PrusaSlicer-NonPlainar/src/libslic3r/MultiPoint.cpp

416 lines
14 KiB
C++

#include "MultiPoint.hpp"
#include "BoundingBox.hpp"
namespace Slic3r {
void MultiPoint::scale(double factor)
{
for (Point &pt : points)
pt *= factor;
}
void MultiPoint::scale(double factor_x, double factor_y)
{
for (Point &pt : points)
{
pt(0) = coord_t(pt(0) * factor_x);
pt(1) = coord_t(pt(1) * factor_y);
}
}
void MultiPoint::translate(double x, double y)
{
Vector v(x, y);
for (Point &pt : points)
pt += v;
}
void MultiPoint::translate(const Point &v)
{
for (Point &pt : points)
pt += v;
}
void MultiPoint::rotate(double cos_angle, double sin_angle)
{
for (Point &pt : this->points) {
double cur_x = double(pt(0));
double cur_y = double(pt(1));
pt(0) = coord_t(round(cos_angle * cur_x - sin_angle * cur_y));
pt(1) = coord_t(round(cos_angle * cur_y + sin_angle * cur_x));
}
}
void MultiPoint::rotate(double angle, const Point &center)
{
double s = sin(angle);
double c = cos(angle);
for (Point &pt : points) {
Vec2crd v(pt - center);
pt(0) = (coord_t)round(double(center(0)) + c * v[0] - s * v[1]);
pt(1) = (coord_t)round(double(center(1)) + c * v[1] + s * v[0]);
}
}
double MultiPoint::length() const
{
Lines lines = this->lines();
double len = 0;
for (Lines::iterator it = lines.begin(); it != lines.end(); ++it) {
len += it->length();
}
return len;
}
int MultiPoint::find_point(const Point &point) const
{
for (const Point &pt : this->points)
if (pt == point)
return int(&pt - &this->points.front());
return -1; // not found
}
bool MultiPoint::has_boundary_point(const Point &point) const
{
double dist = (point.projection_onto(*this) - point).cast<double>().norm();
return dist < SCALED_EPSILON;
}
BoundingBox MultiPoint::bounding_box() const
{
return BoundingBox(this->points);
}
bool MultiPoint::has_duplicate_points() const
{
for (size_t i = 1; i < points.size(); ++i)
if (points[i-1] == points[i])
return true;
return false;
}
bool MultiPoint::remove_duplicate_points()
{
size_t j = 0;
for (size_t i = 1; i < points.size(); ++i) {
if (points[j] == points[i]) {
// Just increase index i.
} else {
++ j;
if (j < i)
points[j] = points[i];
}
}
if (++ j < points.size()) {
points.erase(points.begin() + j, points.end());
return true;
}
return false;
}
bool MultiPoint::intersection(const Line& line, Point* intersection) const
{
Lines lines = this->lines();
for (Lines::const_iterator it = lines.begin(); it != lines.end(); ++it) {
if (it->intersection(line, intersection)) return true;
}
return false;
}
bool MultiPoint::first_intersection(const Line& line, Point* intersection) const
{
bool found = false;
double dmin = 0.;
for (const Line &l : this->lines()) {
Point ip;
if (l.intersection(line, &ip)) {
if (! found) {
found = true;
dmin = (line.a - ip).cast<double>().norm();
*intersection = ip;
} else {
double d = (line.a - ip).cast<double>().norm();
if (d < dmin) {
dmin = d;
*intersection = ip;
}
}
}
}
return found;
}
std::vector<Point> MultiPoint::_douglas_peucker(const std::vector<Point>& pts, const double tolerance)
{
std::vector<Point> result_pts;
double tolerance_sq = tolerance * tolerance;
if (! pts.empty()) {
const Point *anchor = &pts.front();
size_t anchor_idx = 0;
const Point *floater = &pts.back();
size_t floater_idx = pts.size() - 1;
result_pts.reserve(pts.size());
result_pts.emplace_back(*anchor);
if (anchor_idx != floater_idx) {
assert(pts.size() > 1);
std::vector<size_t> dpStack;
dpStack.reserve(pts.size());
dpStack.emplace_back(floater_idx);
for (;;) {
double max_dist_sq = 0.0;
size_t furthest_idx = anchor_idx;
// find point furthest from line seg created by (anchor, floater) and note it
for (size_t i = anchor_idx + 1; i < floater_idx; ++ i) {
double dist_sq = Line::distance_to_squared(pts[i], *anchor, *floater);
if (dist_sq > max_dist_sq) {
max_dist_sq = dist_sq;
furthest_idx = i;
}
}
// remove point if less than tolerance
if (max_dist_sq <= tolerance_sq) {
