PrusaSlicer-NonPlainar/src/libslic3r/EdgeGrid.hpp
2021-02-11 13:40:15 +01:00

402 lines
14 KiB
C++

#ifndef slic3r_EdgeGrid_hpp_
#define slic3r_EdgeGrid_hpp_
#include <stdint.h>
#include <math.h>
#include "Point.hpp"
#include "BoundingBox.hpp"
#include "ExPolygon.hpp"
#include "ExPolygonCollection.hpp"
namespace Slic3r {
namespace EdgeGrid {
class Contour {
public:
Contour() = default;
Contour(const Slic3r::Point *begin, const Slic3r::Point *end, bool open) : m_begin(begin), m_end(end), m_open(open) {}
Contour(const Slic3r::Point *data, size_t size, bool open) : Contour(data, data + size, open) {}
Contour(const std::vector<Slic3r::Point> &pts, bool open) : Contour(pts.data(), pts.size(), open) {}
const Slic3r::Point *begin() const { return m_begin; }
const Slic3r::Point *end() const { return m_end; }
bool open() const { return m_open; }
bool closed() const { return ! m_open; }
// Start point of a segment idx.
const Slic3r::Point& segment_start(size_t idx) const {
assert(idx < this->num_segments());
return m_begin[idx];
}
// End point of a segment idx.
const Slic3r::Point& segment_end(size_t idx) const {
assert(idx < this->num_segments());
const Slic3r::Point *ptr = m_begin + idx + 1;
return ptr == m_end ? *m_begin : *ptr;
}
// Start point of a segment preceding idx.
const Slic3r::Point& segment_prev(size_t idx) const {
assert(idx < this->num_segments());
assert(idx > 0 || ! m_open);
return idx == 0 ? m_end[-1] : m_begin[idx - 1];
}
// Index of a segment preceding idx.
const size_t segment_idx_prev(size_t idx) const {
assert(idx < this->num_segments());
assert(idx > 0 || ! m_open);
return (idx == 0 ? this->size() : idx) - 1;
}
// Index of a segment preceding idx.
const size_t segment_idx_next(size_t idx) const {
assert(idx < this->num_segments());
++ idx;
return m_begin + idx == m_end ? 0 : idx;
}
size_t num_segments() const { return this->size() - (m_open ? 1 : 0); }
private:
size_t size() const { return m_end - m_begin; }
const Slic3r::Point *m_begin { nullptr };
const Slic3r::Point *m_end { nullptr };
bool m_open { false };
};
class Grid
{
public:
Grid() = default;
Grid(const BoundingBox &bbox) : m_bbox(bbox) {}
void set_bbox(const BoundingBox &bbox) { m_bbox = bbox; }
// Fill in the grid with open polylines or closed contours.
// If open flag is indicated, then polylines_or_polygons are considered to be open by default.
// Only if the first point of a polyline is equal to the last point of a polyline,
// then the polyline is considered to be closed and the last repeated point is removed when
// inserted into the EdgeGrid.
// Most of the Grid functions expect all the contours to be closed, you have been warned!
void create(const std::vector<Points> &polylines_or_polygons, coord_t resolution, bool open);
void create(const Polygons &polygons, const Polylines &polylines, coord_t resolution);
// Fill in the grid with closed contours.
void create(const Polygons &polygons, coord_t resolution);
void create(const std::vector<const Polygon*> &polygons, coord_t resolution);
void create(const std::vector<Points> &polygons, coord_t resolution) { this->create(polygons, resolution, false); }
void create(const ExPolygon &expoly, coord_t resolution);
void create(const ExPolygons &expolygons, coord_t resolution);
void create(const ExPolygonCollection &expolygons, coord_t resolution);
const std::vector<Contour>& contours() const { return m_contours; }
#if 0
// Test, whether the edges inside the grid intersect with the polygons provided.
