static Polylines make_gyroid_waves(double gridZ, double density_adjusted, double line_spacing, double width, double height)
{
const double scaleFactor = scale_(line_spacing) / density_adjusted;
//scale factor for 5% : 8 712 388
// 1z = 10^-6 mm ?
const double z = gridZ / scaleFactor;
const double z_sin = sin(z);
const double z_cos = cos(z);
bool vertical = (std::abs(z_sin) <= std::abs(z_cos));
double lower_bound = 0.;
double upper_bound = height;
bool flip = true;
if (vertical) {
flip = false;
lower_bound = -M_PI;
upper_bound = width - M_PI_2;
std::swap(width,height);
}
std::vector<Vec2d> one_period = make_one_period(width, scaleFactor, z_cos, z_sin, vertical, flip); // creates one period of the waves, so it doesn't have to be recalculated all the time
Polylines result;
for (double y0 = lower_bound; y0 < upper_bound+EPSILON; y0 += 2*M_PI) // creates odd polylines
result.emplace_back(make_wave(one_period, width, height, y0, scaleFactor, z_cos, z_sin, vertical));
flip = !flip; // even polylines are a bit shifted
one_period = make_one_period(width, scaleFactor, z_cos, z_sin, vertical, flip); // updates the one period sample
for (double y0 = lower_bound + M_PI; y0 < upper_bound+EPSILON; y0 += 2*M_PI) // creates even polylines
result.emplace_back(make_wave(one_period, width, height, y0, scaleFactor, z_cos, z_sin, vertical));
return result;
}
static Polylines make_gyroid_waves(double gridZ, double density, double layer_width, double width, double height)
{
double scaleFactor = scale_(layer_width) / density;
double segmentSize = 0.5 * density;
//scale factor for 5% : 8 712 388
// 1z = 10^-6 mm ?
double z = gridZ / scaleFactor;
double z_sin = sin(z);
double z_cos = cos(z);
Polylines result;
if (abs(z_sin) <= abs(z_cos)) {
// Vertical wave
double x0 = M_PI * (int)((- 0.5 * M_PI) / M_PI - 1.);
bool flip = ((int)(x0 / M_PI + 1.) & 1) != 0;
for (; x0 < width - 0.5 * M_PI; x0 += M_PI, flip = ! flip)
result.emplace_back(make_wave_vertical(width, height, x0, segmentSize, scaleFactor, z_cos, z_sin, flip));
} else {
// Horizontal wave
bool flip = true;
for (double y0 = 0.; y0 < width; y0 += M_PI, flip = !flip)
result.emplace_back(make_wave_horizontal(width, height, y0, segmentSize, scaleFactor, z_cos, z_sin, flip));
}
return result;
}
Polylines _clipper_pl(ClipperLib::ClipType clipType, const Polygons &subject, const Polygons &clip, bool safety_offset_)
{
// transform input polygons into polylines
Polylines polylines;
polylines.reserve(subject.size());
for (Polygons::const_iterator polygon = subject.begin(); polygon != subject.end(); ++polygon)
polylines.emplace_back(polygon->operator Polyline()); // implicit call to split_at_first_point()
// perform clipping
Polylines retval = _clipper_pl(clipType, polylines, clip, safety_offset_);
/* If the split_at_first_point() call above happens to split the polygon inside the clipping area
we would get two consecutive polylines instead of a single one, so we go through them in order
to recombine continuous polylines. */
for (size_t i = 0; i < retval.size(); ++i) {
for (size_t j = i+1; j < retval.size(); ++j) {
if (retval[i].points.back() == retval[j].points.front()) {
/* If last point of i coincides with first point of j,
append points of j to i and delete j */
retval[i].points.insert(retval[i].points.end(), retval[j].points.begin()+1, retval[j].points.end());
retval.erase(retval.begin() + j);
--j;
} else if (retval[i].points.front() == retval[j].points.back()) {
/* If first point of i coincides with last point of j,
prepend points of j to i and delete j */
retval[i].points.insert(retval[i].points.begin(), retval[j].points.begin(), retval[j].points.end()-1);
retval.erase(retval.begin() + j);
