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, 6 insertions, 6 deletions

diff --git a/scene/animation/animation_cache.cpp b/scene/animation/animation_cache.cpp
index 949a0be3bc..756907c41c 100644
--- a/scene/animation/animation_cache.cpp
+++ b/scene/animation/animation_cache.cpp
@@ -43,7 +43,7 @@ void AnimationCache::_node_exit_tree(Node *p_node) {
 		if (path_cache[i].node != p_node)
 			continue;
 
-		path_cache[i].valid = false; //invalidate path cache
+		path_cache.write[i].valid = false; //invalidate path cache
 	}
 }
 
@@ -196,7 +196,7 @@ void AnimationCache::set_track_transform(int p_idx, const Transform &p_transform
 
 	ERR_FAIL_COND(!cache_valid);
 	ERR_FAIL_INDEX(p_idx, path_cache.size());
-	Path &p = path_cache[p_idx];
+	Path &p = path_cache.write[p_idx];
 	if (!p.valid)
 		return;
 
@@ -217,7 +217,7 @@ void AnimationCache::set_track_value(int p_idx, const Variant &p_value) {
 
 	ERR_FAIL_COND(!cache_valid);
 	ERR_FAIL_INDEX(p_idx, path_cache.size());
-	Path &p = path_cache[p_idx];
+	Path &p = path_cache.write[p_idx];
 	if (!p.valid)
 		return;
 
@@ -232,7 +232,7 @@ void AnimationCache::call_track(int p_idx, const StringName &p_method, const Var
 
 	ERR_FAIL_COND(!cache_valid);
 	ERR_FAIL_INDEX(p_idx, path_cache.size());
-	Path &p = path_cache[p_idx];
+	Path &p = path_cache.write[p_idx];
 	if (!p.valid)
 		return;
 
@@ -297,11 +297,11 @@ void AnimationCache::set_all(float p_time, float p_delta) {
 						call_track(i, name, NULL, 0, err);
 					} else {
 
-						Vector<Variant *> argptrs;
+						Vector<const Variant *> argptrs;
 						argptrs.resize(args.size());
 						for (int j = 0; j < args.size(); j++) {
 
-							argptrs[j] = &args[j];
+							argptrs.write[j] = &args.write[j];
 						}
 
 						call_track(i, name, (const Variant **)&argptrs[0], args.size(), err);