Clear image cache when tabbing out of canvas

src/MainProgram.cpp

@@ -96,6 +96,8 @@ void MainProgram::update() {
 
     std::shared_ptr<World> oldWorld = world;
     world = worlds[worldIndex];
+    if(oldWorld != world && oldWorld)
+        oldWorld->on_switch_out();
 
     deltaTime.update_time_since();
     deltaTime.update_time_point();

src/ResourceDisplay/ImageResourceDisplay.cpp

@@ -287,6 +287,20 @@ ResourceDisplay::Type ImageResourceDisplay::get_type() const {
     return ResourceDisplay::Type::IMAGE;
 }
 
+void ImageResourceDisplay::clear_cache() {
+    if(loadThread) {
+        shutdownLoadThread = true;
+        loadThread->join();
+        loadThread = nullptr;
+    }
+    for(auto& frame : frames) {
+        for(auto& mipmap : frame.mipmapLevels)
+            mipmap = nullptr;
+    }
+    for(auto& mipmapStatus : mipmapLevelsStatus)
+        mipmapStatus = MipmapLevelStatus::UNALLOCATED;
+}
+
 ImageResourceDisplay::~ImageResourceDisplay() {
     if(loadThread) {
         shutdownLoadThread = true;

src/ResourceDisplay/ImageResourceDisplay.hpp

@@ -16,6 +16,7 @@ class ImageResourceDisplay : public ResourceDisplay {
         virtual float get_dimension_scale() const override;
         virtual Type get_type() const override;
         virtual void camera_view_update(const CoordSpaceHelper& compCoords, const SCollision::AABB<WorldScalar>& compAABB, const DrawData& drawData, const SkRect& imRect) override;
+        virtual void clear_cache() override;
         virtual ~ImageResourceDisplay() override;
 
         static int IMAGE_LOAD_THREAD_COUNT_MAX;

src/ResourceDisplay/ResourceDisplay.cpp

@@ -3,4 +3,7 @@
 void ResourceDisplay::camera_view_update(const CoordSpaceHelper& compCoords, const SCollision::AABB<WorldScalar>& compAABB, const DrawData& drawData, const SkRect& imRect) {
 }
 
+void ResourceDisplay::clear_cache() {
+}
+
 ResourceDisplay::~ResourceDisplay() {}

src/ResourceDisplay/ResourceDisplay.hpp

@@ -27,5 +27,6 @@ class ResourceDisplay {
         virtual float get_dimension_scale() const = 0;
         virtual Type get_type() const = 0;
         virtual void camera_view_update(const CoordSpaceHelper& compCoords, const SCollision::AABB<WorldScalar>& compAABB, const DrawData& drawData, const SkRect& imRect);
+        virtual void clear_cache();
         virtual ~ResourceDisplay();
 };

src/ResourceManager.cpp

@@ -200,3 +200,8 @@ void ResourceManager::save_file(cereal::PortableBinaryOutputArchive& a) const {
     });
     a(strippedResources);
 }
+
+void ResourceManager::clear_display_cache() {
+    for(auto& [id, display] : displays)
+        display->clear_cache();
+}

src/ResourceManager.hpp

@@ -33,6 +33,7 @@ class ResourceManager {
         const std::vector<NetworkingObjects::NetObjOwnerPtr<ResourceData>>& resource_list();
         float get_resource_retrieval_progress(const NetworkingObjects::NetObjID& id);
         std::unordered_map<NetworkingObjects::NetObjID, ResourceData> copy_resource_set_to_map(const std::unordered_set<NetworkingObjects::NetObjID>& resourceSet) const;
+        void clear_display_cache();
 
         void load_file(cereal::PortableBinaryInputArchive& a, VersionNumber version);
         void save_file(cereal::PortableBinaryOutputArchive& a) const;

src/World.cpp

@@ -244,6 +244,10 @@ void World::unfocus_update() {
         return;
 }
 
+void World::on_switch_out() {
+    rMan.clear_display_cache();
+}
+
 void World::send_chat_message(const std::string& message) {
     if(!clientStillConnecting)
         ownClientData->send_chat_message(ownClientData, *this, message);

src/World.hpp

@@ -66,6 +66,7 @@ class World {
 
         void focus_update();
         void unfocus_update();
+        void on_switch_out();
 
         void draw(SkCanvas* canvas);
         void early_destroy();