PrusaSlicer/src/libslic3r/GCode/SeamPlacer.cpp

796 lines
32 KiB
C++

#include "SeamPlacer.hpp"
#include "libslic3r/ExtrusionEntity.hpp"
#include "libslic3r/Print.hpp"
#include "libslic3r/BoundingBox.hpp"
#include "libslic3r/EdgeGrid.hpp"
#include "libslic3r/ClipperUtils.hpp"
#include "libslic3r/SVG.hpp"
#include "libslic3r/Layer.hpp"
namespace Slic3r {
// This penalty is added to all points inside custom blockers (subtracted from pts inside enforcers).
static constexpr float ENFORCER_BLOCKER_PENALTY = 100;
// In case there are custom enforcers/blockers, the loop polygon shall always have
// sides smaller than this (so it isn't limited to original resolution).
static constexpr float MINIMAL_POLYGON_SIDE = scale_(0.2f);
// When spAligned is active and there is a support enforcer,
// add this penalty to its center.
static constexpr float ENFORCER_CENTER_PENALTY = -10.f;
static float extrudate_overlap_penalty(float nozzle_r, float weight_zero, float overlap_distance)
{
// The extrudate is not fully supported by the lower layer. Fit a polynomial penalty curve.
// Solved by sympy package:
/*
from sympy import *
(x,a,b,c,d,r,z)=symbols('x a b c d r z')
p = a + b*x + c*x*x + d*x*x*x
p2 = p.subs(solve([p.subs(x, -r), p.diff(x).subs(x, -r), p.diff(x,x).subs(x, -r), p.subs(x, 0)-z], [a, b, c, d]))
from sympy.plotting import plot
plot(p2.subs(r,0.2).subs(z,1.), (x, -1, 3), adaptive=False, nb_of_points=400)
*/
if (overlap_distance < - nozzle_r) {
// The extrudate is fully supported by the lower layer. This is the ideal case, therefore zero penalty.
return 0.f;
} else {
float x = overlap_distance / nozzle_r;
float x2 = x * x;
float x3 = x2 * x;
return weight_zero * (1.f + 3.f * x + 3.f * x2 + x3);
}
}
// Return a value in <0, 1> of a cubic B-spline kernel centered around zero.
// The B-spline is re-scaled so it has value 1 at zero.
static inline float bspline_kernel(float x)
{
x = std::abs(x);
if (x < 1.f) {
return 1.f - (3.f / 2.f) * x * x + (3.f / 4.f) * x * x * x;
}
else if (x < 2.f) {
x -= 1.f;
float x2 = x * x;
float x3 = x2 * x;
return (1.f / 4.f) - (3.f / 4.f) * x + (3.f / 4.f) * x2 - (1.f / 4.f) * x3;
}
else
return 0;
}
static Points::const_iterator project_point_to_polygon_and_insert(Polygon &polygon, const Point &pt, double eps)
{
assert(polygon.points.size() >= 2);
if (polygon.points.size() <= 1)
if (polygon.points.size() == 1)
return polygon.points.begin();
Point pt_min;
double d_min = std::numeric_limits<double>::max();
size_t i_min = size_t(-1);
for (size_t i = 0; i < polygon.points.size(); ++ i) {
size_t j = i + 1;
if (j == polygon.points.size())
j = 0;
const Point &p1 = polygon.points[i];
const Point &p2 = polygon.points[j];
const Slic3r::Point v_seg = p2 - p1;
const Slic3r::Point v_pt = pt - p1;
const int64_t l2_seg = int64_t(v_seg(0)) * int64_t(v_seg(0)) + int64_t(v_seg(1)) * int64_t(v_seg(1));
int64_t t_pt = int64_t(v_seg(0)) * int64_t(v_pt(0)) + int64_t(v_seg(1)) * int64_t(v_pt(1));
if (t_pt < 0) {
// Closest to p1.
