Port member initialization from constructor to declaration (C++11)

Using `clang-tidy`'s `modernize-use-default-member-init` check and
manual review of the changes, and some extra manual changes that
`clang-tidy` failed to do.

Also went manually through all of `core` to find occurrences that
`clang-tidy` couldn't handle, especially all initializations done
in a constructor without using initializer lists.

1 files changed, 15 insertions, 28 deletions

diff --git a/modules/gdnavigation/nav_utils.h b/modules/gdnavigation/nav_utils.h
index 3401284c31..388e53a66a 100644
--- a/modules/gdnavigation/nav_utils.h
+++ b/modules/gdnavigation/nav_utils.h
@@ -32,6 +32,7 @@
 #define NAV_UTILS_H
 
 #include "core/math/vector3.h"
+
 #include <vector>
 
 /**
@@ -80,19 +81,15 @@ struct Point {
 
 struct Edge {
 	/// This edge ID
-	int this_edge;
+	int this_edge = -1;
 
 	/// Other Polygon
-	Polygon *other_polygon;
+	Polygon *other_polygon = nullptr;
 
 	/// The other `Polygon` at this edge id has this `Polygon`.
-	int other_edge;
+	int other_edge = -1;
 
-	Edge() {
-		this_edge = -1;
-		other_polygon = nullptr;
-		other_edge = -1;
-	}
+	Edge() {}
 };
 
 struct Polygon {
@@ -113,39 +110,29 @@ struct Polygon {
 
 struct Connection {
 
-	Polygon *A;
-	int A_edge;
-	Polygon *B;
-	int B_edge;
+	Polygon *A = nullptr;
+	int A_edge = -1;
+	Polygon *B = nullptr;
+	int B_edge = -1;
 
-	Connection() {
-		A = nullptr;
-		B = nullptr;
-		A_edge = -1;
-		B_edge = -1;
-	}
+	Connection() {}
 };
 
 struct NavigationPoly {
-	uint32_t self_id;
+	uint32_t self_id = 0;
 	/// This poly.
 	const Polygon *poly;
 	/// The previous navigation poly (id in the `navigation_poly` array).
-	int prev_navigation_poly_id;
+	int prev_navigation_poly_id = -1;
 	/// The edge id in this `Poly` to reach the `prev_navigation_poly_id`.
-	uint32_t back_navigation_edge;
+	uint32_t back_navigation_edge = 0;
 	/// The entry location of this poly.
 	Vector3 entry;
 	/// The distance to the destination.
-	float traveled_distance;
+	float traveled_distance = 0.0;
 
 	NavigationPoly(const Polygon *p_poly) :
-			self_id(0),
-			poly(p_poly),
-			prev_navigation_poly_id(-1),
-			back_navigation_edge(0),
-			traveled_distance(0.0) {
-	}
+			poly(p_poly) {}
 
 	bool operator==(const NavigationPoly &other) const {
 		return this->poly == other.poly;