Reduce unnecessary COW on Vector by make writing explicit

This commit makes operator[] on Vector const and adds a write proxy to it.  From
now on writes to Vectors need to happen through the .write proxy. So for
instance:

Vector<int> vec;
vec.push_back(10);
std::cout << vec[0] << std::endl;
vec.write[0] = 20;

Failing to use the .write proxy will cause a compilation error.

In addition COWable datatypes can now embed a CowData pointer to their data.
This means that String, CharString, and VMap no longer use or derive from
Vector.

_ALWAYS_INLINE_ and _FORCE_INLINE_ are now equivalent for debug and non-debug
builds. This is a lot faster for Vector in the editor and while running tests.
The reason why this difference used to exist is because force-inlined methods
used to give a bad debugging experience. After extensive testing with modern
compilers this is no longer the case.

7 files changed, 35 insertions, 35 deletions

diff --git a/modules/bullet/area_bullet.cpp b/modules/bullet/area_bullet.cpp
index bfb452d109..b004641838 100644
--- a/modules/bullet/area_bullet.cpp
+++ b/modules/bullet/area_bullet.cpp
@@ -80,7 +80,7 @@ void AreaBullet::dispatch_callbacks() {
 
 	// Reverse order because I've to remove EXIT objects
 	for (int i = overlappingObjects.size() - 1; 0 <= i; --i) {
-		OverlappingObjectData &otherObj = overlappingObjects[i];
+		OverlappingObjectData &otherObj = overlappingObjects.write[i];
 
 		switch (otherObj.state) {
 			case OVERLAP_STATE_ENTER:
@@ -199,13 +199,13 @@ void AreaBullet::add_overlap(CollisionObjectBullet *p_otherObject) {
 
 void AreaBullet::put_overlap_as_exit(int p_index) {
 	scratch();
-	overlappingObjects[p_index].state = OVERLAP_STATE_EXIT;
+	overlappingObjects.write[p_index].state = OVERLAP_STATE_EXIT;
 }
 
 void AreaBullet::put_overlap_as_inside(int p_index) {
 	// This check is required to be sure this body was inside
 	if (OVERLAP_STATE_DIRTY == overlappingObjects[p_index].state) {
-		overlappingObjects[p_index].state = OVERLAP_STATE_INSIDE;
+		overlappingObjects.write[p_index].state = OVERLAP_STATE_INSIDE;
 	}
 }
 
diff --git a/modules/bullet/collision_object_bullet.cpp b/modules/bullet/collision_object_bullet.cpp
index 1d63318fd7..271cdb0223 100644
--- a/modules/bullet/collision_object_bullet.cpp
+++ b/modules/bullet/collision_object_bullet.cpp
@@ -223,7 +223,7 @@ void RigidCollisionObjectBullet::add_shape(ShapeBullet *p_shape, const Transform
 }
 
 void RigidCollisionObjectBullet::set_shape(int p_index, ShapeBullet *p_shape) {
-	ShapeWrapper &shp = shapes[p_index];
+	ShapeWrapper &shp = shapes.write[p_index];
 	shp.shape->remove_owner(this);
 	p_shape->add_owner(this);
 	shp.shape = p_shape;
@@ -233,8 +233,8 @@ void RigidCollisionObjectBullet::set_shape(int p_index, ShapeBullet *p_shape) {
 void RigidCollisionObjectBullet::set_shape_transform(int p_index, const Transform &p_transform) {
 	ERR_FAIL_INDEX(p_index, get_shape_count());
 
-	shapes[p_index].set_transform(p_transform);
-	on_shape_changed(shapes[p_index].shape);
+	shapes.write[p_index].set_transform(p_transform);
+	on_shape_changed(shapes.write[p_index].shape);
 }
 
