Fixes of the offset curves from Voronoi diagram.

The offset curve extractor is already quite usable,
though singular cases are still not covered yet
when the offset curve intersects or nearly intersects
a Voronoi vertex.

Removal of the PRINTF_ZU "%zu" Visual Studio printf compatibility macro.
Fixes of a contours self intersection test for collinear segments.
SVG exporter now exports white background, so that the GNOME Eye viewer is usable.
This commit is contained in:
Vojtech Bubnik 2020-06-16 13:13:51 +02:00
parent af5c3583e8
commit b101a8e266
16 changed files with 749 additions and 343 deletions

View File

@ -53,7 +53,7 @@ void BridgeDetector::initialize()
this->_edges = intersection_pl(to_polylines(grown), contours);
#ifdef SLIC3R_DEBUG
printf(" bridge has " PRINTF_ZU " support(s)\n", this->_edges.size());
printf(" bridge has %zu support(s)\n", this->_edges.size());
#endif
// detect anchors as intersection between our bridge expolygon and the lower slices

View File

@ -1586,12 +1586,17 @@ std::vector<std::pair<EdgeGrid::Grid::ContourEdge, EdgeGrid::Grid::ContourEdge>>
++ cnt;
}
}
std::vector<std::pair<EdgeGrid::Grid::ContourEdge, EdgeGrid::Grid::ContourEdge>> out;
if (cnt > 0) {
len /= double(cnt);
bbox.offset(20);
EdgeGrid::Grid grid;
grid.set_bbox(bbox);
grid.create(polygons, len);
return grid.intersecting_edges();
out = grid.intersecting_edges();
}
return out;
}
// Find all pairs of intersectiong edges from the set of polygons, highlight them in an SVG.

View File

@ -404,7 +404,7 @@ void ExPolygon::triangulate_pp(Polygons* polygons) const
{
TPPLPoly p;
p.Init(int(ex->contour.points.size()));
//printf(PRINTF_ZU "\n0\n", ex->contour.points.size());
//printf("%zu\n0\n", ex->contour.points.size());
for (const Point &point : ex->contour.points) {
size_t i = &point - &ex->contour.points.front();
p[i].x = point(0);
@ -419,7 +419,7 @@ void ExPolygon::triangulate_pp(Polygons* polygons) const
for (Polygons::const_iterator hole = ex->holes.begin(); hole != ex->holes.end(); ++hole) {
TPPLPoly p;
p.Init(hole->points.size());
//printf(PRINTF_ZU "\n1\n", hole->points.size());
//printf("%zu\n1\n", hole->points.size());
for (const Point &point : hole->points) {
size_t i = &point - &hole->points.front();
p[i].x = point(0);

View File

@ -1218,7 +1218,7 @@ bool store_amf(const char* path, Model* model, const DynamicPrintConfig* config,
for (ModelInstance *instance : object->instances) {
char buf[512];
sprintf(buf,
" <instance objectid=\"" PRINTF_ZU "\">\n"
" <instance objectid=\"%zu\">\n"
" <deltax>%lf</deltax>\n"
" <deltay>%lf</deltay>\n"
" <deltaz>%lf</deltaz>\n"

View File

@ -393,7 +393,7 @@ GCodeSender::on_read(const boost::system::error_code& error,
}
this->send();
} else {
printf("Cannot resend " PRINTF_ZU " (oldest we have is " PRINTF_ZU ")\n", toresend, this->sent - this->last_sent.size());
printf("Cannot resend %zu (oldest we have is %zu)\n", toresend, this->sent - this->last_sent.size());
}
} else if (boost::starts_with(line, "wait")) {
// ignore

View File

@ -471,7 +471,7 @@ Pointfs arrange(size_t num_parts, const Vec2d &part_size, coordf_t gap, const Bo
size_t cellw = size_t(floor((bed_bbox.size()(0) + gap) / cell_size(0)));
size_t cellh = size_t(floor((bed_bbox.size()(1) + gap) / cell_size(1)));
if (num_parts > cellw * cellh)
throw std::invalid_argument(PRINTF_ZU " parts won't fit in your print area!\n", num_parts);
throw std::invalid_argument("%zu parts won't fit in your print area!\n", num_parts);
// Get a bounding box of cellw x cellh cells, centered at the center of the bed.
Vec2d cells_size(cellw * cell_size(0) - gap, cellh * cell_size(1) - gap);

View File

@ -115,32 +115,94 @@ inline bool segment_segment_intersection(const Vec2d &p1, const Vec2d &v1, const
return true;
}
inline int segments_could_intersect(
inline bool segments_intersect(
const Slic3r::Point &ip1, const Slic3r::Point &ip2,
const Slic3r::Point &jp1, const Slic3r::Point &jp2)
{
assert(ip1 != ip2);
assert(jp1 != jp2);
auto segments_could_intersect = [](
const Slic3r::Point &ip1, const Slic3r::Point &ip2,
const Slic3r::Point &jp1, const Slic3r::Point &jp2) -> std::pair<int, int>
{
Vec2i64 iv = (ip2 - ip1).cast<int64_t>();
Vec2i64 vij1 = (jp1 - ip1).cast<int64_t>();
Vec2i64 vij2 = (jp2 - ip1).cast<int64_t>();
int64_t tij1 = cross2(iv, vij1);
int64_t tij2 = cross2(iv, vij2);
int sij1 = (tij1 > 0) ? 1 : ((tij1 < 0) ? -1 : 0); // signum
int sij2 = (tij2 > 0) ? 1 : ((tij2 < 0) ? -1 : 0);
return sij1 * sij2;
return std::make_pair(
// signum
(tij1 > 0) ? 1 : ((tij1 < 0) ? -1 : 0),
(tij2 > 0) ? 1 : ((tij2 < 0) ? -1 : 0));
};
std::pair<int, int> sign1 = segments_could_intersect(ip1, ip2, jp1, jp2);
std::pair<int, int> sign2 = segments_could_intersect(jp1, jp2, ip1, ip2);
int test1 = sign1.first * sign1.second;
int test2 = sign2.first * sign2.second;
if (test1 <= 0 && test2 <= 0) {
// The segments possibly intersect. They may also be collinear, but not intersect.
if (test1 != 0 || test2 != 0)
// Certainly not collinear, then the segments intersect.
return true;
// If the first segment is collinear with the other, the other is collinear with the first segment.
assert((sign1.first == 0 && sign1.second == 0) == (sign2.first == 0 && sign2.second == 0));
if (sign1.first == 0 && sign1.second == 0) {
// The segments are certainly collinear. Now verify whether they overlap.
Slic3r::Point vi = ip2 - ip1;
// Project both on the longer coordinate of vi.
int axis = std::abs(vi.x()) > std::abs(vi.y()) ? 0 : 1;
coord_t i = ip1(axis);
coord_t j = ip2(axis);
coord_t k = jp1(axis);
coord_t l = jp2(axis);
if (i > j)
std::swap(i, j);
if (k > l)
std::swap(k, l);
return (k >= i && k <= j) || (i >= k && i <= l);
}
}
return false;
}
inline bool segments_intersect(
const Slic3r::Point &ip1, const Slic3r::Point &ip2,
const Slic3r::Point &jp1, const Slic3r::Point &jp2)
template<typename T> inline T foot_pt(const T &line_pt, const T &line_dir, const T &pt)
{
return segments_could_intersect(ip1, ip2, jp1, jp2) <= 0 &&
segments_could_intersect(jp1, jp2, ip1, ip2) <= 0;
T v = pt - line_pt;
auto l2 = line_dir.squaredNorm();
auto t = (l2 == 0) ? 0 : v.dot(line_dir) / l2;
return line_pt + line_dir * t;
}
inline Vec2d foot_pt(const Line &iline, const Point &ipt)
{
return foot_pt<Vec2d>(iline.a.cast<double>(), (iline.b - iline.a).cast<double>(), ipt.cast<double>());
}
template<typename T> inline auto ray_point_distance_squared(const T &ray_pt, const T &ray_dir, const T &pt)
{
return (foot_pt(ray_pt, ray_dir, pt) - pt).squaredNorm();
}
template<typename T> inline auto ray_point_distance(const T &ray_pt, const T &ray_dir, const T &pt)
{
return (foot_pt(ray_pt, ray_dir, pt) - pt).norm();
}
inline double ray_point_distance_squared(const Line &iline, const Point &ipt)
{
return (foot_pt(iline, ipt) - ipt.cast<double>()).squaredNorm();
}
inline double ray_point_distance(const Line &iline, const Point &ipt)
{
return (foot_pt(iline, ipt) - ipt.cast<double>()).norm();
}
// Based on Liang-Barsky function by Daniel White @ http://www.skytopia.com/project/articles/compsci/clipping.html
template<typename T>
bool liang_barsky_line_clipping(
inline bool liang_barsky_line_clipping(
// Start and end points of the source line, result will be stored there as well.
Eigen::Matrix<T, 2, 1, Eigen::DontAlign> &x0,
Eigen::Matrix<T, 2, 1, Eigen::DontAlign> &x1,