result_pts.emplace_back(*floater);
anchor_idx = floater_idx;
anchor = floater;
assert(dpStack.back() == floater_idx);
dpStack.pop_back();
if (dpStack.empty())
break;
floater_idx = dpStack.back();
} else {
floater_idx = furthest_idx;
dpStack.emplace_back(floater_idx);
}
floater = &pts[floater_idx];
}
}
assert(result_pts.front() == pts.front());
assert(result_pts.back() == pts.back());
#if 0
{
static int iRun = 0;
BoundingBox bbox(pts);
BoundingBox bbox2(result_pts);
bbox.merge(bbox2);
SVG svg(debug_out_path("douglas_peucker_%d.svg", iRun ++).c_str(), bbox);
if (pts.front() == pts.back())
svg.draw(Polygon(pts), "black");
else
svg.draw(Polyline(pts), "black");
if (result_pts.front() == result_pts.back())
svg.draw(Polygon(result_pts), "green", scale_(0.1));
else
svg.draw(Polyline(result_pts), "green", scale_(0.1));
}
#endif
}
return result_pts;
}
// Visivalingam simplification algorithm https://github.com/slic3r/Slic3r/pull/3825
// thanks to @fuchstraumer
/*
struct - vis_node
Used with the visivalignam simplification algorithm, which needs to be able to find a points
successors and predecessors to operate succesfully. Since this struct is only used in one
location, it could probably be dropped into a namespace to avoid polluting the slic3r namespace.
Source: https://github.com/shortsleeves/visvalingam_simplify
^ Provided original algorithm implementation. I've only changed things a bit to "clean" them up
(i.e be more like my personal style), and managed to do this without requiring a binheap implementation
*/
struct vis_node{
vis_node(const size_t& idx, const size_t& _prev_idx, const size_t& _next_idx, const double& _area) : pt_idx(idx), prev_idx(_prev_idx), next_idx(_next_idx), area(_area) {}
// Indices into a Points container, from which this object was constructed
size_t pt_idx, prev_idx, next_idx;
// Effective area of this "node"
double area;
// Overloaded operator used to sort the binheap
// Greater area = "more important" node. So, this node is less than the
// other node if it's area is less than the other node's area
bool operator<(const vis_node& other) { return (this->area < other.area); }
};
Points MultiPoint::visivalingam(const Points& pts, const double& tolerance)
{
// Make sure there's enough points in "pts" to bother with simplification.
assert(pts.size() >= 2);
// Result object
Points results;
// Lambda to calculate effective area spanned by a point and its immediate
// successor + predecessor.
auto effective_area = [pts](const size_t& curr_pt_idx, const size_t& prev_pt_idx, const size_t& next_pt_idx)->coordf_t {
const Point& curr = pts[curr_pt_idx];
const Point& prev = pts[prev_pt_idx];
const Point& next = pts[next_pt_idx];
// Use point objects as vector-distances
const Vec2d curr_to_next = (next - curr).cast<double>();
const Vec2d prev_to_next = (prev - curr).cast<double>();
// Take cross product of these two vector distances
return 0.50 * abs(cross2(curr_to_next, prev_to_next));
};
// We store the effective areas for each node
std::vector<coordf_t> areas;
areas.reserve(pts.size());
// Construct the initial set of nodes. We will make a heap out of the "heap" vector using
// std::make_heap. node_list is used later.
std::vector<vis_node*> node_list;
node_list.resize(pts.size());
std::vector<vis_node*> heap;
heap.reserve(pts.size());
for (size_t i = 1; i < pts.size() - 1; ++ i) {
// Get effective area of current node.
coordf_t area = effective_area(i, i - 1, i + 1);
// If area is greater than some arbitrarily small value, use it.
node_list[i] = new vis_node(i, i - 1, i + 1, area);
heap.push_back(node_list[i]);
}
// Call std::make_heap, which uses the < operator by default to make "heap" into
// a binheap, sorted by the < operator we defind in the vis_node struct
std::make_heap(heap.begin(), heap.end());
// Start comparing areas. Set min_area to an outrageous value initially.