double dabs = sqrt(int64_t(v_pt(0)) * int64_t(v_pt(0)) + int64_t(v_pt(1)) * int64_t(v_pt(1)));
if (dabs < d_min) {
d_min = dabs;
i_min = i;
pt_min = p1;
}
}
else if (t_pt > l2_seg) {
// Closest to p2. Then p2 is the starting point of another segment, which shall be discovered in the next step.
continue;
} else {
// Closest to the segment.
assert(t_pt >= 0 && t_pt <= l2_seg);
int64_t d_seg = int64_t(v_seg(1)) * int64_t(v_pt(0)) - int64_t(v_seg(0)) * int64_t(v_pt(1));
double d = double(d_seg) / sqrt(double(l2_seg));
double dabs = std::abs(d);
if (dabs < d_min) {
d_min = dabs;
i_min = i;
// Evaluate the foot point.
pt_min = p1;
double linv = double(d_seg) / double(l2_seg);
pt_min(0) = pt(0) - coord_t(floor(double(v_seg(1)) * linv + 0.5));
pt_min(1) = pt(1) + coord_t(floor(double(v_seg(0)) * linv + 0.5));
assert(Line(p1, p2).distance_to(pt_min) < scale_(1e-5));
}
}
}
assert(i_min != size_t(-1));
if ((pt_min - polygon.points[i_min]).cast<double>().norm() > eps) {
// Insert a new point on the segment i_min, i_min+1.
return polygon.points.insert(polygon.points.begin() + (i_min + 1), pt_min);
}
return polygon.points.begin() + i_min;
}
static std::vector<float> polygon_angles_at_vertices(const Polygon &polygon, const std::vector<float> &lengths, float min_arm_length)
{
assert(polygon.points.size() + 1 == lengths.size());
if (min_arm_length > 0.25f * lengths.back())
min_arm_length = 0.25f * lengths.back();
// Find the initial prev / next point span.
size_t idx_prev = polygon.points.size();
size_t idx_curr = 0;
size_t idx_next = 1;
while (idx_prev > idx_curr && lengths.back() - lengths[idx_prev] < min_arm_length)
-- idx_prev;
while (idx_next < idx_prev && lengths[idx_next] < min_arm_length)
++ idx_next;
std::vector<float> angles(polygon.points.size(), 0.f);
for (; idx_curr < polygon.points.size(); ++ idx_curr) {
// Move idx_prev up until the distance between idx_prev and idx_curr is lower than min_arm_length.
if (idx_prev >= idx_curr) {
while (idx_prev < polygon.points.size() && lengths.back() - lengths[idx_prev] + lengths[idx_curr] > min_arm_length)
++ idx_prev;
if (idx_prev == polygon.points.size())
idx_prev = 0;
}
while (idx_prev < idx_curr && lengths[idx_curr] - lengths[idx_prev] > min_arm_length)
++ idx_prev;
// Move idx_prev one step back.
if (idx_prev == 0)
idx_prev = polygon.points.size() - 1;
else
-- idx_prev;
// Move idx_next up until the distance between idx_curr and idx_next is greater than min_arm_length.
if (idx_curr <= idx_next) {
while (idx_next < polygon.points.size() && lengths[idx_next] - lengths[idx_curr] < min_arm_length)
++ idx_next;
if (idx_next == polygon.points.size())
idx_next = 0;
}
while (idx_next < idx_curr && lengths.back() - lengths[idx_curr] + lengths[idx_next] < min_arm_length)
++ idx_next;
// Calculate angle between idx_prev, idx_curr, idx_next.
