Do not hold a reference to the Style at the [Live|Vector]TileData

Layers are added and removed dynamically on the Map thread when we use shape
annotations and we are iterating style.layers on the Worker thread without
any lock.

Now when we create a [Live|Vector]TileData at the Map thread we give it
a layers list (instead of the Style) and [Live|Vector]TileData will ultimately
make a copy of this list (on the Map thread, so no concurrency with
adding shape annotations).

The copy should be relatively cheap because we are using a shared pointer
for storing the layers on the list.

1 files changed, 8 insertions, 8 deletions

diff --git a/src/mbgl/map/vector_tile_data.cpp b/src/mbgl/map/vector_tile_data.cpp
index 6dc6e8e9b3..017d3ecb7c 100644
--- a/src/mbgl/map/vector_tile_data.cpp
+++ b/src/mbgl/map/vector_tile_data.cpp
@@ -9,12 +9,12 @@
 #include <mbgl/util/pbf.hpp>
 #include <mbgl/util/worker.hpp>
 #include <mbgl/util/work_request.hpp>
-#include <mbgl/style/style.hpp>
 
 using namespace mbgl;
 
 VectorTileData::VectorTileData(const TileID& id_,
-                               Style& style_,
+                               const std::vector<util::ptr<StyleLayer>>& layers_,
+                               Worker& workers_,
                                GlyphAtlas& glyphAtlas_,
                                GlyphStore& glyphStore_,
                                SpriteAtlas& spriteAtlas_,
@@ -23,11 +23,12 @@ VectorTileData::VectorTileData(const TileID& id_,
                                float angle,
                                bool collisionDebug)
     : TileData(id_, source_),
+      layers(layers_),
+      workers(workers_),
       glyphAtlas(glyphAtlas_),
       glyphStore(glyphStore_),
       spriteAtlas(spriteAtlas_),
       sprite(sprite_),
-      style(style_),
       collision(std::make_unique<CollisionTile>(id_.z, 4096, source_.tile_size * id.overscaling, angle, collisionDebug)),
       lastAngle(angle),
       currentAngle(angle) {
@@ -51,7 +52,7 @@ void VectorTileData::parse() {
         // is going to be discarded afterwards.
         VectorTile vectorTile(pbf((const uint8_t *)data.data(), data.size()));
         const VectorTile* vt = &vectorTile;
-        TileParser parser(*vt, *this, style, glyphAtlas, glyphStore, spriteAtlas, sprite);
+        TileParser parser(*vt, *this, layers, glyphAtlas, glyphStore, spriteAtlas, sprite);
         parser.parse();
 
         if (getState() == State::obsolete) {
@@ -128,15 +129,14 @@ void VectorTileData::redoPlacement(float angle, bool collisionDebug) {
         currentCollisionDebug = collisionDebug;
 
         auto callback = std::bind(&VectorTileData::endRedoPlacement, this);
-        workRequest = style.workers.send([this, angle, collisionDebug] { workerRedoPlacement(angle, collisionDebug); }, callback);
-
+        workRequest = workers.send([this, angle, collisionDebug] { workerRedoPlacement(angle, collisionDebug); }, callback);
     }
 }
 
 void VectorTileData::workerRedoPlacement(float angle, bool collisionDebug) {
     collision->reset(angle, 0);
     collision->setDebug(collisionDebug);
-    for (const auto& layer_desc : style.layers) {
+    for (const auto& layer_desc : layers) {
         auto bucket = getBucket(*layer_desc);
         if (bucket) {
             bucket->placeFeatures();
@@ -145,7 +145,7 @@ void VectorTileData::workerRedoPlacement(float angle, bool collisionDebug) {
 }
 
 void VectorTileData::endRedoPlacement() {
-    for (const auto& layer_desc : style.layers) {
+    for (const auto& layer_desc : layers) {
         auto bucket = getBucket(*layer_desc);
         if (bucket) {
             bucket->swapRenderData();