View File

@ -264,7 +264,7 @@ void LayerRegion::process_external_surfaces(const Layer *lower_layer, const Poly
this->flow(frInfill, true).scaled_width()
);
#ifdef SLIC3R_DEBUG
printf("Processing bridge at layer " PRINTF_ZU ":\n", this->layer()->id());
printf("Processing bridge at layer %zu:\n", this->layer()->id());
#endif
double custom_angle = Geometry::deg2rad(this->region()->config().bridge_angle.value);
if (bd.detect_angle(custom_angle)) {

View File

@ -153,9 +153,11 @@ inline Lines to_lines(const Polygon &poly)
{
Lines lines;
lines.reserve(poly.points.size());
if (poly.points.size() > 2) {
for (Points::const_iterator it = poly.points.begin(); it != poly.points.end()-1; ++it)
lines.push_back(Line(*it, *(it + 1)));
lines.push_back(Line(poly.points.back(), poly.points.front()));
}
return lines;
}

View File

@ -1431,7 +1431,7 @@ void PrintObject::bridge_over_infill()
}
#ifdef SLIC3R_DEBUG
printf("Bridging " PRINTF_ZU " internal areas at layer " PRINTF_ZU "\n", to_bridge.size(), layer->id());
printf("Bridging %zu internal areas at layer %zu\n", to_bridge.size(), layer->id());
#endif
// compute the remaning internal solid surfaces as difference

View File

@ -21,6 +21,7 @@ bool SVG::open(const char* afilename)
" <polyline fill=\"darkblue\" points=\"0,0 10,5 0,10 1,5\" />\n"
" </marker>\n"
);
fprintf(this->f, "<rect fill='white' stroke='none' x='0' y='0' width='%f' height='%f'/>\n", 2000.f, 2000.f);
return true;
}
@ -42,6 +43,7 @@ bool SVG::open(const char* afilename, const BoundingBox &bbox, const coord_t bbo
" <polyline fill=\"darkblue\" points=\"0,0 10,5 0,10 1,5\" />\n"
" </marker>\n",
h, w);
fprintf(this->f, "<rect fill='white' stroke='none' x='0' y='0' width='%f' height='%f'/>\n", w, h);
return true;
}

View File

@ -952,7 +952,7 @@ void TriangleMeshSlicer::slice(const std::vector<float> &z, SlicingMode mode, co
[&layers_p, mode, closing_radius, layers, throw_on_cancel, this](const tbb::blocked_range<size_t>& range) {
for (size_t layer_id = range.begin(); layer_id < range.end(); ++ layer_id) {
#ifdef SLIC3R_TRIANGLEMESH_DEBUG
printf("Layer " PRINTF_ZU " (slice_z = %.2f):\n", layer_id, z[layer_id]);
printf("Layer %zu (slice_z = %.2f):\n", layer_id, z[layer_id]);
#endif
throw_on_cancel();
ExPolygons &expolygons = (*layers)[layer_id];
@ -1779,7 +1779,7 @@ void TriangleMeshSlicer::make_expolygons(const Polygons &loops, const float clos
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",
printf("%zu surface(s) having %zu holes detected from %zu polylines\n",
ex_slices.size(), holes_count, loops.size());
#endif