const Point &p0 = polygon.points[idx_prev];
const Point &p1 = polygon.points[idx_curr];
const Point &p2 = polygon.points[idx_next];
const Point v1 = p1 - p0;
const Point v2 = p2 - p1;
int64_t dot = int64_t(v1(0))*int64_t(v2(0)) + int64_t(v1(1))*int64_t(v2(1));
int64_t cross = int64_t(v1(0))*int64_t(v2(1)) - int64_t(v1(1))*int64_t(v2(0));
float angle = float(atan2(double(cross), double(dot)));
angles[idx_curr] = angle;
}
return angles;
}
void SeamPlacer::init(const Print& print)
{
m_enforcers.clear();
m_blockers.clear();
m_seam_history.clear();
m_po_list.clear();
const std::vector<double>& nozzle_dmrs = print.config().nozzle_diameter.values;
float max_nozzle_dmr = *std::max_element(nozzle_dmrs.begin(), nozzle_dmrs.end());
std::vector<ExPolygons> temp_enf;
std::vector<ExPolygons> temp_blk;
for (const PrintObject* po : print.objects()) {
temp_enf.clear();
temp_blk.clear();
po->project_and_append_custom_facets(true, EnforcerBlockerType::ENFORCER, temp_enf);
po->project_and_append_custom_facets(true, EnforcerBlockerType::BLOCKER, temp_blk);
// Offset the triangles out slightly.
for (auto* custom_per_object : {&temp_enf, &temp_blk})
for (ExPolygons& explgs : *custom_per_object)
explgs = Slic3r::offset_ex(explgs, scale_(max_nozzle_dmr));
// FIXME: Offsetting should be done somehow cheaper, but following does not work
// for (auto* custom_per_object : {&temp_enf, &temp_blk}) {
// for (ExPolygons& plgs : *custom_per_object) {
// for (ExPolygon& plg : plgs) {
// auto out = Slic3r::offset_ex(plg, scale_(max_nozzle_dmr));
// plg = out.empty() ? ExPolygon() : out.front();
// assert(out.empty() || out.size() == 1);
// }
// }
// }
// Remember this PrintObject and initialize a store of enforcers and blockers for it.
m_po_list.push_back(po);
size_t po_idx = m_po_list.size() - 1;
m_enforcers.emplace_back(std::vector<CustomTrianglesPerLayer>(temp_enf.size()));
m_blockers.emplace_back(std::vector<CustomTrianglesPerLayer>(temp_blk.size()));
// A helper class to store data to build the AABB tree from.
class CustomTriangleRef {
public:
CustomTriangleRef(size_t idx,
Point&& centroid,
BoundingBox&& bb)
: m_idx{idx}, m_centroid{centroid},
m_bbox{AlignedBoxType(bb.min, bb.max)}
{}
size_t idx() const { return m_idx; }
const Point& centroid() const { return m_centroid; }
const TreeType::BoundingBox& bbox() const { return m_bbox; }
private:
size_t m_idx;
Point m_centroid;
AlignedBoxType m_bbox;
};
// A lambda to extract the ExPolygons and save them into the member AABB tree.
// Will be called for enforcers and blockers separately.
auto add_custom = [](std::vector<ExPolygons>& src, std::vector<CustomTrianglesPerLayer>& dest) {
// Go layer by layer, and append all the ExPolygons into the AABB tree.
size_t layer_idx = 0;
for (ExPolygons& expolys_on_layer : src) {
CustomTrianglesPerLayer& layer_data = dest[layer_idx];
std::vector<CustomTriangleRef> triangles_data;
layer_data.polys.reserve(expolys_on_layer.size());
triangles_data.reserve(expolys_on_layer.size());
for (ExPolygon& expoly : expolys_on_layer) {
if (expoly.empty())
continue;
layer_data.polys.emplace_back(std::move(expoly));
triangles_data.emplace_back(layer_data.polys.size() - 1,
layer_data.polys.back().centroid(),
layer_data.polys.back().bounding_box());
}
// All polygons are saved, build the AABB tree for them.
layer_data.tree.build(std::move(triangles_data));
++layer_idx;
}
};
add_custom(temp_enf, m_enforcers.at(po_idx));
add_custom(temp_blk, m_blockers.at(po_idx));
}
}
Point SeamPlacer::get_seam(const Layer& layer, const SeamPosition seam_position,
const ExtrusionLoop& loop, Point last_pos, coordf_t nozzle_dmr,
const PrintObject* po, bool was_clockwise, const EdgeGrid::Grid* lower_layer_edge_grid)
{
Polygon polygon = loop.polygon();
BoundingBox polygon_bb = polygon.bounding_box();
const coord_t nozzle_r = coord_t(scale_(0.5 * nozzle_dmr) + 0.5);
size_t po_idx = std::find(m_po_list.begin(), m_po_list.end(), po) - m_po_list.begin();
// Find current layer in respective PrintObject. Cache the result so the
// lookup is only done once per layer, not for each loop.