 void RigidCollisionObjectBullet::remove_shape(ShapeBullet *p_shape) {
@@ -287,7 +287,7 @@ void RigidCollisionObjectBullet::on_shape_changed(const ShapeBullet *const p_sha
 	const int size = shapes.size();
 	for (int i = 0; i < size; ++i) {
 		if (shapes[i].shape == p_shape) {
-			bulletdelete(shapes[i].bt_shape);
+			bulletdelete(shapes.write[i].bt_shape);
 		}
 	}
 	on_shapes_changed();
@@ -307,7 +307,7 @@ void RigidCollisionObjectBullet::on_shapes_changed() {
 	// Reset shape if required
 	if (force_shape_reset) {
 		for (i = 0; i < shapes_size; ++i) {
-			shpWrapper = &shapes[i];
+			shpWrapper = &shapes.write[i];
 			bulletdelete(shpWrapper->bt_shape);
 		}
 		force_shape_reset = false;
@@ -316,7 +316,7 @@ void RigidCollisionObjectBullet::on_shapes_changed() {
 	// Insert all shapes
 	btVector3 body_scale(get_bt_body_scale());
 	for (i = 0; i < shapes_size; ++i) {
-		shpWrapper = &shapes[i];
+		shpWrapper = &shapes.write[i];
 		if (shpWrapper->active) {
 			if (!shpWrapper->bt_shape) {
 				shpWrapper->bt_shape = shpWrapper->shape->create_bt_shape(shpWrapper->scale * body_scale);
@@ -334,7 +334,7 @@ void RigidCollisionObjectBullet::on_shapes_changed() {
 }
 
 void RigidCollisionObjectBullet::set_shape_disabled(int p_index, bool p_disabled) {
-	shapes[p_index].active = !p_disabled;
+	shapes.write[p_index].active = !p_disabled;
 	on_shapes_changed();
 }
 
@@ -348,7 +348,7 @@ void RigidCollisionObjectBullet::on_body_scale_changed() {
 }
 
 void RigidCollisionObjectBullet::internal_shape_destroy(int p_index, bool p_permanentlyFromThisBody) {
-	ShapeWrapper &shp = shapes[p_index];
+	ShapeWrapper &shp = shapes.write[p_index];
 	shp.shape->remove_owner(this, p_permanentlyFromThisBody);
 	bulletdelete(shp.bt_shape);
 }
diff --git a/modules/bullet/rigid_body_bullet.cpp b/modules/bullet/rigid_body_bullet.cpp
index 18f8f5f677..52453eae17 100644
--- a/modules/bullet/rigid_body_bullet.cpp
+++ b/modules/bullet/rigid_body_bullet.cpp
@@ -179,7 +179,7 @@ int BulletPhysicsDirectBodyState::get_contact_collider_shape(int p_contact_idx)
 }
 
 Vector3 BulletPhysicsDirectBodyState::get_contact_collider_velocity_at_position(int p_contact_idx) const {
-	RigidBodyBullet::CollisionData &colDat = body->collisions[p_contact_idx];
+	RigidBodyBullet::CollisionData &colDat = body->collisions.write[p_contact_idx];
 
 	btVector3 hitLocation;
 	G_TO_B(colDat.hitLocalLocation, hitLocation);
@@ -224,8 +224,8 @@ void RigidBodyBullet::KinematicUtilities::copyAllOwnerShapes() {
 			continue;
 		}
 
-		shapes[i].transform = shape_wrapper->transform;
-		shapes[i].transform.getOrigin() *= owner_scale;
+		shapes.write[i].transform = shape_wrapper->transform;
+		shapes.write[i].transform.getOrigin() *= owner_scale;
 		switch (shape_wrapper->shape->get_type()) {
 			case PhysicsServer::SHAPE_SPHERE:
 			case PhysicsServer::SHAPE_BOX:
@@ -233,11 +233,11 @@ void RigidBodyBullet::KinematicUtilities::copyAllOwnerShapes() {
 			case PhysicsServer::SHAPE_CYLINDER:
 			case PhysicsServer::SHAPE_CONVEX_POLYGON:
 			case PhysicsServer::SHAPE_RAY: {
-				shapes[i].shape = static_cast<btConvexShape *>(shape_wrapper->shape->create_bt_shape(owner_scale * shape_wrapper->scale, safe_margin));
+				shapes.write[i].shape = static_cast<btConvexShape *>(shape_wrapper->shape->create_bt_shape(owner_scale * shape_wrapper->scale, safe_margin));
 			} break;
 			default:
 				WARN_PRINT("This shape is not supported to be kinematic!");
-				shapes[i].shape = NULL;
+				shapes.write[i].shape = NULL;
 		}
 	}
 }
@@ -245,7 +245,7 @@ void RigidBodyBullet::KinematicUtilities::copyAllOwnerShapes() {
 void RigidBodyBullet::KinematicUtilities::just_delete_shapes(int new_size) {
 	for (int i = shapes.size() - 1; 0 <= i; --i) {
 		if (shapes[i].shape) {
-			bulletdelete(shapes[i].shape);
+			bulletdelete(shapes.write[i].shape);
 		}
 	}
 	shapes.resize(new_size);
@@ -287,7 +287,7 @@ RigidBodyBullet::RigidBodyBullet() :
 