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@ -15,7 +15,8 @@ namespace Slic3r {
using VD = Geometry::VoronoiDiagram;
namespace detail {
// Intersect a circle with a ray, return the two parameters
// Intersect a circle with a ray, return the two parameters.
// Currently used for unbounded Voronoi edges only.
double first_circle_segment_intersection_parameter(
const Vec2d &center, const double r, const Vec2d &pt, const Vec2d &v)
{
@ -61,70 +62,109 @@ namespace detail {
// Return maximum two points, that are at distance "d" from both points
Intersections point_point_equal_distance_points(const Point &pt1, const Point &pt2, const double d)
{
// input points
const auto cx = double(pt1.x());
const auto cy = double(pt1.y());
const auto qx = double(pt2.x());
const auto qy = double(pt2.y());
// Calculating determinant.
auto x0 = 2. * qy;
auto cx2 = cx * cx;
auto cy2 = cy * cy;
auto x5 = 2 * cx * qx;
auto x6 = cy * x0;
auto qx2 = qx * qx;
auto qy2 = qy * qy;
auto x9 = qx2 + qy2;
auto x10 = cx2 + cy2 - x5 - x6 + x9;
auto x11 = - cx2 - cy2;
auto discr = x10 * (4. * d + x11 + x5 + x6 - qx2 - qy2);
if (discr < 0.)
// Calculate the two intersection points.
// With the help of Python package sympy:
// res = solve([(x - cx)**2 + (y - cy)**2 - d**2, x**2 + y**2 - d**2], [x, y])
// ccode(cse((res[0][0], res[0][1], res[1][0], res[1][1])))
// where cx, cy is the center of pt1 relative to pt2,
// d is distance from the line and the point (0, 0).
// The result is then shifted to pt2.
auto cx = double(pt1.x() - pt2.x());
auto cy = double(pt1.y() - pt2.y());
double cl = cx * cx + cy * cy;
double discr = 4. * d * d - cl;
if (discr < 0.) {
// No intersection point found, the two circles are too far away.
return Intersections { 0, { Vec2d(), Vec2d() } };
}
// Avoid division by zero if a gets too small.
bool xy_swapped = std::abs(cx) < std::abs(cy);
if (xy_swapped)
std::swap(cx, cy);
double u;
int cnt;
if (discr == 0.) {
cnt = 1;
u = 0;
} else {
cnt = 2;
u = 0.5 * cx * sqrt(cl * discr) / cl;
}
double v = 0.5 * cy - u;
double w = 2. * cy;
double e = 0.5 / cx;
double f = 0.5 * cy + u;
Intersections out { cnt, { Vec2d(-e * (v * w - cl), v),
Vec2d(-e * (w * f - cl), f) } };
if (xy_swapped) {
std::swap(out.pts[0].x(), out.pts[0].y());
std::swap(out.pts[1].x(), out.pts[1].y());
}
out.pts[0] += pt2.cast<double>();
out.pts[1] += pt2.cast<double>();
// Some intersections are found.
int npoints = (discr > 0) ? 2 : 1;
auto x1 = 2. * cy - x0;
auto x2 = cx - qx;
auto x12 = 0.5 * x2 * sqrt(discr) / x10;
auto x13 = 0.5 * (cy + qy);
auto x14 = - x12 + x13;
auto x15 = x11 + x9;
auto x16 = 0.5 / x2;
auto x17 = x12 + x13;
return Intersections { npoints, { Vec2d(- x16 * (x1 * x14 + x15), x14),
Vec2d(- x16 * (x1 * x17 + x15), x17) } };
assert(std::abs((out.pts[0] - pt1.cast<double>()).norm() - d) < SCALED_EPSILON);
assert(std::abs((out.pts[1] - pt1.cast<double>()).norm() - d) < SCALED_EPSILON);
assert(std::abs((out.pts[0] - pt2.cast<double>()).norm() - d) < SCALED_EPSILON);
assert(std::abs((out.pts[1] - pt2.cast<double>()).norm() - d) < SCALED_EPSILON);
return out;
}
// Return maximum two points, that are at distance "d" from both the line and point.
Intersections line_point_equal_distance_points(const Line &line, const Point &pt, const double d)
Intersections line_point_equal_distance_points(const Line &line, const Point &ipt, const double d)
{
assert(line.a != pt && line.b != pt);
assert(line.a != ipt && line.b != ipt);
// Calculating two points of distance "d" to a ray and a point.
// Point.
auto x0 = double(pt.x());
auto y0 = double(pt.y());
// Ray equation. Vector (a, b) is perpendicular to line.
auto a = double(line.a.y() - line.b.y());
auto b = double(line.b.x() - line.a.x());
// pt shall not lie on line.
assert(std::abs((x0 - line.a.x()) * a + (y0 - line.a.y()) * b) < SCALED_EPSILON);
// Orient line so that the vector (a, b) points towards pt.
if (a * (x0 - line.a.x()) + b * (y0 - line.a.y()) < 0.)
std::swap(x0, y0);
double c = - a * double(line.a.x()) - b * double(line.a.y());
// Calculate the two points.
double a2 = a * a;
double b2 = b * b;
double a2b2 = a2 + b2;
double d2 = d * d;
double s = a2*d2 - a2*sqr(x0) - 2*a*b*x0*y0 - 2*a*c*x0 + 2*a*d*x0 + b2*d2 - b2*sqr(y0) - 2*b*c*y0 + 2*b*d*y0 - sqr(c) + 2*c*d - d2;
Vec2d pt = ipt.cast<double>();
Vec2d lv = (line.b - line.a).cast<double>();
double l2 = lv.squaredNorm();
Vec2d lpv = (line.a - ipt).cast<double>();
double c = cross2(lpv, lv);
if (c < 0) {
lv = - lv;
c = - c;
}
// Line equation (ax + by + c - d * sqrt(l2)).
auto a = - lv.y();
auto b = lv.x();
// Line point shifted by -ipt is on the line.
assert(std::abs(lpv.x() * a + lpv.y() * b + c) < SCALED_EPSILON);
// Line vector (a, b) points towards ipt.
assert(a * lpv.x() + b * lpv.y() < - SCALED_EPSILON);
#ifndef NDEBUG
{
// Foot point of ipt on line.
Vec2d ft = Geometry::foot_pt(line, ipt);
// Center point between ipt and line, its distance to both line and ipt is equal.
Vec2d centerpt = 0.5 * (ft + pt) - pt;
double dcenter = 0.5 * (ft - pt).norm();
// Verify that the center point
assert(std::abs(centerpt.x() * a + centerpt.y() * b + c - dcenter * sqrt(l2)) < SCALED_EPSILON * sqrt(l2));
}
#endif // NDEBUG
// Calculate the two intersection points.
// With the help of Python package sympy:
// res = solve([a * x + b * y + c - d * sqrt(a**2 + b**2), x**2 + y**2 - d**2], [x, y])
// ccode(cse((res[0][0], res[0][1], res[1][0], res[1][1])))
// where (a, b, c, d) is the line equation, not normalized (vector a,b is not normalized),
// d is distance from the line and the point (0, 0).
// The result is then shifted to ipt.
double dscaled = d * sqrt(l2);
double s = c * (2. * dscaled - c);
if (s < 0.)
// Distance of pt from line is bigger than 2 * d.
return Intersections { 0 };
double u;
int cnt;
// Avoid division by zero if a gets too small.
bool xy_swapped = std::abs(a) < std::abs(b);
if (xy_swapped)
std::swap(a, b);
if (s == 0.) {
// Distance of pt from line is 2 * d.
cnt = 1;
@ -132,105 +172,29 @@ namespace detail {
} else {
// Distance of pt from line is smaller than 2 * d.
cnt = 2;
u = a*sqrt(s)/a2b2;
u = a * sqrt(s) / l2;
}
double v = (-a2*y0 + a*b*x0 + b*c - b*d)/a2b2;
return Intersections { cnt, { Vec2d((b * ( u + v) - c + d) / a, - u - v),
Vec2d((b * (- u + v) - c + d) / a, u - v) } };
double e = dscaled - c;
double f = b * e / l2;
double g = f - u;
double h = f + u;
Intersections out { cnt, { Vec2d((- b * g + e) / a, g),
Vec2d((- b * h + e) / a, h) } };
if (xy_swapped) {
std::swap(out.pts[0].x(), out.pts[0].y());
std::swap(out.pts[1].x(), out.pts[1].y());
}
out.pts[0] += pt;
out.pts[1] += pt;
assert(std::abs(Geometry::ray_point_distance<Vec2d>(line.a.cast<double>(), (line.b - line.a).cast<double>(), out.pts[0]) - d) < SCALED_EPSILON);
assert(std::abs(Geometry::ray_point_distance<Vec2d>(line.a.cast<double>(), (line.b - line.a).cast<double>(), out.pts[1]) - d) < SCALED_EPSILON);
assert(std::abs((out.pts[0] - ipt.cast<double>()).norm() - d) < SCALED_EPSILON);
assert(std::abs((out.pts[1] - ipt.cast<double>()).norm() - d) < SCALED_EPSILON);
return out;
}
Vec2d voronoi_edge_offset_point(
const VD &vd,
const Lines &lines,
// Distance of a VD vertex to the closest site (input polygon edge or vertex).
const std::vector<double> &vertex_dist,
// Minium distance of a VD edge to the closest site (input polygon edge or vertex).
// For a parabolic segment the distance may be smaller than the distance of the two end points.
const std::vector<double> &edge_dist,
// Edge for which to calculate the offset point. If the distance towards the input polygon
// is not monotonical, pick the offset point closer to edge.vertex0().
const VD::edge_type &edge,
// Distance from the input polygon along the edge.
const double offset_distance)
{
const VD::vertex_type *v0 = edge.vertex0();
const VD::vertex_type *v1 = edge.vertex1();
const VD::cell_type *cell = edge.cell();
const VD::cell_type *cell2 = edge.twin()->cell();
const Line &line0 = lines[cell->source_index()];
const Line &line1 = lines[cell2->source_index()];
if (v0 == nullptr || v1 == nullptr) {
assert(edge.is_infinite());
assert(v0 != nullptr || v1 != nullptr);
// Offsetting on an unconstrained edge.
assert(offset_distance > vertex_dist[(v0 ? v0 : v1) - &vd.vertices().front()] - EPSILON);
Vec2d pt, dir;
double t;
if (cell->contains_point() && cell2->contains_point()) {
const Point &pt0 = (cell->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line0.a : line0.b;
const Point &pt1 = (cell2->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line1.a : line1.b;
// Direction vector of this unconstrained Voronoi edge.
dir = Vec2d(double(pt0.y() - pt1.y()), double(pt1.x() - pt0.x()));
if (v0 == nullptr) {
v0 = v1;
dir = - dir;
}
pt = Vec2d(v0->x(), v0->y());
