.number_of_facets) {
//printf("Checking nearby. Tolerance= %f Iteration=%d of %d...", tolerance, i + 1, iterations);
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;
}
}
}
// remove_unconnected
if (stl.stats.connected_facets_3_edge < stl.stats.number_of_facets) {
stl_remove_unconnected_facets(&stl);
}
// fill_holes
if (stl.stats.connected_facets_3_edge < stl.stats.number_of_facets) {
stl_fill_holes(&stl);
stl_clear_error(&stl);
}
// normal_directions
stl_fix_normal_directions(&stl);
// normal_values
stl_fix_normal_values(&stl);
// always calculate the volume and reverse all normals if volume is negative
stl_calculate_volume(&stl);
// neighbors
stl_verify_neighbors(&stl);
this->repaired = true;
}
void
TriangleMesh::reset_repair_stats() {
this->stl.stats.degenerate_facets = 0;
this->stl.stats.edges_fixed = 0;
this->stl.stats.facets_removed = 0;
this->stl.stats.facets_added = 0;
this->stl.stats.facets_reversed = 0;
this->stl.stats.backwards_edges = 0;
this->stl.stats.normals_fixed = 0;
}
bool
TriangleMesh::needed_repair() const
{
return this->stl.stats.degenerate_facets > 0
|| this->stl.stats.edges_fixed > 0
|| this->stl.stats.facets_removed > 0
|| this->stl.stats.facets_added > 0
|| this->stl.stats.facets_reversed > 0
|| this->stl.stats.backwards_edges > 0;
}
size_t
TriangleMesh::facets_count() const
{
return this->stl.stats.number_of_facets;
}
void
TriangleMesh::WriteOBJFile(char* output_file) {
stl_generate_shared_vertices(&stl);
stl_write_obj(&stl, output_file);
}
void TriangleMesh::scale(float factor)
{
stl_scale(&(this->stl), factor);
stl_invalidate_shared_vertices(&this->stl);
}
void TriangleMesh::scale(const Pointf3 &versor)
{
float fversor[3];
fversor[0] = versor.x;
fversor[1] = versor.y;
fversor[2] = versor.z;
stl_scale_versor(&this->stl, fversor);
stl_invalidate_shared_vertices(&this->stl);
}
void TriangleMesh::translate(float x, float y, float z)
{
if (x == 0.f && y == 0.f && z == 0.f)
return;
stl_translate_relative(&(this->stl), x, y, z);
stl_invalidate_shared_vertices(&this->stl);
}
void TriangleMesh::rotate(float angle, const Axis &axis)
{
if (angle == 0.f)
return;
// admesh uses degrees
angle = Slic3r::Geometry::rad2deg(angle);
if (axis == X) {
stl_rotate_x(&(this->stl), angle);
} else if (axis == Y) {
stl_rotate_y(&(this->stl), angle);
} else if (axis == Z) {
stl_rotate_z(&(this->stl), angle);
}
stl_invalidate_shared_vertices(&this->stl);
}
void TriangleMesh::rotate_x(float angle)
{
this->rotate(angle, X);
}
void TriangleMesh::rotate_y(float angle)
{
this->rotate(angle, Y);
}
void TriangleMesh::rotate_z(float angle)
{
this->rotate(angle, Z);
}
void TriangleMesh::mirror(const Axis &axis)
{
if (axis == X) {
stl_mirror_yz(&this->stl);
} else if (axis == Y) {
stl_mirror_xz(&this->stl);
} else if (axis == Z) {
stl_mirror_xy(&this->stl);
}
stl_invalidate_shared_vertices(&this->stl);
}
void TriangleMesh::mirror_x()
{
this->mirror(X);
}
void TriangleMesh::mirror_y()
{
this->mirror(Y);
}
void TriangleMesh::mirror_z()
{
this->mirror(Z);
}
void TriangleMesh::align_to_origin()
{
this->translate(
-(this->stl.stats.min.x),
-(this->stl.stats.min.y),
-(this->stl.stats.min.z)
);
}
void TriangleMesh::rotate(double angle, Point* center)
{
if (angle == 0.)
