1/**************************************************************************/
2/* convex_polygon_shape_2d.cpp */
3/**************************************************************************/
4/* This file is part of: */
5/* GODOT ENGINE */
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8/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
9/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
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29/**************************************************************************/
30
31#include "convex_polygon_shape_2d.h"
32
33#include "core/math/geometry_2d.h"
34#include "servers/physics_server_2d.h"
35#include "servers/rendering_server.h"
36
37bool ConvexPolygonShape2D::_edit_is_selected_on_click(const Point2 &p_point, double p_tolerance) const {
38 return Geometry2D::is_point_in_polygon(p_point, points);
39}
40
41#ifdef DEBUG_ENABLED
42// Check if point p3 is to the left of [p1, p2] segment or on it.
43bool left_test(const Vector2 &p1, const Vector2 &p2, const Vector2 &p3) {
44 Vector2 p12 = p2 - p1;
45 Vector2 p13 = p3 - p1;
46 // If the value of the cross product is positive or zero; p3 is to the left or on the segment, respectively.
47 return p12.cross(p13) >= 0;
48}
49
50bool is_convex(const Vector<Vector2> &p_points) {
51 // Pre-condition: Polygon is in counter-clockwise order.
52 int polygon_size = p_points.size();
53 for (int i = 0; i < polygon_size && polygon_size > 3; i++) {
54 int j = (i + 1) % polygon_size;
55 int k = (j + 1) % polygon_size;
56 // If any consecutive three points fail left-test, then there is a concavity.
57 if (!left_test(p_points[i], p_points[j], p_points[k])) {
58 return false;
59 }
60 }
61
62 return true;
63}
64#endif
65
66void ConvexPolygonShape2D::_update_shape() {
67 Vector<Vector2> final_points = points;
68 if (Geometry2D::is_polygon_clockwise(final_points)) { //needs to be counter clockwise
69 final_points.reverse();
70 }
71#ifdef DEBUG_ENABLED
72 if (!is_convex(final_points)) {
73 WARN_PRINT("Concave polygon is assigned to ConvexPolygonShape2D.");
74 }
75#endif
76 PhysicsServer2D::get_singleton()->shape_set_data(get_rid(), final_points);
77 emit_changed();
78}
79
80void ConvexPolygonShape2D::set_point_cloud(const Vector<Vector2> &p_points) {
81 Vector<Point2> hull = Geometry2D::convex_hull(p_points);
82 ERR_FAIL_COND(hull.size() < 3);
83 set_points(hull);
84}
85
86void ConvexPolygonShape2D::set_points(const Vector<Vector2> &p_points) {
87 points = p_points;
88
89 _update_shape();
90}
91
92Vector<Vector2> ConvexPolygonShape2D::get_points() const {
93 return points;
94}
95
96void ConvexPolygonShape2D::_bind_methods() {
97 ClassDB::bind_method(D_METHOD("set_point_cloud", "point_cloud"), &ConvexPolygonShape2D::set_point_cloud);
98 ClassDB::bind_method(D_METHOD("set_points", "points"), &ConvexPolygonShape2D::set_points);
99 ClassDB::bind_method(D_METHOD("get_points"), &ConvexPolygonShape2D::get_points);
100
101 ADD_PROPERTY(PropertyInfo(Variant::PACKED_VECTOR2_ARRAY, "points"), "set_points", "get_points");
102}
103
104void ConvexPolygonShape2D::draw(const RID &p_to_rid, const Color &p_color) {
105 if (points.size() < 3) {
106 return;
107 }
108
109 Vector<Color> col = { p_color };
110 RenderingServer::get_singleton()->canvas_item_add_polygon(p_to_rid, points, col);
111
112 if (is_collision_outline_enabled()) {
113 col = { Color(p_color, 1.0) };
114 RenderingServer::get_singleton()->canvas_item_add_polyline(p_to_rid, points, col);
115 // Draw the last segment.
116 RenderingServer::get_singleton()->canvas_item_add_line(p_to_rid, points[points.size() - 1], points[0], Color(p_color, 1.0));
117 }
118}
119
120Rect2 ConvexPolygonShape2D::get_rect() const {
121 Rect2 rect;
122 for (int i = 0; i < points.size(); i++) {
123 if (i == 0) {
124 rect.position = points[i];
125 } else {
126 rect.expand_to(points[i]);
127 }
128 }
129
130 return rect;
131}
132
133real_t ConvexPolygonShape2D::get_enclosing_radius() const {
134 real_t r = 0.0;
135 for (int i(0); i < get_points().size(); i++) {
136 r = MAX(get_points()[i].length_squared(), r);
137 }
138 return Math::sqrt(r);
139}
140
141ConvexPolygonShape2D::ConvexPolygonShape2D() :
142 Shape2D(PhysicsServer2D::get_singleton()->convex_polygon_shape_create()) {
143}
144