const Layer* layer_po = nullptr;
if (po == m_last_po && layer.print_z == m_last_print_z)
layer_po = m_last_layer_po;
else {
layer_po = po->get_layer_at_printz(layer.print_z);
m_last_po = po;
m_last_print_z = layer.print_z;
m_last_layer_po = layer_po;
}
if (! layer_po)
return last_pos;
// Index of this layer in the respective PrintObject.
size_t layer_idx = layer_po->id() - po->layers().front()->id(); // raft layers
assert(layer_idx < po->layer_count());
if (this->is_custom_seam_on_layer(layer_idx, po_idx)) {
// Seam enf/blockers can begin and end in between the original vertices.
// Let add extra points in between and update the leghths.
polygon.densify(MINIMAL_POLYGON_SIDE);
}
if (seam_position != spRandom) {
// Retrieve the last start position for this object.
float last_pos_weight = 1.f;
if (seam_position == spAligned) {
// Seam is aligned to the seam at the preceding layer.
if (po != nullptr) {
std::optional<Point> pos = m_seam_history.get_last_seam(m_po_list[po_idx], layer_idx, polygon_bb);
if (pos.has_value()) {
last_pos = *pos;
last_pos_weight = is_custom_enforcer_on_layer(layer_idx, po_idx) ? 0.f : 1.f;
}
}
}
else if (seam_position == spRear) {
// Object is centered around (0,0) in its current coordinate system.
last_pos.x() = 0;
last_pos.y() += coord_t(3. * po->bounding_box().radius());
last_pos_weight = 5.f;
} if (seam_position == spNearest) {
// last_pos already contains current nozzle position
}
// Insert a projection of last_pos into the polygon.
size_t last_pos_proj_idx;
{
auto it = project_point_to_polygon_and_insert(polygon, last_pos, 0.1 * nozzle_r);
last_pos_proj_idx = it - polygon.points.begin();
}
// Parametrize the polygon by its length.
std::vector<float> lengths = polygon.parameter_by_length();
// For each polygon point, store a penalty.
// First calculate the angles, store them as penalties. The angles are caluculated over a minimum arm length of nozzle_r.
std::vector<float> penalties = polygon_angles_at_vertices(polygon, lengths, float(nozzle_r));
// No penalty for reflex points, slight penalty for convex points, high penalty for flat surfaces.
const float penaltyConvexVertex = 1.f;
const float penaltyFlatSurface = 5.f;
const float penaltyOverhangHalf = 10.f;
// Penalty for visible seams.
for (size_t i = 0; i < polygon.points.size(); ++ i) {
float ccwAngle = penalties[i];
if (was_clockwise)
ccwAngle = - ccwAngle;
float penalty = 0;
if (ccwAngle <- float(0.6 * PI))
// Sharp reflex vertex. We love that, it hides the seam perfectly.
penalty = 0.f;
else if (ccwAngle > float(0.6 * PI))
// Seams on sharp convex vertices are more visible than on reflex vertices.
penalty = penaltyConvexVertex;
else if (ccwAngle < 0.f) {
// Interpolate penalty between maximum and zero.
penalty = penaltyFlatSurface * bspline_kernel(ccwAngle * float(PI * 2. / 3.));
} else {
assert(ccwAngle >= 0.f);
// Interpolate penalty between maximum and the penalty for a convex vertex.
penalty = penaltyConvexVertex + (penaltyFlatSurface - penaltyConvexVertex) * bspline_kernel(ccwAngle * float(PI * 2. / 3.));
}
// Give a negative penalty for points close to the last point or the prefered seam location.
float dist_to_last_pos_proj = (i < last_pos_proj_idx) ?