t = detail::first_circle_segment_intersection_parameter(Vec2d(pt0.x(), pt0.y()), offset_distance, pt, dir);
} else {
// Infinite edges could not be created by two segment sites.
assert(cell->contains_point() != cell2->contains_point());
// Linear edge goes through the endpoint of a segment.
assert(edge.is_linear());
assert(edge.is_secondary());
const Line &line = cell->contains_segment() ? line0 : line1;
const Point &ipt = cell->contains_segment() ?
((cell2->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line1.a : line1.b) :
((cell->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line0.a : line0.b);
assert(line.a == ipt || line.b == ipt);
pt = Vec2d(ipt.x(), ipt.y());
dir = Vec2d(line.a.y() - line.b.y(), line.b.x() - line.a.x());
assert(dir.norm() > 0.);
t = offset_distance / dir.norm();
if (((line.a == ipt) == cell->contains_point()) == (v0 == nullptr))
t = - t;
}
return pt + t * dir;
} else {
// Constrained edge.
Vec2d p0(v0->x(), v0->y());
Vec2d p1(v1->x(), v1->y());
double d0 = vertex_dist[v0 - &vd.vertices().front()];
double d1 = vertex_dist[v1 - &vd.vertices().front()];
if (cell->contains_segment() && cell2->contains_segment()) {
// This edge is a bisector of two line segments. Distance to the input polygon increases/decreases monotonically.
double ddif = d1 - d0;
assert(offset_distance > std::min(d0, d1) - EPSILON && offset_distance < std::max(d0, d1) + EPSILON);
double t = (ddif == 0) ? 0. : clamp(0., 1., (offset_distance - d0) / ddif);
return Slic3r::lerp(p0, p1, t);
} else {
// One cell contains a point, the other contains an edge or a point.
assert(cell->contains_point() || cell2->contains_point());
const Point &ipt = cell->contains_point() ?
((cell->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line0.a : line0.b) :
((cell2->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line1.a : line1.b);
double t = detail::first_circle_segment_intersection_parameter(
Vec2d(ipt.x(), ipt.y()), offset_distance, p0, p1 - p0);
return Slic3r::lerp(p0, p1, t);
}
}
}
};
static Vec2d foot_pt(const Line &iline, const Point &ipt)
{
Vec2d pt = iline.a.cast<double>();
Vec2d dir = (iline.b - iline.a).cast<double>();
Vec2d v = ipt.cast<double>() - pt;
double l2 = dir.squaredNorm();
double t = (l2 == 0.) ? 0. : v.dot(dir) / l2;
return pt + dir * t;
}
} // namespace detail
Polygons voronoi_offset(
const Geometry::VoronoiDiagram &vd,
@ -259,20 +223,94 @@ Polygons voronoi_offset(
}
#endif // NDEBUG
enum class EdgeState : unsigned char {
// Initial state, don't know.
Unknown,
// This edge will certainly not be intersected by the offset curve.
Inactive,
// This edge will certainly be intersected by the offset curve.
Active,
// This edge will possibly be intersected by the offset curve.
Possible
};
enum class CellState : unsigned char {
// Initial state, don't know.
Unknown,
// Inactive cell is inside for outside curves and outside for inside curves.
Inactive,
// Active cell is outside for outside curves and inside for inside curves.
Active,
// Boundary cell is intersected by the input segment, part of it is active.
Boundary
};
// Mark edges with outward vertex pointing outside the polygons, thus there is a chance
// that such an edge will have an intersection with our desired offset curve.
bool outside = offset_distance > 0.;
std::vector<char> edge_candidate(vd.num_edges(), 2); // unknown state
std::vector<EdgeState> edge_state(vd.num_edges(), EdgeState::Unknown);
std::vector<CellState> cell_state(vd.num_cells(), CellState::Unknown);
const VD::edge_type *front_edge = &vd.edges().front();
const VD::cell_type *front_cell = &vd.cells().front();
auto set_edge_state_initial = [&edge_state, front_edge](const VD::edge_type *edge, EdgeState new_edge_type) {
EdgeState &edge_type = edge_state[edge - front_edge];
assert(edge_type == EdgeState::Unknown || edge_type == new_edge_type);
assert(new_edge_type == EdgeState::Possible || new_edge_type == EdgeState::Inactive);
edge_type = new_edge_type;
};
auto set_edge_state_final = [&edge_state, front_edge](const size_t edge_id, EdgeState new_edge_type) {
EdgeState &edge_type = edge_state[edge_id];
assert(edge_type == EdgeState::Possible || edge_type == new_edge_type);
assert(new_edge_type == EdgeState::Active || new_edge_type == EdgeState::Inactive);
edge_type = new_edge_type;
};
auto set_cell_state = [&cell_state, front_cell](const VD::cell_type *cell, CellState new_cell_type) -> bool {
CellState &cell_type = cell_state[cell - front_cell];
assert(cell_type == CellState::Active || cell_type == CellState::Inactive || cell_type == CellState::Boundary || cell_type == CellState::Unknown);
assert(new_cell_type == CellState::Active || new_cell_type == CellState::Inactive || new_cell_type == CellState::Boundary);
switch (cell_type) {
case CellState::Unknown:
break;
case CellState::Active:
if (new_cell_type == CellState::Inactive)
new_cell_type = CellState::Boundary;
break;
case CellState::Inactive:
if (new_cell_type == CellState::Active)
new_cell_type = CellState::Boundary;
break;
case CellState::Boundary:
return false;
}
if (cell_type != new_cell_type) {
cell_type = new_cell_type;
return true;
}
return false;
};
for (const VD::edge_type &edge : vd.edges())
if (edge.vertex1() == nullptr) {
// Infinite Voronoi edge separating two Point sites.
// Infinite Voronoi edge separating two Point sites or a Point site and a Segment site.
// Infinite edge is always outside and it has at least one valid vertex.
assert(edge.vertex0() != nullptr);
edge_candidate[&edge - front_edge] = outside;
set_edge_state_initial(&edge, outside ? EdgeState::Possible : EdgeState::Inactive);
// Opposite edge of an infinite edge is certainly not active.
edge_candidate[edge.twin() - front_edge] = 0;
} else if (edge.vertex1() != nullptr) {
set_edge_state_initial(edge.twin(), EdgeState::Inactive);
if (edge.is_secondary()) {
// edge.vertex0() must lie on source contour.
const VD::cell_type *cell = edge.cell();
const VD::cell_type *cell2 = edge.twin()->cell();
if (cell->contains_segment())
std::swap(cell, cell2);
// State of a cell containing a boundary point is known.
assert(cell->contains_point());
set_cell_state(cell, outside ? CellState::Active : CellState::Inactive);
// State of a cell containing a boundary edge is Boundary.
assert(cell2->contains_segment());
set_cell_state(cell2, CellState::Boundary);
}
} else if (edge.vertex0() != nullptr) {
// Finite edge.
const VD::cell_type *cell = edge.cell();
const Line *line = cell->contains_segment() ? &lines[cell->source_index()] : nullptr;
@ -282,37 +320,113 @@ Polygons voronoi_offset(
}
if (line) {
const VD::vertex_type *v1 = edge.vertex1();
const VD::cell_type *cell2 = (cell == edge.cell()) ? edge.twin()->cell() : edge.cell();
assert(v1);
const Point *pt_on_contour = nullptr;
if (cell == edge.cell() && edge.twin()->cell()->contains_segment()) {
// Constrained bisector of two segments.
// If the two segments share a point, then one end of the current Voronoi edge shares this point as well.
// Find pt_on_contour if it exists.
const Line &line2 = lines[cell2->source_index()];
if (line->a == line2.b)
pt_on_contour = &line->a;
else if (line->b == line2.a)
pt_on_contour = &line->b;
} else if (edge.is_secondary()) {
assert(edge.is_linear());
// One end of the current Voronoi edge shares a point of a contour.
assert(edge.cell()->contains_point() != edge.twin()->cell()->contains_point());
const Line &line2 = lines[cell2->source_index()];
pt_on_contour = &((cell2->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line2.a : line2.b);
}
if (pt_on_contour) {
// One end of the current Voronoi edge shares a point of a contour.
// Find out which one it is.
const VD::vertex_type *v0 = edge.vertex0();
Vec2d vec0(v0->x() - pt_on_contour->x(), v0->y() - pt_on_contour->y());
Vec2d vec1(v1->x() - pt_on_contour->x(), v1->y() - pt_on_contour->y());
double d0 = vec0.squaredNorm();
double d1 = vec1.squaredNorm();
assert(std::min(d0, d1) < SCALED_EPSILON * SCALED_EPSILON);
if (d0 < d1) {
// v0 is equal to pt.
} else {
// Skip secondary edge pointing to a contour point.
set_edge_state_initial(&edge, EdgeState::Inactive);
continue;
}
}
Vec2d l0(line->a.cast<double>());
Vec2d lv((line->b - line->a).cast<double>());
double side = cross2(lv, Vec2d(v1->x(), v1->y()) - l0);
edge_candidate[&edge - front_edge] = outside ? (side < 0.) : (side > 0.);
bool edge_active = outside ? (side < 0.) : (side > 0.);
set_edge_state_initial(&edge, edge_active ? EdgeState::Possible : EdgeState::Inactive);
assert(cell->contains_segment());
set_cell_state(cell,
pt_on_contour ? CellState::Boundary :
edge_active ? CellState::Active : CellState::Inactive);
set_cell_state(cell2,
(pt_on_contour && cell2->contains_segment()) ?
CellState::Boundary :
edge_active ? CellState::Active : CellState::Inactive);
}
}
{