return;
this->translate(-center->x, -center->y, 0);
stl_rotate_z(&(this->stl), (float)angle);
this->translate(+center->x, +center->y, 0);
}
TriangleMeshPtrs
TriangleMesh::split() const
{
TriangleMeshPtrs meshes;
std::set<int> seen_facets;
// we need neighbors
if (!this->repaired) CONFESS("split() requires repair()");
// loop while we have remaining facets
while (1) {
// get the first facet
std::queue<int> facet_queue;
std::deque<int> facets;
for (int facet_idx = 0; facet_idx < this->stl.stats.number_of_facets; facet_idx++) {
if (seen_facets.find(facet_idx) == seen_facets.end()) {
// if facet was not seen put it into queue and start searching
facet_queue.push(facet_idx);
break;
}
}
if (facet_queue.empty()) break;
while (!facet_queue.empty()) {
int facet_idx = facet_queue.front();
facet_queue.pop();
if (seen_facets.find(facet_idx) != seen_facets.end()) continue;
facets.push_back(facet_idx);
for (int j = 0; j <= 2; j++) {
facet_queue.push(this->stl.neighbors_start[facet_idx].neighbor[j]);
}
seen_facets.insert(facet_idx);
}
TriangleMesh* mesh = new TriangleMesh;
meshes.push_back(mesh);
mesh->stl.stats.type = inmemory;
mesh->stl.stats.number_of_facets = facets.size();
mesh->stl.stats.original_num_facets = mesh->stl.stats.number_of_facets;
stl_clear_error(&mesh->stl);
stl_allocate(&mesh->stl);
int first = 1;
for (std::deque<int>::const_iterator facet = facets.begin(); facet != facets.end(); ++facet) {
mesh->stl.facet_start[facet - facets.begin()] = this->stl.facet_start[*facet];
stl_facet_stats(&mesh->stl, this->stl.facet_start[*facet], first);
first = 0;
}
}
return meshes;
}
void
TriangleMesh::merge(const TriangleMesh &mesh)
{
// reset stats and metadata
int number_of_facets = this->stl.stats.number_of_facets;
stl_invalidate_shared_vertices(&this->stl);
this->repaired = false;
// update facet count and allocate more memory
this->stl.stats.number_of_facets = number_of_facets + mesh.stl.stats.number_of_facets;
this->stl.stats.original_num_facets = this->stl.stats.number_of_facets;
stl_reallocate(&this->stl);
// copy facets
for (int i = 0; i < mesh.stl.stats.number_of_facets; i++) {
this->stl.facet_start[number_of_facets + i] = mesh.stl.facet_start[i];
}
// update size
stl_get_size(&this->stl);
}
/* this will return scaled ExPolygons */
ExPolygons
TriangleMesh::horizontal_projection() const
{
Polygons pp;
pp.reserve(this->stl.stats.number_of_facets);
for (int i = 0; i < this->stl.stats.number_of_facets; i++) {
stl_facet* facet = &this->stl.facet_start[i];
Polygon p;
p.points.resize(3);
p.points[0] = Point(facet->vertex[0].x / SCALING_FACTOR, facet->vertex[0].y / SCALING_FACTOR);
p.points[1] = Point(facet->vertex[1].x / SCALING_FACTOR, facet->vertex[1].y / SCALING_FACTOR);
p.points[2] = Point(facet->vertex[2].x / SCALING_FACTOR, facet->vertex[2].y / SCALING_FACTOR);
p.make_counter_clockwise(); // do this after scaling, as winding order might change while doing that
pp.push_back(p);
}
// the offset factor was tuned using groovemount.stl
return union_ex(offset(pp, 0.01 / SCALING_FACTOR), true);
}
Polygon
TriangleMesh::convex_hull()
{
this->require_shared_vertices();
Points pp;
pp.reserve(this->stl.stats.shared_vertices);
for (int i = 0; i < this->stl.stats.shared_vertices; i++) {
stl_vertex* v = &this->stl.v_shared[i];
pp.push_back(Point(v->x / SCALING_FACTOR, v->y / SCALING_FACTOR));
}
return Slic3r::Geometry::convex_hull(pp);
}
BoundingBoxf3
TriangleMesh::bounding_box() const
{
BoundingBoxf3 bb;
bb.min.x = this->stl.stats.min.x;
bb.min.y = this->stl.stats.min.y;
bb.min.z = this->stl.stats.min.z;
bb.max.x = this->stl.stats.max.x;
bb.max.y = this->stl.stats.max.y;
bb.max.z = this->stl.stats.max.z;
return bb;
}
void
TriangleMesh::require_shared_vertices()
{
if (!this->repaired) this->repair();
if (this->stl.v_shared == NULL) stl_generate_shared_vertices(&(this->stl));
}
void
TriangleMeshSlicer::slice(const std::vector<float> &z, std::vector<Polygons>* layers) const
{
/*
This method gets called with a list of unscaled Z coordinates and outputs
a vector pointer having the same number of items as the original list.
Each item is a vector of polygons created by slicing our mesh at the
given heights.
This method should basically combine the behavior of the existing
Perl methods defined in lib/Slic3r/TriangleMesh.pm:
- analyze(): this creates the 'facets_edges' and the 'edges_facets'
tables (we don't need the 'edges' table)
- slice_facet(): this has to be done for each facet. It generates
intersection lines with each plane identified by the Z list.
The get_layer_range() binary search used to identify the Z range
of the facet is already ported to C++ (see Object.xsp)
- make_loops(): this has to be done for each layer. It creates polygons
from the lines generated by the previous step.