std::min(lengths[last_pos_proj_idx] - lengths[i], lengths.back() - lengths[last_pos_proj_idx] + lengths[i]) :
std::min(lengths[i] - lengths[last_pos_proj_idx], lengths.back() - lengths[i] + lengths[last_pos_proj_idx]);
float dist_max = 0.1f * lengths.back(); // 5.f * nozzle_dmr
penalty -= last_pos_weight * bspline_kernel(dist_to_last_pos_proj / dist_max);
penalties[i] = std::max(0.f, penalty);
}
// Penalty for overhangs.
if (lower_layer_edge_grid) {
// Use the edge grid distance field structure over the lower layer to calculate overhangs.
coord_t nozzle_r = coord_t(std::floor(scale_(0.5 * nozzle_dmr) + 0.5));
coord_t search_r = coord_t(std::floor(scale_(0.8 * nozzle_dmr) + 0.5));
for (size_t i = 0; i < polygon.points.size(); ++ i) {
const Point &p = polygon.points[i];
coordf_t dist;
// Signed distance is positive outside the object, negative inside the object.
// The point is considered at an overhang, if it is more than nozzle radius
// outside of the lower layer contour.
[[maybe_unused]] bool found = lower_layer_edge_grid->signed_distance(p, search_r, dist);
// If the approximate Signed Distance Field was initialized over lower_layer_edge_grid,
// then the signed distnace shall always be known.
assert(found);
penalties[i] += extrudate_overlap_penalty(float(nozzle_r), penaltyOverhangHalf, float(dist));
}
}
// Custom seam. Huge (negative) constant penalty is applied inside
// blockers (enforcers) to rule out points that should not win.
this->apply_custom_seam(polygon, po_idx, penalties, lengths, layer_idx, seam_position);
// Find a point with a minimum penalty.
size_t idx_min = std::min_element(penalties.begin(), penalties.end()) - penalties.begin();
if (seam_position != spAligned || ! is_custom_enforcer_on_layer(layer_idx, po_idx)) {
// Very likely the weight of idx_min is very close to the weight of last_pos_proj_idx.
// In that case use last_pos_proj_idx instead.
float penalty_aligned = penalties[last_pos_proj_idx];
float penalty_min = penalties[idx_min];
float penalty_diff_abs = std::abs(penalty_min - penalty_aligned);
float penalty_max = std::max(penalty_min, penalty_aligned);
float penalty_diff_rel = (penalty_max == 0.f) ? 0.f : penalty_diff_abs / penalty_max;
// printf("Align seams, penalty aligned: %f, min: %f, diff abs: %f, diff rel: %f\n", penalty_aligned, penalty_min, penalty_diff_abs, penalty_diff_rel);
if (std::abs(penalty_diff_rel) < 0.05) {
// Penalty of the aligned point is very close to the minimum penalty.
// Align the seams as accurately as possible.
idx_min = last_pos_proj_idx;
}
}
if (seam_position == spAligned && loop.role() == erExternalPerimeter)
m_seam_history.add_seam(po, polygon.points[idx_min], polygon_bb);
// Export the contour into a SVG file.
#if 0
{
static int iRun = 0;
SVG svg(debug_out_path("GCode_extrude_loop-%d.svg", iRun ++));
if (m_layer->lower_layer != NULL)
svg.draw(m_layer->lower_layer->slices);
for (size_t i = 0; i < loop.paths.size(); ++ i)
svg.draw(loop.paths[i].as_polyline(), "red");
Polylines polylines;
for (size_t i = 0; i < loop.paths.size(); ++ i)
polylines.push_back(loop.paths[i].as_polyline());
Slic3r::Polygons polygons;
coordf_t nozzle_dmr = EXTRUDER_CONFIG(nozzle_diameter);
coord_t delta = scale_(0.5*nozzle_dmr);
Slic3r::offset(polylines, &polygons, delta);
// for (size_t i = 0; i < polygons.size(); ++ i) svg.draw((Polyline)polygons[i], "blue");
svg.draw(last_pos, "green", 3);
svg.draw(polygon.points[idx_min], "yellow", 3);
svg.Close();
}
#endif
return polygon.points[idx_min];
} else { // spRandom
if (po->print()->default_region_config().external_perimeters_first) {
if (loop.role() == erExternalPerimeter)
last_pos = this->get_random_seam(layer_idx, polygon, po_idx);
else {
// Internal perimeters will just use last_pos.