bool intersect(const MultiPoint &polyline, bool closed);
bool intersect(const Polygon &polygon) { return intersect(static_cast<const MultiPoint&>(polygon), true); }
bool intersect(const Polygons &polygons) { for (size_t i = 0; i < polygons.size(); ++ i) if (intersect(polygons[i])) return true; return false; }
bool intersect(const ExPolygon &expoly) { if (intersect(expoly.contour)) return true; for (size_t i = 0; i < expoly.holes.size(); ++ i) if (intersect(expoly.holes[i])) return true; return false; }
bool intersect(const ExPolygons &expolygons) { for (size_t i = 0; i < expolygons.size(); ++ i) if (intersect(expolygons[i])) return true; return false; }
bool intersect(const ExPolygonCollection &expolygons) { return intersect(expolygons.expolygons); }
// Test, whether a point is inside a contour.
bool inside(const Point &pt);
#endif
// Fill in a rough m_signed_distance_field from the edge grid.
// The rough SDF is used by signed_distance() for distances outside of the search_radius.
// Only call this function for closed contours!
void calculate_sdf();
// Return an estimate of the signed distance based on m_signed_distance_field grid.
float signed_distance_bilinear(const Point &pt) const;
// Calculate a signed distance to the contours in search_radius from the point.
// Only call this function for closed contours!
struct ClosestPointResult {
size_t contour_idx = size_t(-1);
size_t start_point_idx = size_t(-1);
// Signed distance to the closest point.
double distance = std::numeric_limits<double>::max();
// Parameter of the closest point on edge starting with start_point_idx <0, 1)
double t = 0.;
bool valid() const { return contour_idx != size_t(-1); }
};
ClosestPointResult closest_point_signed_distance(const Point &pt, coord_t search_radius) const;
// Only call this function for closed contours!
bool signed_distance_edges(const Point &pt, coord_t search_radius, coordf_t &result_min_dist, bool *pon_segment = nullptr) const;
// Calculate a signed distance to the contours in search_radius from the point. If no edge is found in search_radius,
// return an interpolated value from m_signed_distance_field, if it exists.
// Only call this function for closed contours!
bool signed_distance(const Point &pt, coord_t search_radius, coordf_t &result_min_dist) const;
const BoundingBox& bbox() const { return m_bbox; }
const coord_t resolution() const { return m_resolution; }
const size_t rows() const { return m_rows; }
const size_t cols() const { return m_cols; }
// For supports: Contours enclosing the rasterized edges.
Polygons contours_simplified(coord_t offset, bool fill_holes) const;
typedef std::pair<const Contour*, size_t> ContourPoint;
typedef std::pair<const Contour*, size_t> ContourEdge;
std::vector<std::pair<ContourEdge, ContourEdge>> intersecting_edges() const;
bool has_intersecting_edges() const;
template<typename VISITOR> void visit_cells_intersecting_line(Slic3r::Point p1, Slic3r::Point p2, VISITOR &visitor) const
{
// End points of the line segment.
assert(m_bbox.contains(p1));
assert(m_bbox.contains(p2));
p1 -= m_bbox.min;
p2 -= m_bbox.min;
assert(p1.x() >= 0 && size_t(p1.x()) < m_cols * m_resolution);
assert(p1.y() >= 0 && size_t(p1.y()) < m_rows * m_resolution);
assert(p2.x() >= 0 && size_t(p2.x()) < m_cols * m_resolution);
assert(p2.y() >= 0 && size_t(p2.y()) < m_rows * m_resolution);
// Get the cells of the end points.
coord_t ix = p1(0) / m_resolution;
coord_t iy = p1(1) / m_resolution;
coord_t ixb = p2(0) / m_resolution;
coord_t iyb = p2(1) / m_resolution;
assert(ix >= 0 && size_t(ix) < m_cols);
assert(iy >= 0 && size_t(iy) < m_rows);
assert(ixb >= 0 && size_t(ixb) < m_cols);
assert(iyb >= 0 && size_t(iyb) < m_rows);
// Account for the end points.
if (! visitor(iy, ix) || (ix == ixb && iy == iyb))
// Both ends fall into the same cell.