 	areasWhereIam.resize(maxAreasWhereIam);
 	for (int i = areasWhereIam.size() - 1; 0 <= i; --i) {
-		areasWhereIam[i] = NULL;
+		areasWhereIam.write[i] = NULL;
 	}
 	btBody->setSleepingThresholds(0.2, 0.2);
 }
@@ -413,7 +413,7 @@ bool RigidBodyBullet::add_collision_object(RigidBodyBullet *p_otherObject, const
 		return false;
 	}
 
-	CollisionData &cd = collisions[collisionsCount];
+	CollisionData &cd = collisions.write[collisionsCount];
 	cd.hitLocalLocation = p_hitLocalLocation;
 	cd.otherObject = p_otherObject;
 	cd.hitWorldLocation = p_hitWorldLocation;
@@ -817,15 +817,15 @@ void RigidBodyBullet::on_enter_area(AreaBullet *p_area) {
 
 		if (NULL == areasWhereIam[i]) {
 			// This area has the highest priority
-			areasWhereIam[i] = p_area;
+			areasWhereIam.write[i] = p_area;
 			break;
 		} else {
 			if (areasWhereIam[i]->get_spOv_priority() > p_area->get_spOv_priority()) {
 				// The position was found, just shift all elements
 				for (int j = i; j < areaWhereIamCount; ++j) {
-					areasWhereIam[j + 1] = areasWhereIam[j];
+					areasWhereIam.write[j + 1] = areasWhereIam[j];
 				}
-				areasWhereIam[i] = p_area;
+				areasWhereIam.write[i] = p_area;
 				break;
 			}
 		}
@@ -849,7 +849,7 @@ void RigidBodyBullet::on_exit_area(AreaBullet *p_area) {
 		if (p_area == areasWhereIam[i]) {
 			// The area was fount, just shift down all elements
 			for (int j = i; j < areaWhereIamCount; ++j) {
-				areasWhereIam[j] = areasWhereIam[j + 1];
+				areasWhereIam.write[j] = areasWhereIam[j + 1];
 			}
 			wasTheAreaFound = true;
 			break;
@@ -862,7 +862,7 @@ void RigidBodyBullet::on_exit_area(AreaBullet *p_area) {
 		}
 
 		--areaWhereIamCount;
-		areasWhereIam[areaWhereIamCount] = NULL; // Even if this is not required, I clear the last element to be safe
+		areasWhereIam.write[areaWhereIamCount] = NULL; // Even if this is not required, I clear the last element to be safe
 		if (PhysicsServer::AREA_SPACE_OVERRIDE_DISABLED != p_area->get_spOv_mode()) {
 			scratch_space_override_modificator();
 		}
diff --git a/modules/bullet/shape_bullet.cpp b/modules/bullet/shape_bullet.cpp
index 92e7c2df98..e4c1a5f9b5 100644
--- a/modules/bullet/shape_bullet.cpp
+++ b/modules/bullet/shape_bullet.cpp
@@ -304,7 +304,7 @@ void ConvexPolygonShapeBullet::get_vertices(Vector<Vector3> &out_vertices) {
 	const int n_of_vertices = vertices.size();
 	out_vertices.resize(n_of_vertices);
 	for (int i = n_of_vertices - 1; 0 <= i; --i) {
-		B_TO_G(vertices[i], out_vertices[i]);
+		B_TO_G(vertices[i], out_vertices.write[i]);
 	}
 }
 
diff --git a/modules/bullet/soft_body_bullet.cpp b/modules/bullet/soft_body_bullet.cpp
index b3680d58db..1686a6e87e 100644
--- a/modules/bullet/soft_body_bullet.cpp
+++ b/modules/bullet/soft_body_bullet.cpp
@@ -90,7 +90,7 @@ void SoftBodyBullet::update_visual_server(SoftBodyVisualServerHandler *p_visual_
 	const btSoftBody::tNodeArray &nodes(bt_soft_body->m_nodes);
 	const int nodes_count = nodes.size();
 
