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.

1 files changed, 1 insertions, 1 deletions

diff --git a/scene/resources/scene_format_text.cpp b/scene/resources/scene_format_text.cpp
index 9df117d09c..fd9989fe72 100644
--- a/scene/resources/scene_format_text.cpp
+++ b/scene/resources/scene_format_text.cpp
@@ -1523,7 +1523,7 @@ Error ResourceFormatSaverTextInstance::save(const String &p_path, const RES &p_r
 
 	for (Map<RES, int>::Element *E = external_resources.front(); E; E = E->next()) {
 
-		sorted_er[E->get()] = E->key();
+		sorted_er.write[E->get()] = E->key();
 	}
 
 	for (int i = 0; i < sorted_er.size(); i++) {