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, 4 insertions, 4 deletions

diff --git a/editor/animation_track_editor_plugins.cpp b/editor/animation_track_editor_plugins.cpp
index d0c91f10d9..6d444c5422 100644
--- a/editor/animation_track_editor_plugins.cpp
+++ b/editor/animation_track_editor_plugins.cpp
@@ -271,8 +271,8 @@ void AnimationTrackEditAudio::draw_key(int p_index, float p_pixels_sec, int p_x,
 			float min = preview->get_min(ofs, ofs_n) * 0.5 + 0.5;
 
 			int idx = i - from_x;
-			lines[idx * 2 + 0] = Vector2(i, rect.position.y + min * rect.size.y);
-			lines[idx * 2 + 1] = Vector2(i, rect.position.y + max * rect.size.y);
+			lines.write[idx * 2 + 0] = Vector2(i, rect.position.y + min * rect.size.y);
+			lines.write[idx * 2 + 1] = Vector2(i, rect.position.y + max * rect.size.y);
 		}
 
 		Vector<Color> color;
@@ -883,8 +883,8 @@ void AnimationTrackEditTypeAudio::draw_key(int p_index, float p_pixels_sec, int
 		float min = preview->get_min(ofs, ofs_n) * 0.5 + 0.5;
 
 		int idx = i - from_x;
-		lines[idx * 2 + 0] = Vector2(i, rect.position.y + min * rect.size.y);
-		lines[idx * 2 + 1] = Vector2(i, rect.position.y + max * rect.size.y);
+		lines.write[idx * 2 + 0] = Vector2(i, rect.position.y + min * rect.size.y);
+		lines.write[idx * 2 + 1] = Vector2(i, rect.position.y + max * rect.size.y);
 	}
 
 	Vector<Color> color;