--j;
} else if (retval[i].points.front() == retval[j].points.front()) {
/* Since Clipper does not preserve orientation of polylines,
also check the case when first point of i coincides with first point of j. */
retval[j].reverse();
retval[i].points.insert(retval[i].points.begin(), retval[j].points.begin(), retval[j].points.end()-1);
retval.erase(retval.begin() + j);
--j;
} else if (retval[i].points.back() == retval[j].points.back()) {
/* Since Clipper does not preserve orientation of polylines,
also check the case when last point of i coincides with last point of j. */
retval[j].reverse();
retval[i].points.insert(retval[i].points.end(), retval[j].points.begin()+1, retval[j].points.end());
retval.erase(retval.begin() + j);
--j;
}
}
}
return retval;
}
Lines
_clipper_ln(ClipperLib::ClipType clipType, const Lines &subject, const Polygons &clip,
bool safety_offset_)
{
// convert Lines to Polylines
Polylines polylines;
polylines.reserve(subject.size());
for (const Line &line : subject)
polylines.emplace_back(Polyline(line.a, line.b));
// perform operation
polylines = _clipper_pl(clipType, polylines, clip, safety_offset_);
// convert Polylines to Lines
Lines retval;
for (Polylines::const_iterator polyline = polylines.begin(); polyline != polylines.end(); ++polyline)
retval.emplace_back(polyline->operator Line());
return retval;
}
void FillGyroid::_fill_surface_single(
const FillParams ¶ms,
unsigned int thickness_layers,
const std::pair<float, Point> &direction,
ExPolygon &expolygon,
Polylines &polylines_out)
{
// no rotation is supported for this infill pattern
BoundingBox bb = expolygon.contour.bounding_box();
coord_t distance = coord_t(scale_(this->spacing) / (params.density*this->scaling));
// align bounding box to a multiple of our grid module
bb.merge(_align_to_grid(bb.min, Point(2*M_PI*distance, 2*M_PI*distance)));
// generate pattern
Polylines polylines = make_gyroid_waves(
scale_(this->z),
params.density*this->scaling,
this->spacing,
ceil(bb.size().x / distance) + 1.,
ceil(bb.size().y / distance) + 1.);
// move pattern in place
for (Polyline &polyline : polylines)
polyline.translate(bb.min.x, bb.min.y);
// clip pattern to boundaries
polylines = intersection_pl(polylines, (Polygons)expolygon);
// connect lines
if (! params.dont_connect && ! polylines.empty()) { // prevent calling leftmost_point() on empty collections
ExPolygon expolygon_off;
{
ExPolygons expolygons_off = offset_ex(expolygon, (float)SCALED_EPSILON);
if (! expolygons_off.empty()) {
// When expanding a polygon, the number of islands could only shrink. Therefore the offset_ex shall generate exactly one expanded island for one input island.
assert(expolygons_off.size() == 1);
std::swap(expolygon_off, expolygons_off.front());
}
}
Polylines chained = PolylineCollection::chained_path_from(
std::move(polylines),
PolylineCollection::leftmost_point(polylines), false); // reverse allowed
bool first = true;
for (Polyline &polyline : chained) {
if (! first) {
// Try to connect the lines.
Points &pts_end = polylines_out.back().points;
const Point &first_point = polyline.points.front();
const Point &last_point = pts_end.back();
// TODO: we should also check that both points are on a fill_boundary to avoid
// connecting paths on the boundaries of internal regions
// TODO: avoid crossing current infill path
if (first_point.distance_to(last_point) <= 5 * distance &&
expolygon_off.contains(Line(last_point, first_point))) {
// Append the polyline.
pts_end.insert(pts_end.end(), polyline.points.begin(), polyline.points.end());
continue;
}
}
// The lines cannot be connected.
polylines_out.emplace_back(std::move(polyline));
first = false;
}
}
}