return;
// Raster the centeral part of the line.
coord_t dx = std::abs(p2(0) - p1(0));
coord_t dy = std::abs(p2(1) - p1(1));
if (p1(0) < p2(0)) {
int64_t ex = int64_t((ix + 1)*m_resolution - p1(0)) * int64_t(dy);
if (p1(1) < p2(1)) {
// x positive, y positive
int64_t ey = int64_t((iy + 1)*m_resolution - p1(1)) * int64_t(dx);
do {
assert(ix <= ixb && iy <= iyb);
if (ex < ey) {
ey -= ex;
ex = int64_t(dy) * m_resolution;
ix += 1;
assert(ix <= ixb);
}
else if (ex == ey) {
ex = int64_t(dy) * m_resolution;
ey = int64_t(dx) * m_resolution;
ix += 1;
iy += 1;
assert(ix <= ixb);
assert(iy <= iyb);
}
else {
assert(ex > ey);
ex -= ey;
ey = int64_t(dx) * m_resolution;
iy += 1;
assert(iy <= iyb);
}
if (! visitor(iy, ix))
return;
} while (ix != ixb || iy != iyb);
}
else {
// x positive, y non positive
int64_t ey = int64_t(p1(1) - iy*m_resolution) * int64_t(dx);
do {
assert(ix <= ixb && iy >= iyb);
if (ex <= ey) {
ey -= ex;
ex = int64_t(dy) * m_resolution;
ix += 1;
assert(ix <= ixb);
}
else {
ex -= ey;
ey = int64_t(dx) * m_resolution;
iy -= 1;
assert(iy >= iyb);
}
if (! visitor(iy, ix))
return;
} while (ix != ixb || iy != iyb);
}
}
else {
int64_t ex = int64_t(p1(0) - ix*m_resolution) * int64_t(dy);
if (p1(1) < p2(1)) {
// x non positive, y positive
int64_t ey = int64_t((iy + 1)*m_resolution - p1(1)) * int64_t(dx);
do {
assert(ix >= ixb && iy <= iyb);
if (ex < ey) {
ey -= ex;
ex = int64_t(dy) * m_resolution;
ix -= 1;
assert(ix >= ixb);
}
else {
assert(ex >= ey);
ex -= ey;
ey = int64_t(dx) * m_resolution;
iy += 1;
assert(iy <= iyb);
}
if (! visitor(iy, ix))
return;
} while (ix != ixb || iy != iyb);
}
else {
// x non positive, y non positive
int64_t ey = int64_t(p1(1) - iy*m_resolution) * int64_t(dx);
do {
assert(ix >= ixb && iy >= iyb);
if (ex < ey) {
ey -= ex;
ex = int64_t(dy) * m_resolution;
ix -= 1;
assert(ix >= ixb);
}
else if (ex == ey) {
// The lower edge of a grid cell belongs to the cell.
// Handle the case where the ray may cross the lower left corner of a cell in a general case,
// or a left or lower edge in a degenerate case (horizontal or vertical line).
if (dx > 0) {
ex = int64_t(dy) * m_resolution;
ix -= 1;
assert(ix >= ixb);
}
if (dy > 0) {
ey = int64_t(dx) * m_resolution;
iy -= 1;
assert(iy >= iyb);
}
}
else {
assert(ex > ey);
ex -= ey;
ey = int64_t(dx) * m_resolution;
iy -= 1;
assert(iy >= iyb);
}
if (! visitor(iy, ix))
return;
} while (ix != ixb || iy != iyb);
}
}
}
template<typename VISITOR> void visit_cells_intersecting_box(BoundingBox bbox, VISITOR &visitor) const
{
// End points of the line segment.
bbox.min -= m_bbox.min;
bbox.max -= m_bbox.min + Point(1, 1);
// Get the cells of the end points.
bbox.min /= m_resolution;
bbox.max /= m_resolution;
// Trim with the cells.