}
} else {
if (loop.loop_role() == elrContourInternalPerimeter && loop.role() != erExternalPerimeter) {
// This loop does not contain any other loop. Set a random position.
// The other loops will get a seam close to the random point chosen
// on the innermost contour.
last_pos = this->get_random_seam(layer_idx, polygon, po_idx);
m_last_loop_was_external = false;
}
if (loop.role() == erExternalPerimeter) {
if (m_last_loop_was_external) {
// There was no internal perimeter before this one.
last_pos = this->get_random_seam(layer_idx, polygon, po_idx);
} else {
if (is_custom_seam_on_layer(layer_idx, po_idx)) {
// There is a possibility that the loop will be influenced by custom
// seam enforcer/blocker. In this case do not inherit the seam
// from internal loops (which may conflict with the custom selection
// and generate another random one.
bool saw_custom = false;
Point candidate = this->get_random_seam(layer_idx, polygon, po_idx, &saw_custom);
if (saw_custom)
last_pos = candidate;
}
}
m_last_loop_was_external = true;
}
}
return last_pos;
}
}
Point SeamPlacer::get_random_seam(size_t layer_idx, const Polygon& polygon, size_t po_idx,
bool* saw_custom) const
{
// Parametrize the polygon by its length.
std::vector<float> lengths = polygon.parameter_by_length();
// Which of the points are inside enforcers/blockers?
std::vector<size_t> enforcers_idxs;
std::vector<size_t> blockers_idxs;
this->get_enforcers_and_blockers(layer_idx, polygon, po_idx, enforcers_idxs, blockers_idxs);
bool has_enforcers = ! enforcers_idxs.empty();
bool has_blockers = ! blockers_idxs.empty();
if (saw_custom)
*saw_custom = has_enforcers || has_blockers;
// FIXME FIXME FIXME: This is just to test the outcome and whether it is
// reasonable. The algorithm should really sum the length of all available
// pieces, get a random length and find the respective point.
float rand_len = 0.f;
size_t pt_idx = 0;
do {
rand_len = lengths.back() * (rand()/float(RAND_MAX));
auto it = std::lower_bound(lengths.begin(), lengths.end(), rand_len);
pt_idx = it == lengths.end() ? 0 : (it-lengths.begin()-1);
// If there are blockers and the point is inside, repeat.
// If there are enforcers and the point is NOT inside, repeat.
} while ((has_blockers && std::binary_search(blockers_idxs.begin(), blockers_idxs.end(), pt_idx))
|| (has_enforcers && ! std::binary_search(enforcers_idxs.begin(), enforcers_idxs.end(), pt_idx)));
if (! has_enforcers && ! has_blockers) {
// The polygon may be too coarse, calculate the point exactly.
bool last_seg = pt_idx == polygon.points.size()-1;
size_t next_idx = last_seg ? 0 : pt_idx+1;
const Point& prev = polygon.points[pt_idx];
const Point& next = polygon.points[next_idx];
assert(next_idx == 0 || pt_idx+1 == next_idx);
coordf_t diff_x = next.x() - prev.x();
coordf_t diff_y = next.y() - prev.y();
coordf_t dist = lengths[last_seg ? pt_idx+1 : next_idx] - lengths[pt_idx];
return Point(prev.x() + (rand_len - lengths[pt_idx]) * (diff_x/dist),
prev.y() + (rand_len - lengths[pt_idx]) * (diff_y/dist));
} else {
// The polygon should be dense enough.