// Perform one round of expansion marking Voronoi edges and cells next to boundary cells as active / inactive.
std::vector<const VD::cell_type*> cell_queue;
for (const VD::edge_type &edge : vd.edges())
if (edge_candidate[&edge - front_edge] == 2) {
if (edge_state[&edge - front_edge] == EdgeState::Unknown) {
assert(edge.cell()->contains_point() && edge.twin()->cell()->contains_point());
// Edge separating two point sources, not yet classified as inside / outside.
const VD::edge_type *e = &edge;
char state;
CellState cs = cell_state[edge.cell() - front_cell];
CellState cs2 = cell_state[edge.twin()->cell() - front_cell];
if (cs != CellState::Unknown || cs2 != CellState::Unknown) {
if (cs == CellState::Unknown) {
cs = cs2;
if (set_cell_state(edge.cell(), cs))
cell_queue.emplace_back(edge.cell());
} else if (set_cell_state(edge.twin()->cell(), cs))
cell_queue.emplace_back(edge.twin()->cell());
EdgeState es = (cs == CellState::Active) ? EdgeState::Possible : EdgeState::Inactive;
set_edge_state_initial(&edge, es);
set_edge_state_initial(edge.twin(), es);
} else {
const VD::edge_type *e = edge.twin()->rot_prev();
do {
state = edge_candidate[e - front_edge];
if (state != 2)
EdgeState es = edge_state[e->twin() - front_edge];
if (es != EdgeState::Unknown) {
assert(es == EdgeState::Possible || es == EdgeState::Inactive);
set_edge_state_initial(&edge, es);
CellState cs = (es == EdgeState::Possible) ? CellState::Active : CellState::Inactive;
if (set_cell_state(edge.cell(), cs))
cell_queue.emplace_back(edge.cell());
if (set_cell_state(edge.twin()->cell(), cs))
cell_queue.emplace_back(edge.twin()->cell());
break;
e = e->next();
} while (e != &edge);
e = &edge;
}
e = e->rot_prev();
} while (e != edge.twin());
}
}
// Do a final seed fill over Voronoi cells and unmarked Voronoi edges.
while (! cell_queue.empty()) {
const VD::cell_type *cell = cell_queue.back();
const CellState cs = cell_state[cell - front_cell];
cell_queue.pop_back();
const VD::edge_type *first_edge = cell->incident_edge();
const VD::edge_type *edge = cell->incident_edge();
EdgeState es = (cs == CellState::Active) ? EdgeState::Possible : EdgeState::Inactive;
do {
char &s = edge_candidate[e - front_edge];
if (s == 2) {
assert(e->cell()->contains_point() && e->twin()->cell()->contains_point());
assert(edge_candidate[e->twin() - front_edge] == 2);
s = state;
edge_candidate[e->twin() - front_edge] = state;
if (set_cell_state(edge->twin()->cell(), cs)) {
set_edge_state_initial(edge, es);
set_edge_state_initial(edge->twin(), es);
cell_queue.emplace_back(edge->twin()->cell());
}
e = e->next();
} while (e != &edge);
edge = edge->next();
} while (edge != first_edge);
}
}
if (! outside)
offset_distance = - offset_distance;
@ -323,10 +437,12 @@ Polygons voronoi_offset(
bbox.min -= (0.01 * bbox.size().cast<double>()).cast<coord_t>();
bbox.max += (0.01 * bbox.size().cast<double>()).cast<coord_t>();
}
static int irun = 0;
++ irun;
{
Lines helper_lines;
for (const VD::edge_type &edge : vd.edges())
if (edge_candidate[&edge - front_edge]) {
if (edge_state[&edge - front_edge] == EdgeState::Possible) {
const VD::vertex_type *v0 = edge.vertex0();
const VD::vertex_type *v1 = edge.vertex1();
assert(v0 != nullptr);
@ -370,16 +486,16 @@ Polygons voronoi_offset(
}
helper_lines.emplace_back(Line(Point(pt1.cast<coord_t>()), Point(((pt1 + pt2) * 0.5).cast<coord_t>())));
}
dump_voronoi_to_svg(debug_out_path("voronoi-offset-candidates1.svg").c_str(), vd, Points(), lines, Polygons(), helper_lines);
dump_voronoi_to_svg(debug_out_path("voronoi-offset-candidates1-%d.svg", irun).c_str(), vd, Points(), lines, Polygons(), helper_lines);
}
#endif // VORONOI_DEBUG_OUT
std::vector<Vec2d> edge_offset_point(vd.num_edges(), Vec2d());
const double offset_distance2 = offset_distance * offset_distance;
for (const VD::edge_type &edge : vd.edges()) {
assert(edge_candidate[&edge - front_edge] != 2);
assert(edge_state[&edge - front_edge] != EdgeState::Unknown);
size_t edge_idx = &edge - front_edge;
if (edge_candidate[edge_idx] == 1) {
if (edge_state[edge_idx] == EdgeState::Possible) {
// Edge candidate, intersection points were not calculated yet.
const VD::vertex_type *v0 = edge.vertex0();
const VD::vertex_type *v1 = edge.vertex1();
@ -391,11 +507,14 @@ Polygons voronoi_offset(
size_t edge_idx2 = edge.twin() - front_edge;
if (v1 == nullptr) {
assert(edge.is_infinite());
assert(edge_candidate[edge_idx2] == 0);
assert(edge.is_linear());
assert(edge_state[edge_idx2] == EdgeState::Inactive);
if (cell->contains_point() && cell2->contains_point()) {
assert(! edge.is_secondary());
const Point &pt0 = (cell->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line0.a : line0.b;
const Point &pt1 = (cell2->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line1.a : line1.b;
double dmin2 = (Vec2d(v0->x(), v0->y()) - pt0.cast<double>()).squaredNorm();
assert(dmin2 >= SCALED_EPSILON * SCALED_EPSILON);
if (dmin2 <= offset_distance2) {
// There shall be an intersection of this unconstrained edge with the offset curve.
// Direction vector of this unconstrained Voronoi edge.
@ -403,14 +522,13 @@ Polygons voronoi_offset(
Vec2d pt(v0->x(), v0->y());
double t = detail::first_circle_segment_intersection_parameter(Vec2d(pt0.x(), pt0.y()), offset_distance, pt, dir);
edge_offset_point[edge_idx] = pt + t * dir;
edge_candidate[edge_idx] = 3;
set_edge_state_final(edge_idx, EdgeState::Active);
} else
edge_candidate[edge_idx] = 0;
set_edge_state_final(edge_idx, EdgeState::Inactive);
} else {
// Infinite edges could not be created by two segment sites.
assert(cell->contains_point() != cell2->contains_point());
// Linear edge goes through the endpoint of a segment.
assert(edge.is_linear());
assert(edge.is_secondary());
const Point &ipt = cell->contains_segment() ?
((cell2->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line1.a : line1.b) :
@ -430,18 +548,13 @@ Polygons voronoi_offset(
// Infinite edge starts at an input contour, therefore there is always an intersection with an offset curve.
const Line &line = cell->contains_segment() ? line0 : line1;
assert(line.a == ipt || line.b == ipt);
Vec2d pt = ipt.cast<double>();
Vec2d dir(line.a.y() - line.b.y(), line.b.x() - line.a.x());
assert(dir.norm() > 0.);
double t = offset_distance / dir.norm();
if (((line.a == ipt) == cell->contains_point()) == (v0 == nullptr))
t = - t;
edge_offset_point[edge_idx] = pt + t * dir;
edge_candidate[edge_idx] = 3;
edge_offset_point[edge_idx] = ipt.cast<double>() + offset_distance * Vec2d(line.b.y() - line.a.y(), line.a.x() - line.b.x()).normalized();
set_edge_state_final(edge_idx, EdgeState::Active);
}
// The other edge of an unconstrained edge starting with null vertex shall never be intersected.
edge_candidate[edge_idx2] = 0;
set_edge_state_final(edge_idx2, EdgeState::Inactive);
} else if (edge.is_secondary()) {
assert(edge.is_linear());
assert(cell->contains_point() != cell2->contains_point());
const Line &line0 = lines[edge.cell()->source_index()];
const Line &line1 = lines[edge.twin()->cell()->source_index()];
@ -455,11 +568,11 @@ Polygons voronoi_offset(
double l2 = dir.squaredNorm();
if (offset_distance2 <= l2) {
edge_offset_point[edge_idx] = pt.cast<double>() + (offset_distance / sqrt(l2)) * dir;
edge_candidate[edge_idx] = 3;
set_edge_state_final(edge_idx, EdgeState::Active);
} else {
edge_candidate[edge_idx] = 0;
set_edge_state_final(edge_idx, EdgeState::Inactive);
}
edge_candidate[edge_idx2] = 0;
set_edge_state_final(edge_idx2, EdgeState::Inactive);
} else {
// Finite edge has valid points at both sides.
bool done = false;
@ -492,8 +605,8 @@ Polygons voronoi_offset(
}
double t = clamp(0., 1., (offset_distance - dmin) / ddif);
edge_offset_point[edge_idx] = Vec2d(lerp(v0->x(), v1->x(), t), lerp(v0->y(), v1->y(), t));
edge_candidate[edge_idx] = 3;
edge_candidate[edge_idx2] = 0;
set_edge_state_final(edge_idx, EdgeState::Active);
set_edge_state_final(edge_idx2, EdgeState::Inactive);
done = true;
}
}
@ -512,23 +625,44 @@ Polygons voronoi_offset(
double dmin = std::min(d0, d1);
double dmax = std::max(d0, d1);
bool has_intersection = false;
bool possibly_two_points = false;
if (offset_distance2 <= dmax) {
if (offset_distance2 >= dmin) {
has_intersection = true;
} else {
double dmin_new;
double dmin_new = dmin;
if (point_vs_segment) {
Vec2d ft = foot_pt(cell->contains_segment() ? line0 : line1, pt0);
// Project on the source segment.
const Line &line = cell->contains_segment() ? line0 : line1;
const Vec2d pt_line = line.a.cast<double>();
const Vec2d v_line = (line.b - line.a).cast<double>();
double t0 = (p0 - pt_line).dot(v_line);
double t1 = (p1 - pt_line).dot(v_line);
double tx = (px - pt_line).dot(v_line);
if ((tx >= t0 && tx <= t1) || (tx >= t1 && tx <= t0)) {
// Projection of the Point site falls between the projections of the Voronoi edge end points
// onto the Line site.