bbox.min.x() = std::max<coord_t>(bbox.min.x(), 0);
bbox.min.y() = std::max<coord_t>(bbox.min.y(), 0);
bbox.max.x() = std::min<coord_t>(bbox.max.x(), (coord_t)m_cols - 1);
bbox.max.y() = std::min<coord_t>(bbox.max.y(), (coord_t)m_rows - 1);
for (coord_t iy = bbox.min.y(); iy <= bbox.max.y(); ++ iy)
for (coord_t ix = bbox.min.x(); ix <= bbox.max.x(); ++ ix)
if (! visitor(iy, ix))
return;
}
std::pair<std::vector<std::pair<size_t, size_t>>::const_iterator, std::vector<std::pair<size_t, size_t>>::const_iterator> cell_data_range(coord_t row, coord_t col) const
{
assert(row >= 0 && size_t(row) < m_rows);
assert(col >= 0 && size_t(col) < m_cols);
const EdgeGrid::Grid::Cell &cell = m_cells[row * m_cols + col];
return std::make_pair(m_cell_data.begin() + cell.begin, m_cell_data.begin() + cell.end);
}
std::pair<const Slic3r::Point&, const Slic3r::Point&> segment(const std::pair<size_t, size_t> &contour_and_segment_idx) const
{
const Contour &contour = m_contours[contour_and_segment_idx.first];
size_t iseg = contour_and_segment_idx.second;
return std::pair<const Slic3r::Point&, const Slic3r::Point&>(contour.segment_start(iseg), contour.segment_end(iseg));
}
Line line(const std::pair<size_t, size_t> &contour_and_segment_idx) const
{
const Contour &contour = m_contours[contour_and_segment_idx.first];
size_t iseg = contour_and_segment_idx.second;
return Line(contour.segment_start(iseg), contour.segment_end(iseg));
}
protected:
struct Cell {
Cell() : begin(0), end(0) {}
size_t begin;
size_t end;
};
void create_from_m_contours(coord_t resolution);
#if 0
bool line_cell_intersect(const Point &p1, const Point &p2, const Cell &cell);
#endif
bool cell_inside_or_crossing(int r, int c) const
{
if (r < 0 || (size_t)r >= m_rows ||
c < 0 || (size_t)c >= m_cols)
// The cell is outside the domain. Hoping that the contours were correctly oriented, so
// there is a CCW outmost contour so the out of domain cells are outside.
return false;
const Cell &cell = m_cells[r * m_cols + c];
return
(cell.begin < cell.end) ||
(! m_signed_distance_field.empty() && m_signed_distance_field[r * (m_cols + 1) + c] <= 0.f);
}
// Bounding box around the contours.
BoundingBox m_bbox;
// Grid dimensions.
coord_t m_resolution;
size_t m_rows = 0;
size_t m_cols = 0;
// Referencing the source contours.
// This format allows one to work with any Slic3r fixed point contour format
// (Polygon, ExPolygon, ExPolygonCollection etc).
std::vector<Contour> m_contours;
// Referencing a contour and a line segment of m_contours.
std::vector<std::pair<size_t, size_t> > m_cell_data;
// Full grid of cells.
std::vector<Cell> m_cells;
// Distance field derived from the edge grid, seed filled by the Danielsson chamfer metric.
// May be empty.
std::vector<float> m_signed_distance_field;
};
// Debugging utility. Save the signed distance field.
extern void save_png(const Grid &grid, const BoundingBox &bbox, coord_t resolution, const char *path, size_t scale = 1);
} // namespace EdgeGrid
// Find all pairs of intersectiong edges from the set of polygons.
extern std::vector<std::pair<EdgeGrid::Grid::ContourEdge, EdgeGrid::Grid::ContourEdge>> intersecting_edges(const Polygons &polygons);
// Find all pairs of intersectiong edges from the set of polygons, highlight them in an SVG.
extern void export_intersections_to_svg(const std::string &filename, const Polygons &polygons);
} // namespace Slic3r
#endif /* slic3r_EdgeGrid_hpp_ */