At the end, we free the tables generated by analyze() as we don't
need them anymore.
NOTE: this method accepts a vector of floats because the mesh coordinate
type is float.
*/
std::vector<IntersectionLines> lines(z.size());
{
boost::mutex lines_mutex;
parallelize<int>(
0,
this->mesh->stl.stats.number_of_facets-1,
boost::bind(&TriangleMeshSlicer::_slice_do, this, _1, &lines, &lines_mutex, z)
);
}
// v_scaled_shared could be freed here
// build loops
layers->resize(z.size());
parallelize<size_t>(
0,
lines.size()-1,
boost::bind(&TriangleMeshSlicer::_make_loops_do, this, _1, &lines, layers)
);
}
void
TriangleMeshSlicer::_slice_do(size_t facet_idx, std::vector<IntersectionLines>* lines, boost::mutex* lines_mutex,
const std::vector<float> &z) const
{
const stl_facet &facet = this->mesh->stl.facet_start[facet_idx];
// find facet extents
const float min_z = fminf(facet.vertex[0].z, fminf(facet.vertex[1].z, facet.vertex[2].z));
const float max_z = fmaxf(facet.vertex[0].z, fmaxf(facet.vertex[1].z, facet.vertex[2].z));
#ifdef SLIC3R_DEBUG
printf("\n==> FACET %d (%f,%f,%f - %f,%f,%f - %f,%f,%f):\n", facet_idx,
facet.vertex[0].x, facet.vertex[0].y, facet.vertex[0].z,
facet.vertex[1].x, facet.vertex[1].y, facet.vertex[1].z,
facet.vertex[2].x, facet.vertex[2].y, facet.vertex[2].z);
printf("z: min = %.2f, max = %.2f\n", min_z, max_z);
#endif
// find layer extents
std::vector<float>::const_iterator min_layer, max_layer;
min_layer = std::lower_bound(z.begin(), z.end(), min_z); // first layer whose slice_z is >= min_z
max_layer = std::upper_bound(z.begin() + (min_layer - z.begin()), z.end(), max_z) - 1; // last layer whose slice_z is <= max_z
#ifdef SLIC3R_DEBUG
printf("layers: min = %d, max = %d\n", (int)(min_layer - z.begin()), (int)(max_layer - z.begin()));
#endif
for (std::vector<float>::const_iterator it = min_layer; it != max_layer + 1; ++it) {
std::vector<float>::size_type layer_idx = it - z.begin();
this->slice_facet(*it / SCALING_FACTOR, facet, facet_idx, min_z, max_z, &(*lines)[layer_idx], lines_mutex);
}
}
void
TriangleMeshSlicer::slice(const std::vector<float> &z, std::vector<ExPolygons>* layers) const
{
std::vector<Polygons> layers_p;
this->slice(z, &layers_p);
layers->resize(z.size());
for (std::vector<Polygons>::const_iterator loops = layers_p.begin(); loops != layers_p.end(); ++loops) {
#ifdef SLIC3R_TRIANGLEMESH_DEBUG
size_t layer_id = loops - layers_p.begin();
printf("Layer " PRINTF_ZU " (slice_z = %.2f):\n", layer_id, z[layer_id]);
#endif
this->make_expolygons(*loops, &(*layers)[ loops - layers_p.begin() ]);
}
}
void
TriangleMeshSlicer::slice_facet(float slice_z, const stl_facet &facet, const int &facet_idx,
const float &min_z, const float &max_z, std::vector<IntersectionLine>* lines,
boost::mutex* lines_mutex) const
{
std::vector<IntersectionPoint> points;
std::vector< std::vector<IntersectionPoint>::size_type > points_on_layer;
bool found_horizontal_edge = false;
/* reorder vertices so that the first one is the one with lowest Z
this is needed to get all intersection lines in a consistent order
(external on the right of the line) */
int i = 0;
if (facet.vertex[1].z == min_z) {
// vertex 1 has lowest Z
i = 1;
} else if (facet.vertex[2].z == min_z) {
// vertex 2 has lowest Z
i = 2;
}
for (int j = i; (j-i) < 3; j++) { // loop through facet edges
int edge_id = this->facets_edges[facet_idx][j % 3];
int a_id = this->mesh->stl.v_indices[facet_idx].vertex[j % 3];
int b_id = this->mesh->stl.v_indices[facet_idx].vertex[(j+1) % 3];
stl_vertex* a = &this->v_scaled_shared[a_id];
stl_vertex* b = &this->v_scaled_shared[b_id];
if (a->z == b->z && a->z == slice_z) {
// edge is horizontal and belongs to the current layer
stl_vertex &v0 = this->v_scaled_shared[ this->mesh->stl.v_indices[facet_idx].vertex[0] ];
stl_vertex &v1 = this->v_scaled_shared[ this->mesh->stl.v_indices[facet_idx].vertex[1] ];
stl_vertex &v2 = this->v_scaled_shared[ this->mesh->stl.v_indices[facet_idx].vertex[2] ];
IntersectionLine line;
if (min_z == max_z) {
line.edge_type = feHorizontal;
if (this->mesh->stl.facet_start[facet_idx].normal.z < 0) {
/* if normal points downwards this is a bottom horizontal facet so we reverse
its point order */