Vec2d ft = pt_line + (tx / v_line.squaredNorm()) * v_line;
dmin_new = (ft - px).squaredNorm() * 0.25;
}
} else {
// point vs. point
const Point &pt1 = (cell2->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line1.a : line1.b;
dmin_new = (pt1.cast<double>() - px).squaredNorm() * 0.25;
// Point-Point Voronoi sites. Project point site onto the current Voronoi edge.
Vec2d v = p1 - p0;
auto l2 = v.squaredNorm();
assert(l2 > 0);
auto t = v.dot(px - p0);
if (t >= 0. && t <= l2) {
// Projection falls onto the Voronoi edge. Calculate foot point and distance.
Vec2d ft = p0 + (t / l2) * v;
dmin_new = (ft - px).squaredNorm();
}
}
assert(dmin_new < dmax + SCALED_EPSILON);
assert(dmin_new < dmin + SCALED_EPSILON);
if (dmin_new < dmin) {
dmin = dmin_new;
has_intersection = offset_distance2 >= dmin;
has_intersection = possibly_two_points = offset_distance2 >= dmin;
}
}
}
if (has_intersection) {
@ -540,9 +674,13 @@ Polygons voronoi_offset(
const Point &pt1 = (cell2->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line1.a : line1.b;
intersections = detail::point_point_equal_distance_points(pt0, pt1, offset_distance);
}
// If the span of distances of start / end point / foot point to the point site indicate an intersection,
// we should find one.
assert(intersections.count > 0);
if (intersections.count == 2) {
// Now decide which points fall on this Voronoi edge.
// Tangential points (single intersection) are ignored.
if (possibly_two_points) {
Vec2d v = p1 - p0;
double l2 = v.squaredNorm();
double t0 = v.dot(intersections.pts[0] - p0);
@ -562,45 +700,64 @@ Polygons voronoi_offset(
}
} else if (t1 < 0. || t1 > l2)
-- intersections.count;
} else {
// Take the point furthest from the end points of the Voronoi edge or a Voronoi parabolic arc.
double d0 = std::max((intersections.pts[0] - p0).squaredNorm(), (intersections.pts[0] - p1).squaredNorm());
double d1 = std::max((intersections.pts[1] - p0).squaredNorm(), (intersections.pts[1] - p1).squaredNorm());
if (d0 > d1)
intersections.pts[0] = intersections.pts[1];
-- intersections.count;
}
assert(intersections.count > 0);
if (intersections.count == 2) {
edge_candidate[edge_idx] = edge_candidate[edge_idx2] = 3;
edge_offset_point[edge_idx] = intersections.pts[0];
edge_offset_point[edge_idx2] = intersections.pts[1];
set_edge_state_final(edge_idx, EdgeState::Active);
set_edge_state_final(edge_idx2, EdgeState::Active);
edge_offset_point[edge_idx] = intersections.pts[1];
edge_offset_point[edge_idx2] = intersections.pts[0];
done = true;
} else if (intersections.count == 1) {
if (d1 > d0) {
if (d1 < d0)
std::swap(edge_idx, edge_idx2);
edge_candidate[edge_idx] = 3;
edge_candidate[edge_idx2] = 0;
set_edge_state_final(edge_idx, EdgeState::Active);
set_edge_state_final(edge_idx2, EdgeState::Inactive);
edge_offset_point[edge_idx] = intersections.pts[0];
}
done = true;
}
}
if (! done)
edge_candidate[edge_idx] = edge_candidate[edge_idx2] = 0;
}
}
if (! done) {
set_edge_state_final(edge_idx, EdgeState::Inactive);
set_edge_state_final(edge_idx2, EdgeState::Inactive);
}
}
}
}
#ifndef NDEBUG
for (const VD::edge_type &edge : vd.edges()) {
assert(edge_state[&edge - front_edge] == EdgeState::Inactive || edge_state[&edge - front_edge] == EdgeState::Active);
// None of a new edge candidate may start with null vertex.
assert(edge_state[&edge - front_edge] == EdgeState::Inactive || edge.vertex0() != nullptr);
assert(edge_state[edge.twin() - front_edge] == EdgeState::Inactive || edge.twin()->vertex0() != nullptr);
}
#endif // NDEBUG
#ifdef VORONOI_DEBUG_OUT
{
Lines helper_lines;
for (const VD::edge_type &edge : vd.edges())
if (edge_candidate[&edge - front_edge] == 3)
if (edge_state[&edge - front_edge] == EdgeState::Active)
helper_lines.emplace_back(Line(Point(edge.vertex0()->x(), edge.vertex0()->y()), Point(edge_offset_point[&edge - front_edge].cast<coord_t>())));
dump_voronoi_to_svg(debug_out_path("voronoi-offset-candidates2.svg").c_str(), vd, Points(), lines, Polygons(), helper_lines);
dump_voronoi_to_svg(debug_out_path("voronoi-offset-candidates2-%d.svg", irun).c_str(), vd, Points(), lines, Polygons(), helper_lines);
}
#endif // VORONOI_DEBUG_OUT
auto next_offset_edge = [&edge_candidate, front_edge](const VD::edge_type *start_edge) -> const VD::edge_type* {
auto next_offset_edge = [&edge_state, front_edge](const VD::edge_type *start_edge) -> const VD::edge_type* {
for (const VD::edge_type *edge = start_edge->next(); edge != start_edge; edge = edge->next())
if (edge_candidate[edge->twin() - front_edge] == 3)
if (edge_state[edge->twin() - front_edge] == EdgeState::Active)
return edge->twin();
assert(false);
// assert(false);
return nullptr;
};
@ -609,56 +766,66 @@ Polygons voronoi_offset(
const Line &line = lines[cell.source_index()];
return cell.contains_point() ?
(((cell.source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line.a : line.b).cast<double>() - point).norm() :
line.distance_to(point.cast<coord_t>());
(Geometry::foot_pt<Vec2d>(line.a.cast<double>(), (line.b - line.a).cast<double>(), point) - point).norm();
};
#endif /* NDEBUG */
// Track the offset curves.
Polygons out;
double angle_step = 2. * acos((offset_distance - discretization_error) / offset_distance);
double sin_threshold = sin(angle_step) + EPSILON;
double cos_threshold = cos(angle_step);
for (size_t seed_edge_idx = 0; seed_edge_idx < vd.num_edges(); ++ seed_edge_idx)
if (edge_candidate[seed_edge_idx] == 3) {
if (edge_state[seed_edge_idx] == EdgeState::Active) {
const VD::edge_type *start_edge = &vd.edges()[seed_edge_idx];
const VD::edge_type *edge = start_edge;
Polygon poly;
do {
// find the next edge
const VD::edge_type *next_edge = next_offset_edge(edge);
#ifdef VORONOI_DEBUG_OUT
if (next_edge == nullptr) {
Lines helper_lines;
dump_voronoi_to_svg(debug_out_path("voronoi-offset-open-loop-%d.svg", irun).c_str(), vd, Points(), lines, Polygons(), to_lines(poly));
}
#endif // VORONOI_DEBUG_OUT
assert(next_edge);
//std::cout << "offset-output: "; print_edge(edge); std::cout << " to "; print_edge(next_edge); std::cout << "\n";
// Interpolate a circular segment or insert a linear segment between edge and next_edge.
const VD::cell_type *cell = edge->cell();
edge_candidate[next_edge - front_edge] = 0;
edge_state[next_edge - front_edge] = EdgeState::Inactive;
Vec2d p1 = edge_offset_point[edge - front_edge];
Vec2d p2 = edge_offset_point[next_edge - front_edge];
#ifndef NDEBUG
{
double err = dist_to_site(*cell, p1) - offset_distance;
double err2 = dist_to_site(*cell, p2) - offset_distance;
#ifdef VORONOI_DEBUG_OUT
if (std::max(err, err2) >= SCALED_EPSILON) {
Lines helper_lines;
dump_voronoi_to_svg(debug_out_path("voronoi-offset-incorrect_pt-%d.svg", irun).c_str(), vd, Points(), lines, Polygons(), to_lines(poly));
}
#endif // VORONOI_DEBUG_OUT
assert(std::abs(err) < SCALED_EPSILON);
err = dist_to_site(*cell, p2) - offset_distance;
assert(std::abs(err) < SCALED_EPSILON);
assert(std::abs(err2) < SCALED_EPSILON);
}
#endif /* NDEBUG */
if (cell->contains_point()) {
// Discretize an arc from p1 to p2 with radius = offset_distance and discretization_error.
// The arc should cover angle < PI.
//FIXME we should be able to produce correctly oriented output curves based on the first edge taken!
// The extracted contour is CCW oriented, extracted holes are CW oriented.
// The extracted arc will have the same orientation. As the Voronoi regions are convex, the angle covered by the arc will be convex as well.
const Line &line0 = lines[cell->source_index()];
const Vec2d &center = ((cell->source_category() == boost::polygon::SOURCE_CATEGORY_SEGMENT_START_POINT) ? line0.a : line0.b).cast<double>();
const Vec2d v1 = p1 - center;
const Vec2d v2 = p2 - center;
double orient = cross2(v1, v2);
double orient_norm = v1.norm() * v2.norm();
bool ccw = orient > 0;
bool obtuse = v1.dot(v2) < 0.;
if (! ccw)
orient = - orient;
assert(orient != 0.);
if (obtuse || orient > orient_norm * sin_threshold) {
bool ccw = cross2(v1, v2) > 0;
double cos_a = v1.dot(v2);
double norm = v1.norm() * v2.norm();
assert(norm > 0.);
if (cos_a < cos_threshold * norm) {
// Angle is bigger than the threshold, therefore the arc will be discretized.
double angle = asin(orient / orient_norm);
if (obtuse)
angle = M_PI - angle;
cos_a /= norm;
assert(cos_a > -1. - EPSILON && cos_a < 1. + EPSILON);
double angle = acos(std::max(-1., std::min(1., cos_a)));
size_t n_steps = size_t(ceil(angle / angle_step));
double astep = angle / n_steps;
if (! ccw)
@ -672,7 +839,11 @@ Polygons voronoi_offset(
}
}
}
poly.points.emplace_back(Point(coord_t(p2.x()), coord_t(p2.y())));
{
Point pt_last(coord_t(p2.x()), coord_t(p2.y()));
if (poly.empty() || poly.points.back() != pt_last)
poly.points.emplace_back(pt_last);
}
edge = next_edge;
} while (edge != start_edge);
out.emplace_back(std::move(poly));

