Merge pull request #56671 from Rgtemze/warn_if_concave

Warn when a concave polygon is assigned to ConvexPolygonShape2D
This commit is contained in:
Yuri Sizov 2023-04-07 14:39:41 +02:00 committed by GitHub
commit b5f532094e
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23

View File

@ -38,11 +38,41 @@ bool ConvexPolygonShape2D::_edit_is_selected_on_click(const Point2 &p_point, dou
return Geometry2D::is_point_in_polygon(p_point, points);
}
#ifdef DEBUG_ENABLED
// Check if point p3 is to the left of [p1, p2] segment or on it.
bool left_test(const Vector2 &p1, const Vector2 &p2, const Vector2 &p3) {
Vector2 p12 = p2 - p1;
Vector2 p13 = p3 - p1;
// If the value of the cross product is positive or zero; p3 is to the left or on the segment, respectively.
return p12.cross(p13) >= 0;
}
bool is_convex(const Vector<Vector2> &p_points) {
// Pre-condition: Polygon is in counter-clockwise order.
int polygon_size = p_points.size();
for (int i = 0; i < polygon_size && polygon_size > 3; i++) {
int j = (i + 1) % polygon_size;
int k = (j + 1) % polygon_size;
// If any consecutive three points fail left-test, then there is a concavity.
if (!left_test(p_points[i], p_points[j], p_points[k])) {
return false;
}
}
return true;
}
#endif
void ConvexPolygonShape2D::_update_shape() {
Vector<Vector2> final_points = points;
if (Geometry2D::is_polygon_clockwise(final_points)) { //needs to be counter clockwise
final_points.reverse();
}
#ifdef DEBUG_ENABLED
if (!is_convex(final_points)) {
WARN_PRINT("Concave polygon is assigned to ConvexPolygonShape2D.");
}
#endif
PhysicsServer2D::get_singleton()->shape_set_data(get_rid(), final_points);
emit_changed();
}