return polygon.points[pt_idx];
}
}
void SeamPlacer::get_enforcers_and_blockers(size_t layer_id,
const Polygon& polygon,
size_t po_idx,
std::vector<size_t>& enforcers_idxs,
std::vector<size_t>& blockers_idxs) const
{
enforcers_idxs.clear();
blockers_idxs.clear();
auto is_inside = [](const Point& pt,
const CustomTrianglesPerLayer& custom_data) -> bool {
assert(! custom_data.polys.empty());
// Now ask the AABB tree which polygon we should check and check it.
size_t candidate = AABBTreeIndirect::get_candidate_idx(custom_data.tree, pt);
if (candidate != size_t(-1)
&& custom_data.polys[candidate].contains(pt))
return true;
return false;
};
if (! m_enforcers[po_idx].empty()) {
const CustomTrianglesPerLayer& enforcers = m_enforcers[po_idx][layer_id];
if (! enforcers.polys.empty()) {
for (size_t i=0; i<polygon.points.size(); ++i) {
if (is_inside(polygon.points[i], enforcers))
enforcers_idxs.emplace_back(i);
}
}
}
if (! m_blockers[po_idx].empty()) {
const CustomTrianglesPerLayer& blockers = m_blockers[po_idx][layer_id];
if (! blockers.polys.empty()) {
for (size_t i=0; i<polygon.points.size(); ++i) {
if (is_inside(polygon.points[i], blockers))
blockers_idxs.emplace_back(i);
}
}
}
}
// Go through the polygon, identify points inside support enforcers and return
// indices of points in the middle of each enforcer (measured along the contour).
static std::vector<size_t> find_enforcer_centers(const Polygon& polygon,
const std::vector<float>& lengths,
const std::vector<size_t>& enforcers_idxs)
{
std::vector<size_t> out;
assert(polygon.points.size()+1 == lengths.size());
assert(std::is_sorted(enforcers_idxs.begin(), enforcers_idxs.end()));
if (polygon.size() < 2 || enforcers_idxs.empty())
return out;
auto get_center_idx = [&polygon, &lengths](size_t start_idx, size_t end_idx) -> size_t {
assert(end_idx >= start_idx);
if (start_idx == end_idx)
return start_idx;
float t_c = lengths[start_idx] + 0.5f * (lengths[end_idx] - lengths[start_idx]);
auto it = std::lower_bound(lengths.begin() + start_idx, lengths.begin() + end_idx, t_c);
int ret = it - lengths.begin();
return ret;
};
int last_enforcer_start_idx = enforcers_idxs.front();
bool first_pt_in_list = enforcers_idxs.front() != 0;
bool last_pt_in_list = enforcers_idxs.back() == polygon.points.size() - 1;
bool wrap_around = last_pt_in_list && first_pt_in_list;
for (size_t i=0; i<enforcers_idxs.size(); ++i) {
if (i != enforcers_idxs.size() - 1) {
if (enforcers_idxs[i+1] != enforcers_idxs[i] + 1) {
// i is last point of current enforcer
out.push_back(get_center_idx(last_enforcer_start_idx, enforcers_idxs[i]));
last_enforcer_start_idx = enforcers_idxs[i+1];
}
} else {
if (! wrap_around) {
// we can safely use the last enforcer point.
out.push_back(get_center_idx(last_enforcer_start_idx, enforcers_idxs[i]));
}
}
}
if (wrap_around) {
// Update first center already found.
if (out.empty()) {
// Probably an enforcer around the whole contour. Return nothing.