View File

@ -305,44 +305,52 @@ static inline void dump_voronoi_to_svg(
const Lines &lines,
const Polygons &offset_curves = Polygons(),
const Lines &helper_lines = Lines(),
const double scale = 0.7) // 0.2?
double scale = 0)
{
const std::string inputSegmentPointColor = "lightseagreen";
const coord_t inputSegmentPointRadius = coord_t(0.09 * scale / SCALING_FACTOR);
const std::string inputSegmentColor = "lightseagreen";
const coord_t inputSegmentLineWidth = coord_t(0.03 * scale / SCALING_FACTOR);
const std::string voronoiPointColor = "black";
const coord_t voronoiPointRadius = coord_t(0.06 * scale / SCALING_FACTOR);
const std::string voronoiLineColorPrimary = "black";
const std::string voronoiLineColorSecondary = "green";
const std::string voronoiArcColor = "red";
const coord_t voronoiLineWidth = coord_t(0.02 * scale / SCALING_FACTOR);
const std::string offsetCurveColor = "magenta";
const coord_t offsetCurveLineWidth = coord_t(0.09 * scale / SCALING_FACTOR);
const std::string helperLineColor = "orange";
const coord_t helperLineWidth = coord_t(0.09 * scale / SCALING_FACTOR);
const bool internalEdgesOnly = false;
const bool primaryEdgesOnly = false;
BoundingBox bbox;
bbox.merge(get_extents(points));
bbox.merge(get_extents(lines));
bbox.merge(get_extents(offset_curves));
bbox.merge(get_extents(helper_lines));
bbox.min -= (0.01 * bbox.size().cast<double>()).cast<coord_t>();
bbox.max += (0.01 * bbox.size().cast<double>()).cast<coord_t>();
if (scale == 0)
scale =
// 0.1
0.01
* std::min(bbox.size().x(), bbox.size().y());
else
scale /= SCALING_FACTOR;
const std::string inputSegmentPointColor = "lightseagreen";
const coord_t inputSegmentPointRadius = coord_t(0.09 * scale);
const std::string inputSegmentColor = "lightseagreen";
const coord_t inputSegmentLineWidth = coord_t(0.03 * scale);
const std::string voronoiPointColor = "black";
const coord_t voronoiPointRadius = coord_t(0.06 * scale);
const std::string voronoiLineColorPrimary = "black";
const std::string voronoiLineColorSecondary = "green";
const std::string voronoiArcColor = "red";
const coord_t voronoiLineWidth = coord_t(0.02 * scale);
const std::string offsetCurveColor = "magenta";
const coord_t offsetCurveLineWidth = coord_t(0.02 * scale);
const std::string helperLineColor = "orange";
const coord_t helperLineWidth = coord_t(0.04 * scale);
const bool internalEdgesOnly = false;
const bool primaryEdgesOnly = false;
::Slic3r::SVG svg(path, bbox);
// bbox.scale(1.2);
// For clipping of half-lines to some reasonable value.
// The line will then be clipped by the SVG viewer anyway.
const double bbox_dim_max = double(std::max(bbox.size().x(), bbox.size().y()));
// For the discretization of the Voronoi parabolic segments.
const double discretization_step = 0.05 * bbox_dim_max;
const double discretization_step = 0.0002 * bbox_dim_max;
// Make a copy of the input segments with the double type.
std::vector<Voronoi::Internal::segment_type> segments;

View File

@ -73,13 +73,6 @@ inline std::string debug_out_path(const char *name, ...)
return std::string(SLIC3R_DEBUG_OUT_PATH_PREFIX) + std::string(buffer);
}
#ifdef _MSC_VER
// Visual Studio older than 2015 does not support the prinf type specifier %zu. Use %Iu instead.
#define PRINTF_ZU "%Iu"
#else
#define PRINTF_ZU "%zu"
#endif
#ifndef UNUSED
#define UNUSED(x) (void)(x)
#endif /* UNUSED */