std::swap(a, b);
std::swap(a_id, b_id);
}
} else if (v0.z < slice_z || v1.z < slice_z || v2.z < slice_z) {
line.edge_type = feTop;
std::swap(a, b);
std::swap(a_id, b_id);
} else {
line.edge_type = feBottom;
}
line.a.x = a->x;
line.a.y = a->y;
line.b.x = b->x;
line.b.y = b->y;
line.a_id = a_id;
line.b_id = b_id;
if (lines_mutex != NULL) {
boost::lock_guard<boost::mutex> l(*lines_mutex);
lines->push_back(line);
} else {
lines->push_back(line);
}
found_horizontal_edge = true;
// if this is a top or bottom edge, we can stop looping through edges
// because we won't find anything interesting
if (line.edge_type != feHorizontal) return;
} else if (a->z == slice_z) {
IntersectionPoint point;
point.x = a->x;
point.y = a->y;
point.point_id = a_id;
points.push_back(point);
points_on_layer.push_back(points.size()-1);
} else if (b->z == slice_z) {
IntersectionPoint point;
point.x = b->x;
point.y = b->y;
point.point_id = b_id;
points.push_back(point);
points_on_layer.push_back(points.size()-1);
} else if ((a->z < slice_z && b->z > slice_z) || (b->z < slice_z && a->z > slice_z)) {
// edge intersects the current layer; calculate intersection
IntersectionPoint point;
point.x = b->x + (a->x - b->x) * (slice_z - b->z) / (a->z - b->z);
point.y = b->y + (a->y - b->y) * (slice_z - b->z) / (a->z - b->z);
point.edge_id = edge_id;
points.push_back(point);
}
}
if (found_horizontal_edge) return;
if (!points_on_layer.empty()) {
// we can't have only one point on layer because each vertex gets detected
// twice (once for each edge), and we can't have three points on layer because
// we assume this code is not getting called for horizontal facets
assert(points_on_layer.size() == 2);
assert( points[ points_on_layer[0] ].point_id == points[ points_on_layer[1] ].point_id );
if (points.size() < 3) return; // no intersection point, this is a V-shaped facet tangent to plane
points.erase( points.begin() + points_on_layer[1] );
}
if (!points.empty()) {
assert(points.size() == 2); // facets must intersect each plane 0 or 2 times
IntersectionLine line;
line.a = (Point)points[1];
line.b = (Point)points[0];
line.a_id = points[1].point_id;
line.b_id = points[0].point_id;
line.edge_a_id = points[1].edge_id;
line.edge_b_id = points[0].edge_id;
if (lines_mutex != NULL) {
boost::lock_guard<boost::mutex> l(*lines_mutex);
lines->push_back(line);
} else {
lines->push_back(line);
}
return;
}
}
void
TriangleMeshSlicer::_make_loops_do(size_t i, std::vector<IntersectionLines>* lines, std::vector<Polygons>* layers) const
{
this->make_loops((*lines)[i], &(*layers)[i]);
}
void
TriangleMeshSlicer::make_loops(std::vector<IntersectionLine> &lines, Polygons* loops) const
{
/*
SVG svg("lines.svg");
svg.draw(lines);
svg.Close();
*/
// remove tangent edges
for (IntersectionLines::iterator line = lines.begin(); line != lines.end(); ++line) {
if (line->skip || line->edge_type == feNone) continue;
/* if the line is a facet edge, find another facet edge
having the same endpoints but in reverse order */
for (IntersectionLines::iterator line2 = line + 1; line2 != lines.end(); ++line2) {
if (line2->skip || line2->edge_type == feNone) continue;
// are these facets adjacent? (sharing a common edge on this layer)
if (line->a_id == line2->a_id && line->b_id == line2->b_id) {
line2->skip = true;
/* if they are both oriented upwards or downwards (like a 'V')
then we can remove both edges from this layer since it won't
affect the sliced shape */
/* if one of them is oriented upwards and the other is oriented
downwards, let's only keep one of them (it doesn't matter which
one since all 'top' lines were reversed at slicing) */
if (line->edge_type == line2->edge_type) {
line->skip = true;
break;
}
} else if (line->a_id == line2->b_id && line->b_id == line2->a_id) {
/* if this edge joins two horizontal facets, remove both of them */
if (line->edge_type == feHorizontal && line2->edge_type == feHorizontal) {
line->skip = true;
line2->skip = true;
break;
}
}
}
}
// build a map of lines by edge_a_id and a_id
std::vector<IntersectionLinePtrs> by_edge_a_id, by_a_id;
by_edge_a_id.resize(this->mesh->stl.stats.number_of_facets * 3);
by_a_id.resize(this->mesh->stl.stats.shared_vertices);