-	Vector<int> *vs_indices;
+	const Vector<int> *vs_indices;
 	const void *vertex_position;
 	const void *vertex_normal;
 
@@ -359,7 +359,7 @@ void SoftBodyBullet::set_trimesh_body_shape(PoolVector<int> p_indices, PoolVecto
 					indices_table.push_back(Vector<int>());
 				}
 
-				indices_table[vertex_id].push_back(vs_vertex_index);
+				indices_table.write[vertex_id].push_back(vs_vertex_index);
 				vs_indices_to_physics_table.push_back(vertex_id);
 			}
 		}
@@ -374,9 +374,9 @@ void SoftBodyBullet::set_trimesh_body_shape(PoolVector<int> p_indices, PoolVecto
 			PoolVector<Vector3>::Read p_vertices_read = p_vertices.read();
 
 			for (int i = 0; i < indices_map_size; ++i) {
-				bt_vertices[3 * i + 0] = p_vertices_read[indices_table[i][0]].x;
-				bt_vertices[3 * i + 1] = p_vertices_read[indices_table[i][0]].y;
-				bt_vertices[3 * i + 2] = p_vertices_read[indices_table[i][0]].z;
+				bt_vertices.write[3 * i + 0] = p_vertices_read[indices_table[i][0]].x;
+				bt_vertices.write[3 * i + 1] = p_vertices_read[indices_table[i][0]].y;
+				bt_vertices.write[3 * i + 2] = p_vertices_read[indices_table[i][0]].z;
 			}
 		}
 
@@ -390,9 +390,9 @@ void SoftBodyBullet::set_trimesh_body_shape(PoolVector<int> p_indices, PoolVecto
 			PoolVector<int>::Read p_indices_read = p_indices.read();
 
 			for (int i = 0; i < triangles_size; ++i) {
-				bt_triangles[3 * i + 0] = vs_indices_to_physics_table[p_indices_read[3 * i + 2]];
-				bt_triangles[3 * i + 1] = vs_indices_to_physics_table[p_indices_read[3 * i + 1]];
-				bt_triangles[3 * i + 2] = vs_indices_to_physics_table[p_indices_read[3 * i + 0]];
+				bt_triangles.write[3 * i + 0] = vs_indices_to_physics_table[p_indices_read[3 * i + 2]];
+				bt_triangles.write[3 * i + 1] = vs_indices_to_physics_table[p_indices_read[3 * i + 1]];
+				bt_triangles.write[3 * i + 2] = vs_indices_to_physics_table[p_indices_read[3 * i + 0]];
 			}
 		}
 
diff --git a/modules/bullet/space_bullet.cpp b/modules/bullet/space_bullet.cpp
index 132c3739d6..1ef631c916 100644
--- a/modules/bullet/space_bullet.cpp
+++ b/modules/bullet/space_bullet.cpp
@@ -686,7 +686,7 @@ void SpaceBullet::check_ghost_overlaps() {
 
 		/// 1. Reset all states
 		for (i = area->overlappingObjects.size() - 1; 0 <= i; --i) {
-			AreaBullet::OverlappingObjectData &otherObj = area->overlappingObjects[i];
+			AreaBullet::OverlappingObjectData &otherObj = area->overlappingObjects.write[i];
 			// This check prevent the overwrite of ENTER state
 			// if this function is called more times before dispatchCallbacks
 			if (otherObj.state != AreaBullet::OVERLAP_STATE_ENTER) {
diff --git a/modules/bullet/space_bullet.h b/modules/bullet/space_bullet.h
index 006c6462cf..6b86fc2f03 100644
--- a/modules/bullet/space_bullet.h
+++ b/modules/bullet/space_bullet.h
@@ -164,7 +164,7 @@ public:
 		contactDebugCount = 0;
 	}
 	_FORCE_INLINE_ void add_debug_contact(const Vector3 &p_contact) {
-		if (contactDebugCount < contactDebug.size()) contactDebug[contactDebugCount++] = p_contact;
+		if (contactDebugCount < contactDebug.size()) contactDebug.write[contactDebugCount++] = p_contact;
 	}
 	_FORCE_INLINE_ Vector<Vector3> get_debug_contacts() { return contactDebug; }
 	_FORCE_INLINE_ int get_debug_contact_count() { return contactDebugCount; }