View File

@ -1198,6 +1198,12 @@ TEST_CASE("Voronoi NaN coordinates 12139", "[Voronoi][!hide][!mayfail]")
#endif
}
struct OffsetTest {
double distance;
size_t num_outer;
size_t num_inner;
};
TEST_CASE("Voronoi offset", "[VoronoiOffset]")
{
Polygons poly_with_hole = { Polygon {
@ -1210,23 +1216,180 @@ TEST_CASE("Voronoi offset", "[VoronoiOffset]")
}
};
double area = std::accumulate(poly_with_hole.begin(), poly_with_hole.end(), 0., [](double a, auto &poly){ return a + poly.area(); });
REQUIRE(area > 0.);
VD vd;
Lines lines = to_lines(poly_with_hole);
construct_voronoi(lines.begin(), lines.end(), &vd);
Polygons offsetted_polygons_out = voronoi_offset(vd, lines, scale_(0.2), scale_(0.005));
REQUIRE(offsetted_polygons_out.size() == 1);
for (const OffsetTest &ot : {
OffsetTest { scale_(0.2), 1, 1 },
OffsetTest { scale_(0.4), 1, 1 },
OffsetTest { scale_(0.5), 1, 1 },
OffsetTest { scale_(0.505), 1, 2 },
OffsetTest { scale_(0.51), 1, 2 },
OffsetTest { scale_(0.52), 1, 1 },
OffsetTest { scale_(0.53), 1, 1 },
OffsetTest { scale_(0.54), 1, 1 },
OffsetTest { scale_(0.55), 1, 0 }
}) {
Polygons offsetted_polygons_out = voronoi_offset(vd, lines, ot.distance, scale_(0.005));
REQUIRE(offsetted_polygons_out.size() == ot.num_outer);
#ifdef VORONOI_DEBUG_OUT
dump_voronoi_to_svg(debug_out_path("voronoi-offset-out.svg").c_str(),
dump_voronoi_to_svg(debug_out_path("voronoi-offset-out-%lf.svg", ot.distance).c_str(),
vd, Points(), lines, offsetted_polygons_out);
#endif
Polygons offsetted_polygons_in = voronoi_offset(vd, lines, - scale_(0.2), scale_(0.005));
REQUIRE(offsetted_polygons_in.size() == 1);
Polygons offsetted_polygons_in = voronoi_offset(vd, lines, - ot.distance, scale_(0.005));
REQUIRE(offsetted_polygons_in.size() == ot.num_inner);
#ifdef VORONOI_DEBUG_OUT
dump_voronoi_to_svg(debug_out_path("voronoi-offset-in.svg").c_str(),
dump_voronoi_to_svg(debug_out_path("voronoi-offset-in-%lf.svg", ot.distance).c_str(),
vd, Points(), lines, offsetted_polygons_in);
#endif
}
}
TEST_CASE("Voronoi offset 2", "[VoronoiOffset]")
{
coord_t mm = coord_t(scale_(1.));
Polygons poly = {
Polygon {
{ 0, 0 },
{ 1, 0 },
{ 1, 1 },
{ 2, 1 },
{ 2, 0 },
{ 3, 0 },
{ 3, 2 },
{ 0, 2 }
},
Polygon {
{ 0, - 1 - 2 },
{ 3, - 1 - 2 },
{ 3, - 1 - 0 },
{ 2, - 1 - 0 },
{ 2, - 1 - 1 },
{ 1, - 1 - 1 },
{ 1, - 1 - 0 },
{ 0, - 1 - 0 }
},
};
for (Polygon &p : poly)
for (Point &pt : p.points)
pt *= mm;
double area = std::accumulate(poly.begin(), poly.end(), 0., [](double a, auto &poly){ return a + poly.area(); });
REQUIRE(area > 0.);
VD vd;
Lines lines = to_lines(poly);
construct_voronoi(lines.begin(), lines.end(), &vd);
for (const OffsetTest &ot : {
OffsetTest { scale_(0.2), 2, 2 },
OffsetTest { scale_(0.4), 2, 2 },
OffsetTest { scale_(0.45), 2, 2 },
OffsetTest { scale_(0.48), 2, 2 },
//FIXME Exact intersections of an Offset curve with any Voronoi vertex are not handled correctly yet.
// OffsetTest { scale_(0.5), 2, 2 },
OffsetTest { scale_(0.505), 2, 4 },
OffsetTest { scale_(0.7), 2, 0 },
OffsetTest { scale_(0.8), 1, 0 }
}) {
Polygons offsetted_polygons_out = voronoi_offset(vd, lines, ot.distance, scale_(0.005));
#ifdef VORONOI_DEBUG_OUT
dump_voronoi_to_svg(debug_out_path("voronoi-offset2-out-%lf.svg", ot.distance).c_str(),
vd, Points(), lines, offsetted_polygons_out);
#endif
REQUIRE(offsetted_polygons_out.size() == ot.num_outer);
Polygons offsetted_polygons_in = voronoi_offset(vd, lines, - ot.distance, scale_(0.005));
#ifdef VORONOI_DEBUG_OUT
dump_voronoi_to_svg(debug_out_path("voronoi-offset2-in-%lf.svg", ot.distance).c_str(),
vd, Points(), lines, offsetted_polygons_in);
#endif
REQUIRE(offsetted_polygons_in.size() == ot.num_inner);
}
}
TEST_CASE("Voronoi offset 3", "[VoronoiOffset]")
{
coord_t mm = coord_t(scale_(1.));
Polygons poly = {
Polygon {
{ 0, 0 },
{ 2, 0 },
{ 2, 1 },
{ 3, 1 },
{ 3, 0 },
{ 5, 0 },
{ 5, 2 },
{ 4, 2 },
{ 4, 3 },
{ 1, 3 },
{ 1, 2 },
{ 0, 2 }
},
Polygon {
{ 0, -1 - 2 },
{ 1, -1 - 2 },
{ 1, -1 - 3 },
{ 4, -1 - 3 },
{ 4, -1 - 2 },
{ 5, -1 - 2 },
{ 5, -1 - 0 },
{ 3, -1 - 0 },
{ 3, -1 - 1 },
{ 2, -1 - 1 },
{ 2, -1 - 0 },
{ 0, -1 - 0 }
},
};
for (Polygon &p : poly) {
REQUIRE(p.area() > 0.);
for (Point &pt : p.points)
pt *= mm;
}
VD vd;
Lines lines = to_lines(poly);
construct_voronoi(lines.begin(), lines.end(), &vd);
for (const OffsetTest &ot : {
OffsetTest { scale_(0.2), 2, 2 },
OffsetTest { scale_(0.4), 2, 2 },
OffsetTest { scale_(0.49), 2, 2 },
//FIXME this fails
// OffsetTest { scale_(0.5), 2, 2 },
OffsetTest { scale_(0.51), 2, 2 },
OffsetTest { scale_(0.56), 2, 2 },
OffsetTest { scale_(0.6), 2, 2 },
OffsetTest { scale_(0.7), 2, 2 },
OffsetTest { scale_(0.8), 1, 6 },
OffsetTest { scale_(0.9), 1, 6 },
OffsetTest { scale_(0.99), 1, 6 },
//FIXME this fails
// OffsetTest { scale_(1.0), 1, 6 },
OffsetTest { scale_(1.01), 1, 0 },
}) {
Polygons offsetted_polygons_out = voronoi_offset(vd, lines, ot.distance, scale_(0.005));
#ifdef VORONOI_DEBUG_OUT
dump_voronoi_to_svg(debug_out_path("voronoi-offset2-out-%lf.svg", ot.distance).c_str(),
vd, Points(), lines, offsetted_polygons_out);
#endif
REQUIRE(offsetted_polygons_out.size() == ot.num_outer);
Polygons offsetted_polygons_in = voronoi_offset(vd, lines, - ot.distance, scale_(0.005));
#ifdef VORONOI_DEBUG_OUT
dump_voronoi_to_svg(debug_out_path("voronoi-offset2-in-%lf.svg", ot.distance).c_str(),
vd, Points(), lines, offsetted_polygons_in);
#endif
REQUIRE(offsetted_polygons_in.size() == ot.num_inner);
}
}