for (IntersectionLines::iterator line = lines.begin(); line != lines.end(); ++line) {
if (line->skip) continue;
if (line->edge_a_id != -1) by_edge_a_id[line->edge_a_id].push_back(&(*line));
if (line->a_id != -1) by_a_id[line->a_id].push_back(&(*line));
}
CYCLE: while (1) {
// take first spare line and start a new loop
IntersectionLine* first_line = NULL;
for (IntersectionLines::iterator line = lines.begin(); line != lines.end(); ++line) {
if (line->skip) continue;
first_line = &(*line);
break;
}
if (first_line == NULL) break;
first_line->skip = true;
IntersectionLinePtrs loop;
loop.push_back(first_line);
/*
printf("first_line edge_a_id = %d, edge_b_id = %d, a_id = %d, b_id = %d, a = %d,%d, b = %d,%d\n",
first_line->edge_a_id, first_line->edge_b_id, first_line->a_id, first_line->b_id,
first_line->a.x, first_line->a.y, first_line->b.x, first_line->b.y);
*/
while (1) {
// find a line starting where last one finishes
IntersectionLine* next_line = NULL;
if (loop.back()->edge_b_id != -1) {
IntersectionLinePtrs &candidates = by_edge_a_id[loop.back()->edge_b_id];
for (IntersectionLinePtrs::iterator lineptr = candidates.begin(); lineptr != candidates.end(); ++lineptr) {
if ((*lineptr)->skip) continue;
next_line = *lineptr;
break;
}
}
if (next_line == NULL && loop.back()->b_id != -1) {
IntersectionLinePtrs &candidates = by_a_id[loop.back()->b_id];
for (IntersectionLinePtrs::iterator lineptr = candidates.begin(); lineptr != candidates.end(); ++lineptr) {
if ((*lineptr)->skip) continue;
next_line = *lineptr;
break;
}
}
if (next_line == NULL) {
// check whether we closed this loop
if ((loop.front()->edge_a_id != -1 && loop.front()->edge_a_id == loop.back()->edge_b_id)
|| (loop.front()->a_id != -1 && loop.front()->a_id == loop.back()->b_id)) {
// loop is complete
Polygon p;
p.points.reserve(loop.size());
for (IntersectionLinePtrs::const_iterator lineptr = loop.begin(); lineptr != loop.end(); ++lineptr) {
p.points.push_back((*lineptr)->a);
}
loops->push_back(p);
#ifdef SLIC3R_TRIANGLEMESH_DEBUG
printf(" Discovered %s polygon of %d points\n", (p.is_counter_clockwise() ? "ccw" : "cw"), (int)p.points.size());
#endif
goto CYCLE;
}
// we can't close this loop!
//// push @failed_loops, [@loop];
//#ifdef SLIC3R_TRIANGLEMESH_DEBUG
printf(" Unable to close this loop having %d points\n", (int)loop.size());
//#endif
goto CYCLE;
}
/*
printf("next_line edge_a_id = %d, edge_b_id = %d, a_id = %d, b_id = %d, a = %d,%d, b = %d,%d\n",
next_line->edge_a_id, next_line->edge_b_id, next_line->a_id, next_line->b_id,
next_line->a.x, next_line->a.y, next_line->b.x, next_line->b.y);
*/
loop.push_back(next_line);
next_line->skip = true;
}
}
}
class _area_comp {
public:
_area_comp(std::vector<double>* _aa) : abs_area(_aa) {};
bool operator() (const size_t &a, const size_t &b) {
return (*this->abs_area)[a] > (*this->abs_area)[b];
}
private:
std::vector<double>* abs_area;
};
void
TriangleMeshSlicer::make_expolygons_simple(std::vector<IntersectionLine> &lines, ExPolygons* slices) const
{
Polygons loops;
this->make_loops(lines, &loops);
Polygons cw;
for (Polygons::const_iterator loop = loops.begin(); loop != loops.end(); ++loop) {
if (loop->area() >= 0) {
ExPolygon ex;
ex.contour = *loop;
slices->push_back(ex);
} else {
cw.push_back(*loop);
}
}
// assign holes to contours
for (Polygons::const_iterator loop = cw.begin(); loop != cw.end(); ++loop) {
int slice_idx = -1;
double current_contour_area = -1;
for (ExPolygons::iterator slice = slices->begin(); slice != slices->end(); ++slice) {
if (slice->contour.contains(loop->points.front())) {
double area = slice->contour.area();
if (area < current_contour_area || current_contour_area == -1) {
slice_idx = slice - slices->begin();
current_contour_area = area;
}
}
}
(*slices)[slice_idx].holes.push_back(*loop);
}
}
void
TriangleMeshSlicer::make_expolygons(const Polygons &loops, ExPolygons* slices) const
{
/*
Input loops are not suitable for evenodd nor nonzero fill types, as we might get
two consecutive concentric loops having the same winding order - and we have to
respect such order. In that case, evenodd would create wrong inversions, and nonzero
would ignore holes inside two concentric contours.