return out;
}
// find last point of the enforcer at the beginning:
size_t idx = 0;
while (enforcers_idxs[idx]+1 == enforcers_idxs[idx+1])
++idx;
float t_s = lengths[last_enforcer_start_idx];
float t_e = lengths[idx];
float half_dist = 0.5f * (t_e + lengths.back() - t_s);
float t_c = (half_dist > t_e) ? t_s + half_dist : t_e - half_dist;
auto it = std::lower_bound(lengths.begin(), lengths.end(), t_c);
out[0] = it - lengths.begin();
if (out[0] == lengths.size() - 1)
--out[0];
assert(out[0] < lengths.size() - 1);
}
return out;
}
void SeamPlacer::apply_custom_seam(const Polygon& polygon, size_t po_idx,
std::vector<float>& penalties,
const std::vector<float>& lengths,
int layer_id, SeamPosition seam_position) const
{
if (! is_custom_seam_on_layer(layer_id, po_idx))
return;
std::vector<size_t> enforcers_idxs;
std::vector<size_t> blockers_idxs;
this->get_enforcers_and_blockers(layer_id, polygon, po_idx, enforcers_idxs, blockers_idxs);
for (size_t i : enforcers_idxs) {
assert(i < penalties.size());
penalties[i] -= float(ENFORCER_BLOCKER_PENALTY);
}
for (size_t i : blockers_idxs) {
assert(i < penalties.size());
penalties[i] += float(ENFORCER_BLOCKER_PENALTY);
}
if (seam_position == spAligned) {
std::vector<size_t> enf_centers = find_enforcer_centers(polygon, lengths, enforcers_idxs);
for (size_t idx : enf_centers) {
assert(idx < penalties.size());
penalties[idx] += ENFORCER_CENTER_PENALTY;
}
}
////////////////////////
// std::ostringstream os;
// os << std::setw(3) << std::setfill('0') << layer_id;
// int a = scale_(20.);
// SVG svg("custom_seam" + os.str() + ".svg", BoundingBox(Point(-a, -a), Point(a, a)));
// /*if (! m_enforcers.empty())
// svg.draw(m_enforcers[layer_id], "blue");
// if (! m_blockers.empty())
// svg.draw(m_blockers[layer_id], "red");*/
// size_t min_idx = std::min_element(penalties.begin(), penalties.end()) - penalties.begin();
// //svg.draw(polygon.points[idx_min], "red", 6e5);
// for (size_t i=0; i<polygon.points.size(); ++i) {
// std::string fill;
// coord_t size = 0;
// if (min_idx == i) {
// fill = "yellow";
// size = 5e5;
// } else {
// fill = (std::find(enforcers_idxs.begin(), enforcers_idxs.end(), i) != enforcers_idxs.end() ? "green" : "black");
// if (std::find(enf_centers.begin(), enf_centers.end(), i) != enf_centers.end()) {
// size = 5e5;
// fill = "blue";
// }
// }
// if (i != 0)
// svg.draw(polygon.points[i], fill, size);
// else
// svg.draw(polygon.points[i], "red", 5e5);
// }
//////////////////////
}
std::optional<Point> SeamHistory::get_last_seam(const PrintObject* po, size_t layer_id, const BoundingBox& island_bb)
{
assert(layer_id >= m_layer_id);
if (layer_id > m_layer_id) {
// Get seam was called for different layer than last time.
m_data_last_layer = m_data_this_layer;
m_data_this_layer.clear();
m_layer_id = layer_id;
}
std::optional<Point> out;
auto seams_it = m_data_last_layer.find(po);
if (seams_it == m_data_last_layer.end())
return out;
const std::vector<SeamPoint>& seam_data_po = seams_it->second;
// Find a bounding-box on the last layer that is close to one we see now.
double min_score = std::numeric_limits<double>::max();
for (const SeamPoint& sp : seam_data_po) {
const BoundingBox& bb = sp.m_island_bb;
if (! bb.overlap(island_bb)) {
// This bb does not even overlap. It is likely unrelated.
continue;
}
double score = std::pow(bb.min(0) - island_bb.min(0), 2.)
+ std::pow(bb.min(1) - island_bb.min(1), 2.)
+ std::pow(bb.max(0) - island_bb.max(0), 2.)
+ std::pow(bb.max(1) - island_bb.max(1), 2.);
if (score < min_score) {
min_score = score;
out = sp.m_pos;
}
}
return out;
}
void SeamHistory::add_seam(const PrintObject* po, const Point& pos, const BoundingBox& island_bb)
{
m_data_this_layer[po].push_back({pos, island_bb});;
}
void SeamHistory::clear()
{
m_layer_id = 0;
m_data_last_layer.clear();
m_data_this_layer.clear();
}
}