double min_area = -std::numeric_limits<double>::max();
while (!heap.empty()) {
// Get current node.
vis_node* curr = heap.front();
// Pop node we just retrieved off the heap. pop_heap moves front element in vector
// to the back, so we can call pop_back()
std::pop_heap(heap.begin(), heap.end());
heap.pop_back();
// Sanity assert check
assert(curr == node_list[curr->pt_idx]);
// If the current pt'ss area is less than that of the previous pt's area
// use the last pt's area instead. This ensures we don't elimate the current
// point without eliminating the previous
min_area = std::max(min_area, curr->area);
// Update prev
vis_node* prev = node_list[curr->prev_idx];
if(prev != nullptr){
prev->next_idx = curr->next_idx;
prev->area = effective_area(prev->pt_idx, prev->prev_idx, prev->next_idx);
// For some reason, std::make_heap() is the fastest way to resort the heap. Probably needs testing.
std::make_heap(heap.begin(), heap.end());
}
// Update next
vis_node* next = node_list[curr->next_idx];
if(next != nullptr){
next->prev_idx = curr->prev_idx;
next->area = effective_area(next->pt_idx, next->prev_idx, next->next_idx);
std::make_heap(heap.begin(), heap.end());
}
areas[curr->pt_idx] = min_area;
node_list[curr->pt_idx] = nullptr;
delete curr;
}
// Clear node list and shrink_to_fit() (to free actual memory). Not necessary. Could be removed.
node_list.clear();
node_list.shrink_to_fit();
// This lambda is how we test whether or not to keep a point.
auto use_point = [areas, tolerance](const size_t& idx)->bool {
assert(idx < areas.size());
// Return true at front/back of path/areas
if(idx == 0 || idx == areas.size() - 1){
return true;
}
// Return true if area at idx is greater than minimum area to consider "valid"
else{
return areas[idx] > tolerance;
}
};
// Use previously defined lambda to build results.
for (size_t i = 0; i < pts.size(); ++i) {
if (use_point(i)){
results.push_back(pts[i]);
}
}
// Check that results has at least two points
assert(results.size() >= 2);
// Return simplified vector of points
return results;
}
void MultiPoint3::translate(double x, double y)
{
for (Vec3crd &p : points) {
p(0) += coord_t(x);
p(1) += coord_t(y);
}
}
void MultiPoint3::translate(const Point& vector)
{
this->translate(vector(0), vector(1));
}
double MultiPoint3::length() const
{
double len = 0.0;
for (const Line3& line : this->lines())
len += line.length();
return len;
}
BoundingBox3 MultiPoint3::bounding_box() const
{
return BoundingBox3(points);
}
bool MultiPoint3::remove_duplicate_points()
{
size_t j = 0;
for (size_t i = 1; i < points.size(); ++i) {
if (points[j] == points[i]) {
// Just increase index i.
} else {
++ j;
if (j < i)
points[j] = points[i];
}
}
if (++j < points.size())
{
points.erase(points.begin() + j, points.end());
return true;
}
return false;
}
BoundingBox get_extents(const MultiPoint &mp)
{
return BoundingBox(mp.points);
}
BoundingBox get_extents_rotated(const Points &points, double angle)
{
BoundingBox bbox;
if (! points.empty()) {
double s = sin(angle);
double c = cos(angle);
Points::const_iterator it = points.begin();
double cur_x = (double)(*it)(0);
double cur_y = (double)(*it)(1);
bbox.min(0) = bbox.max(0) = (coord_t)round(c * cur_x - s * cur_y);
bbox.min(1) = bbox.max(1) = (coord_t)round(c * cur_y + s * cur_x);
for (++it; it != points.end(); ++it) {
double cur_x = (double)(*it)(0);
double cur_y = (double)(*it)(1);
coord_t x = (coord_t)round(c * cur_x - s * cur_y);
coord_t y = (coord_t)round(c * cur_y + s * cur_x);
bbox.min(0) = std::min(x, bbox.min(0));
bbox.min(1) = std::min(y, bbox.min(1));
bbox.max(0) = std::max(x, bbox.max(0));
bbox.max(1) = std::max(y, bbox.max(1));
}
bbox.defined = true;
}
return bbox;
}
BoundingBox get_extents_rotated(const MultiPoint &mp, double angle)
{
return get_extents_rotated(mp.points, angle);
}
}