So we're ordering loops and collapse consecutive concentric loops having the same
winding order.
TODO: find a faster algorithm for this, maybe with some sort of binary search.
If we computed a "nesting tree" we could also just remove the consecutive loops
having the same winding order, and remove the extra one(s) so that we could just
supply everything to offset() instead of performing several union/diff calls.
we sort by area assuming that the outermost loops have larger area;
the previous sorting method, based on $b->contains($a->[0]), failed to nest
loops correctly in some edge cases when original model had overlapping facets
*/
std::vector<double> area;
std::vector<double> abs_area;
std::vector<size_t> sorted_area; // vector of indices
for (Polygons::const_iterator loop = loops.begin(); loop != loops.end(); ++loop) {
double a = loop->area();
area.push_back(a);
abs_area.push_back(std::fabs(a));
sorted_area.push_back(loop - loops.begin());
}
std::sort(sorted_area.begin(), sorted_area.end(), _area_comp(&abs_area)); // outer first
// we don't perform a safety offset now because it might reverse cw loops
Polygons p_slices;
for (std::vector<size_t>::const_iterator loop_idx = sorted_area.begin(); loop_idx != sorted_area.end(); ++loop_idx) {
/* we rely on the already computed area to determine the winding order
of the loops, since the Orientation() function provided by Clipper
would do the same, thus repeating the calculation */
Polygons::const_iterator loop = loops.begin() + *loop_idx;
if (area[*loop_idx] > +EPSILON)
p_slices.push_back(*loop);
else if (area[*loop_idx] < -EPSILON)
p_slices = diff(p_slices, *loop);
}
// perform a safety offset to merge very close facets (TODO: find test case for this)
double safety_offset = scale_(0.0499);
ExPolygons ex_slices = offset2_ex(p_slices, +safety_offset, -safety_offset);
#ifdef SLIC3R_TRIANGLEMESH_DEBUG
size_t holes_count = 0;
for (ExPolygons::const_iterator e = ex_slices.begin(); e != ex_slices.end(); ++e) {
holes_count += e->holes.size();
}
printf(PRINTF_ZU " surface(s) having " PRINTF_ZU " holes detected from " PRINTF_ZU " polylines\n",
ex_slices.size(), holes_count, loops.size());
#endif
// append to the supplied collection
expolygons_append(*slices, ex_slices);
}
void
TriangleMeshSlicer::make_expolygons(std::vector<IntersectionLine> &lines, ExPolygons* slices) const
{
Polygons pp;
this->make_loops(lines, &pp);
this->make_expolygons(pp, slices);
}
void
TriangleMeshSlicer::cut(float z, TriangleMesh* upper, TriangleMesh* lower) const
{
IntersectionLines upper_lines, lower_lines;
float scaled_z = scale_(z);
for (int facet_idx = 0; facet_idx < this->mesh->stl.stats.number_of_facets; facet_idx++) {
stl_facet* facet = &this->mesh->stl.facet_start[facet_idx];
// find facet extents
float min_z = fminf(facet->vertex[0].z, fminf(facet->vertex[1].z, facet->vertex[2].z));
float max_z = fmaxf(facet->vertex[0].z, fmaxf(facet->vertex[1].z, facet->vertex[2].z));
// intersect facet with cutting plane
IntersectionLines lines;
this->slice_facet(scaled_z, *facet, facet_idx, min_z, max_z, &lines);
// save intersection lines for generating correct triangulations
for (IntersectionLines::const_iterator it = lines.begin(); it != lines.end(); ++it) {
if (it->edge_type == feTop) {
lower_lines.push_back(*it);
} else if (it->edge_type == feBottom) {
upper_lines.push_back(*it);
} else if (it->edge_type != feHorizontal) {
lower_lines.push_back(*it);
upper_lines.push_back(*it);
}
}
if (min_z > z || (min_z == z && max_z > min_z)) {
// facet is above the cut plane and does not belong to it
if (upper != NULL) stl_add_facet(&upper->stl, facet);
} else if (max_z < z || (max_z == z && max_z > min_z)) {
// facet is below the cut plane and does not belong to it
if (lower != NULL) stl_add_facet(&lower->stl, facet);
} else if (min_z < z && max_z > z) {
