Fixed wrong implementation of concave_points() and convex_points() in C++. #2384

This commit is contained in:
Alessandro Ranellucci 2014-12-07 19:53:22 +01:00
parent 95f7bcb9fe
commit 6ce651eb4a
7 changed files with 53 additions and 18 deletions

View File

@ -2,7 +2,7 @@ use Test::More;
use strict;
use warnings;
plan tests => 33;
plan tests => 38;
BEGIN {
use FindBin;
@ -213,3 +213,29 @@ my $polygons = [
is scalar(@{$square->concave_points(PI*4/3)}), 0, 'no concave vertices detected in convex polygon';
is scalar(@{$square->convex_points(PI*2/3)}), 4, 'four convex vertices detected in square';
}
{
my $triangle = Slic3r::Polygon->new(
[16000170,26257364], [714223,461012], [31286371,461008],
);
is scalar(@{$triangle->concave_points(PI*4/3)}), 0, 'no concave vertices detected in triangle';
is scalar(@{$triangle->convex_points(PI*2/3)}), 3, 'three convex vertices detected in triangle';
}
{
my $triangle = Slic3r::Polygon->new(
[16000170,26257364], [714223,461012], [20000000,461012], [31286371,461012],
);
is scalar(@{$triangle->concave_points(PI*4/3)}), 0, 'no concave vertices detected in triangle having collinear point';
is scalar(@{$triangle->convex_points(PI*2/3)}), 3, 'three convex vertices detected in triangle having collinear point';
}
{
my $triangle = Slic3r::Polygon->new(
[16000170,26257364], [714223,461012], [31286371,461008],
);
my $simplified = $triangle->simplify(250000)->[0];
is scalar(@$simplified), 3, 'triangle is never simplified to less than 3 points';
}
__END__

View File

@ -266,7 +266,7 @@ use Slic3r::Test;
my $was_extruding = 0;
my @seam_points = ();
my $print = Slic3r::Test::init_print($model_name, config => $config);
Slic3r::GCode::Reader->new->parse(Slic3r::Test::gcode($print), sub {
Slic3r::GCode::Reader->new->parse(my $gcode = Slic3r::Test::gcode($print), sub {
my ($self, $cmd, $args, $info) = @_;
if ($info->{extruding}) {

View File

@ -17,6 +17,8 @@ class MultiPoint
Points points;
operator Points() const;
MultiPoint() {};
explicit MultiPoint(const Points &_points): points(_points) {};
void scale(double factor);
void translate(double x, double y);
void translate(const Point &vector);

View File

@ -160,6 +160,13 @@ Point::ccw(const Line &line) const
return this->ccw(line.a, line.b);
}
// returns the CCW angle between this-p1 and this-p2
double
Point::ccw_angle(const Point &p1, const Point &p2) const
{
return Line(*this, p1).orientation() - Line(*this, p2).orientation();
}
Point
Point::projection_onto(const MultiPoint &poly) const
{

View File

@ -48,6 +48,7 @@ class Point
double distance_to(const Line &line) const;
double ccw(const Point &p1, const Point &p2) const;
double ccw(const Line &line) const;
double ccw_angle(const Point &p1, const Point &p2) const;
Point projection_onto(const MultiPoint &poly) const;
Point projection_onto(const Line &line) const;
Point negative() const;

View File

@ -158,8 +158,12 @@ Polygon::contains(const Point &point) const
Polygons
Polygon::simplify(double tolerance) const
{
Polygon p = *this;
p.points = MultiPoint::_douglas_peucker(p.points, tolerance);
// repeat first point at the end in order to apply Douglas-Peucker
// on the whole polygon
Points points = this->points;
points.push_back(points.front());
Polygon p(MultiPoint::_douglas_peucker(points, tolerance));
p.points.pop_back();
Polygons pp;
pp.push_back(p);
@ -225,21 +229,17 @@ Polygon::wkt() const
void
Polygon::concave_points(double angle, Points* points) const
{
/* input angle threshold is checked on the internal side of the polygon
but ccw() returns 0 for collinear, >0 for ccw and <0 for cw */
double ccw_angle = angle - PI;
// check whether first point forms a concave angle
if (this->points.front().ccw(this->points.back(), *(this->points.begin()+1)) >= ccw_angle)
if (this->points.front().ccw_angle(this->points.back(), *(this->points.begin()+1)) >= angle)
points->push_back(this->points.front());
// check whether points 1..(n-1) form concave angles
for (Points::const_iterator p = this->points.begin()+1; p != this->points.end()-1; ++p) {
if (p->ccw(*(p-1), *(p+1)) >= ccw_angle) points->push_back(*p);
if (p->ccw_angle(*(p-1), *(p+1)) >= angle) points->push_back(*p);
}
// check whether last point forms a concave angle
if (this->points.back().ccw(*(this->points.end()-2), this->points.front()) >= ccw_angle)
if (this->points.back().ccw_angle(*(this->points.end()-2), this->points.front()) >= angle)
points->push_back(this->points.back());
}
@ -252,21 +252,17 @@ Polygon::concave_points(Points* points) const
void
Polygon::convex_points(double angle, Points* points) const
{
/* input angle threshold is checked on the internal side of the polygon
but ccw() returns 0 for collinear, >0 for ccw and <0 for cw */
double ccw_angle = angle - PI;
// check whether first point forms a convex angle
if (this->points.front().ccw(this->points.back(), *(this->points.begin()+1)) <= ccw_angle)
if (this->points.front().ccw_angle(this->points.back(), *(this->points.begin()+1)) <= angle)
points->push_back(this->points.front());
// check whether points 1..(n-1) form convex angles
for (Points::const_iterator p = this->points.begin()+1; p != this->points.end()-1; ++p) {
if (p->ccw(*(p-1), *(p+1)) <= ccw_angle) points->push_back(*p);
if (p->ccw_angle(*(p-1), *(p+1)) <= angle) points->push_back(*p);
}
// check whether last point forms a convex angle
if (this->points.back().ccw(*(this->points.end()-2), this->points.front()) <= ccw_angle)
if (this->points.back().ccw_angle(*(this->points.end()-2), this->points.front()) <= angle)
points->push_back(this->points.back());
}

View File

@ -19,6 +19,9 @@ class Polygon : public MultiPoint {
operator Polyline() const;
Point& operator[](Points::size_type idx);
const Point& operator[](Points::size_type idx) const;
Polygon() {};
explicit Polygon(const Points &points): MultiPoint(points) {};
Point last_point() const;
Lines lines() const;
void lines(Lines* lines) const;