[core] remove TileData::State::loaded

src/mbgl/source/source.cpp

@@ -63,7 +63,7 @@ bool Source::isLoaded() const {
     if (!loaded) return false;
 
     for (const auto& pair : tileDataMap) {
-        if (pair.second->getState() != TileData::State::parsed) {
+        if (!pair.second->isComplete()) {
             return false;
         }
     }

src/mbgl/tile/raster_tile_data.cpp

@@ -18,8 +18,6 @@ RasterTileData::RasterTileData(const OverscaledTileID& id_,
     : TileData(id_),
       texturePool(texturePool_),
       worker(worker_) {
-    state = State::loading;
-
     const Resource resource =
         Resource::tile(urlTemplate, pixelRatio, id.canonical.x, id.canonical.y, id.canonical.z);
     req = fileSource.request(resource, [callback, this](Response res) {
@@ -39,17 +37,9 @@ RasterTileData::RasterTileData(const OverscaledTileID& id_,
             modified = res.modified;
             expires = res.expires;
 
-            // Only overwrite the state when we didn't have a previous tile.
-            if (state == State::loading) {
-                state = State::loaded;
-            }
-
             workRequest.reset();
             workRequest = worker.parseRasterTile(std::make_unique<RasterBucket>(texturePool), res.data, [this, callback] (RasterTileParseResult result) {
                 workRequest.reset();
-                if (state != State::loaded) {
-                    return;
-                }
 
                 std::exception_ptr error;
                 if (result.is<std::unique_ptr<Bucket>>()) {

src/mbgl/tile/tile_data.cpp

@@ -6,16 +6,14 @@ namespace mbgl {
 
 TileData::TileData(const OverscaledTileID& id_)
     : id(id_),
-      state(State::initial) {
+      state(State::loading) {
 }
 
 TileData::~TileData() = default;
 
 const char* TileData::StateToString(const State state) {
     switch (state) {
-        case TileData::State::initial: return "initial";
         case TileData::State::loading : return "loading";
-        case TileData::State::loaded : return "loaded";
         case TileData::State::obsolete : return "obsolete";
         case TileData::State::parsed : return "parsed";
         case TileData::State::partial : return "partial";

src/mbgl/tile/tile_data.hpp

@@ -24,16 +24,10 @@ class TransformState;
 
 class TileData : private util::noncopyable {
 public:
-    // initial:
-    //   Initial state, only used when the TileData object is created.
-    //
     // loading:
     //   A request to the FileSource was made for the actual tile data and TileData
     //   is waiting for it to arrive.
     //
-    // loaded:
-    //   The actual tile data has arrived and the tile can be parsed.
-    //
     // partial:
     //   TileData is partially parsed, some buckets are still waiting for dependencies
     //   to arrive, but it is good for rendering. Partial tiles can also be re-parsed,
@@ -47,9 +41,7 @@ public:
     //   The TileData can go to obsolete from any state, due to parsing or loading error,
     //   request cancellation or because the tile is no longer in use.
     enum class State {
-        initial,
         loading,
-        loaded,
         partial,
         parsed,
         obsolete
@@ -82,6 +74,10 @@ public:
         return state == State::partial || state == State::parsed;
     }
 
+    bool isComplete() const {
+        return state == State::parsed;
+    }
+
     State getState() const {
         return state;
     }

src/mbgl/tile/vector_tile_data.cpp

@@ -29,7 +29,6 @@ VectorTileData::VectorTileData(const OverscaledTileID& id_,
                  mode_),
       monitor(std::move(monitor_))
 {
-    state = State::loading;
     tileRequest = monitor->monitorTile([callback, this](std::exception_ptr err,
                                                         std::unique_ptr<GeometryTile> tile,
                                                         optional<Timestamp> modified_,
@@ -51,9 +50,9 @@ VectorTileData::VectorTileData(const OverscaledTileID& id_,
             return;
         }
 
-        if (state == State::loading) {
-            state = State::loaded;
-        } else if (isRenderable()) {
+        // Mark the tile as pending again if it was complete before to prevent signaling a complete
+        // state despite pending parse operations.
+        if (isComplete()) {
             state = State::partial;
         }
 
@@ -80,7 +79,7 @@ VectorTileData::VectorTileData(const OverscaledTileID& id_,
                 // existing buckets in case we got a refresh parse.
                 buckets = std::move(resultBuckets.buckets);
 
-                if (state == State::parsed) {
+                if (isComplete()) {
                     featureIndex = std::move(resultBuckets.featureIndex);
                     geometryTile = std::move(resultBuckets.geometryTile);
                 }
@@ -127,7 +126,7 @@ bool VectorTileData::parsePending(std::function<void(std::exception_ptr)> callba
             // place again in case the configuration has changed.
             placedConfig = config;
 
-            if (state == State::parsed) {
+            if (isComplete()) {
                 featureIndex = std::move(resultBuckets.featureIndex);
                 geometryTile = std::move(resultBuckets.geometryTile);
             }