// facet is cut by the slicing plane
// look for the vertex on whose side of the slicing plane there are no other vertices
int isolated_vertex;
if ( (facet->vertex[0].z > z) == (facet->vertex[1].z > z) ) {
isolated_vertex = 2;
} else if ( (facet->vertex[1].z > z) == (facet->vertex[2].z > z) ) {
isolated_vertex = 0;
} else {
isolated_vertex = 1;
}
// get vertices starting from the isolated one
stl_vertex* v0 = &facet->vertex[isolated_vertex];
stl_vertex* v1 = &facet->vertex[(isolated_vertex+1) % 3];
stl_vertex* v2 = &facet->vertex[(isolated_vertex+2) % 3];
// intersect v0-v1 and v2-v0 with cutting plane and make new vertices
stl_vertex v0v1, v2v0;
v0v1.x = v1->x + (v0->x - v1->x) * (z - v1->z) / (v0->z - v1->z);
v0v1.y = v1->y + (v0->y - v1->y) * (z - v1->z) / (v0->z - v1->z);
v0v1.z = z;
v2v0.x = v2->x + (v0->x - v2->x) * (z - v2->z) / (v0->z - v2->z);
v2v0.y = v2->y + (v0->y - v2->y) * (z - v2->z) / (v0->z - v2->z);
v2v0.z = z;
// build the triangular facet
stl_facet triangle;
triangle.normal = facet->normal;
triangle.vertex[0] = *v0;
triangle.vertex[1] = v0v1;
triangle.vertex[2] = v2v0;
// build the facets forming a quadrilateral on the other side
stl_facet quadrilateral[2];
quadrilateral[0].normal = facet->normal;
quadrilateral[0].vertex[0] = *v1;
quadrilateral[0].vertex[1] = *v2;
quadrilateral[0].vertex[2] = v0v1;
quadrilateral[1].normal = facet->normal;
quadrilateral[1].vertex[0] = *v2;
quadrilateral[1].vertex[1] = v2v0;
quadrilateral[1].vertex[2] = v0v1;
if (v0->z > z) {
if (upper != NULL) stl_add_facet(&upper->stl, &triangle);
if (lower != NULL) {
stl_add_facet(&lower->stl, &quadrilateral[0]);
stl_add_facet(&lower->stl, &quadrilateral[1]);
}
} else {
if (upper != NULL) {
stl_add_facet(&upper->stl, &quadrilateral[0]);
stl_add_facet(&upper->stl, &quadrilateral[1]);
}
if (lower != NULL) stl_add_facet(&lower->stl, &triangle);
}
}
}
// triangulate holes of upper mesh
if (upper != NULL) {
// compute shape of section
ExPolygons section;
this->make_expolygons_simple(upper_lines, &section);
// triangulate section
Polygons triangles;
for (ExPolygons::const_iterator expolygon = section.begin(); expolygon != section.end(); ++expolygon)
expolygon->triangulate_p2t(&triangles);
// convert triangles to facets and append them to mesh
for (Polygons::const_iterator polygon = triangles.begin(); polygon != triangles.end(); ++polygon) {
Polygon p = *polygon;
p.reverse();
stl_facet facet;
facet.normal.x = 0;
facet.normal.y = 0;
facet.normal.z = -1;
for (size_t i = 0; i <= 2; ++i) {
facet.vertex[i].x = unscale(p.points[i].x);
facet.vertex[i].y = unscale(p.points[i].y);
facet.vertex[i].z = z;
}
stl_add_facet(&upper->stl, &facet);
}
}
// triangulate holes of lower mesh
if (lower != NULL) {
// compute shape of section
ExPolygons section;
this->make_expolygons_simple(lower_lines, &section);
// triangulate section
Polygons triangles;
for (ExPolygons::const_iterator expolygon = section.begin(); expolygon != section.end(); ++expolygon)
expolygon->triangulate_p2t(&triangles);
// convert triangles to facets and append them to mesh
for (Polygons::const_iterator polygon = triangles.begin(); polygon != triangles.end(); ++polygon) {
stl_facet facet;
facet.normal.x = 0;
facet.normal.y = 0;
facet.normal.z = 1;
for (size_t i = 0; i <= 2; ++i) {
facet.vertex[i].x = unscale(polygon->points[i].x);
facet.vertex[i].y = unscale(polygon->points[i].y);
facet.vertex[i].z = z;
}
stl_add_facet(&lower->stl, &facet);
}
}
stl_get_size(&(upper->stl));
stl_get_size(&(lower->stl));
}
TriangleMeshSlicer::TriangleMeshSlicer(TriangleMesh* _mesh) : mesh(_mesh), v_scaled_shared(NULL)
{
// build a table to map a facet_idx to its three edge indices
this->mesh->require_shared_vertices();
typedef std::pair<int,int> t_edge;
typedef std::vector<t_edge> t_edges; // edge_idx => a_id,b_id
typedef std::map<t_edge,int> t_edges_map; // a_id,b_id => edge_idx
this->facets_edges.resize(this->mesh->stl.stats.number_of_facets);
{
t_edges edges;
// reserve() instad of resize() because otherwise we couldn't read .size() below to assign edge_idx
edges.reserve(this->mesh->stl.stats.number_of_facets * 3); // number of edges = number of facets * 3
t_edges_map edges_map;
for (int facet_idx = 0; facet_idx < this->mesh->stl.stats.number_of_facets; facet_idx++) {
this->facets_edges[facet_idx].resize(3);
for (int i = 0; i <= 2; i++) {
int a_id = this->mesh->stl.v_indices[facet_idx].vertex[i];
int b_id = this->mesh->stl.v_indices[facet_idx].vertex[(i+1) % 3];
int edge_idx;
t_edges_map::const_iterator my_edge = edges_map.find(std::make_pair(b_id,a_id));
if (my_edge != edges_map.end()) {
edge_idx = my_edge->second;
} else {
/* 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 */
my_edge = edges_map.find(std::make_pair(a_id,b_id));
if (my_edge != edges_map.end()) {
edge_idx = my_edge->second;
} else {
// edge isn't listed in table, so we insert it
edge_idx = edges.size();
edges.push_back(std::make_pair(a_id,b_id));
edges_map[ edges[edge_idx] ] = edge_idx;
}
}
this->facets_edges[facet_idx][i] = edge_idx;
#ifdef SLIC3R_TRIANGLEMESH_DEBUG
printf(" [facet %d, edge %d] a_id = %d, b_id = %d --> edge %d\n", facet_idx, i, a_id, b_id, edge_idx);
#endif
}
}
}
// clone shared vertices coordinates and scale them
this->v_scaled_shared = (stl_vertex*)calloc(this->mesh->stl.stats.shared_vertices, sizeof(stl_vertex));
std::copy(this->mesh->stl.v_shared, this->mesh->stl.v_shared + this->mesh->stl.stats.shared_vertices, this->v_scaled_shared);
for (int i = 0; i < this->mesh->stl.stats.shared_vertices; i++) {
this->v_scaled_shared[i].x /= SCALING_FACTOR;
this->v_scaled_shared[i].y /= SCALING_FACTOR;
this->v_scaled_shared[i].z /= SCALING_FACTOR;
}
}
TriangleMeshSlicer::~TriangleMeshSlicer()
{
if (this->v_scaled_shared != NULL) free(this->v_scaled_shared);
}
// Generate the vertex list for a cube solid of arbitrary size in X/Y/Z.
TriangleMesh make_cube(double x, double y, double z) {
Pointf3 pv[8] = {
Pointf3(x, y, 0), Pointf3(x, 0, 0), Pointf3(0, 0, 0),
Pointf3(0, y, 0), Pointf3(x, y, z), Pointf3(0, y, z),
Pointf3(0, 0, z), Pointf3(x, 0, z)
};
Point3 fv[12] = {
Point3(0, 1, 2), Point3(0, 2, 3), Point3(4, 5, 6),
Point3(4, 6, 7), Point3(0, 4, 7), Point3(0, 7, 1),
Point3(1, 7, 6), Point3(1, 6, 2), Point3(2, 6, 5),
Point3(2, 5, 3), Point3(4, 0, 3), Point3(4, 3, 5)
};
std::vector<Point3> facets(&fv[0], &fv[0]+12);
Pointf3s vertices(&pv[0], &pv[0]+8);
TriangleMesh mesh(vertices ,facets);
return mesh;
}
// Generate the mesh for a cylinder and return it, using
// the generated angle to calculate the top mesh triangles.
TriangleMesh make_cylinder(double r, double h, double fa) {
Pointf3s vertices;
std::vector<Point3> facets;
// 2 special vertices, top and bottom center, rest are relative to this
vertices.push_back(Pointf3(0.0, 0.0, 0.0));
vertices.push_back(Pointf3(0.0, 0.0, h));
// adjust via rounding
double angle = (2*PI / floor(2*PI / fa));
// 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.
unsigned id = 3;
vertices.push_back(Pointf3(sin(0) * r , cos(0) * r, 0));
vertices.push_back(Pointf3(sin(0) * r , cos(0) * r, h));
for (double i = angle; i < 2*PI; i+=angle) {
vertices.push_back(Pointf3(sin(i) * r , cos(i) * r, 0));
vertices.push_back(Pointf3(sin(i) * r , cos(i) * r, h));
id += 2;
facets.push_back(Point3(0, id - 1, id - 3));
facets.push_back(Point3(1, id, id - 2));
facets.push_back(Point3(id, id - 1, id - 3));
facets.push_back(Point3(id - 3, id - 2, id));
}
facets.push_back(Point3(0, 2, id -1));
facets.push_back(Point3(1, 3, id));
facets.push_back(Point3(id - 1, 2, 3));
facets.push_back(Point3(id - 1, 3, id));
TriangleMesh mesh(vertices ,facets);
return mesh;
}
}