allow persistently preloading assets

2 files changed, 37 insertions, 13 deletions

diff --git a/source/base/StarAssets.cpp b/source/base/StarAssets.cpp
index 8471a0c..7fad6be 100644
--- a/source/base/StarAssets.cpp
+++ b/source/base/StarAssets.cpp
@@ -24,6 +24,14 @@
 
 namespace Star {
 
+EnumMap<AssetType> const AssetTypeNames{
+    {AssetType::Json, "json"},
+    {AssetType::Image, "image"},
+    {AssetType::Audio, "audio"},
+    {AssetType::Font, "font"},
+    {AssetType::Bytes, "bytes"}
+};
+    
 static void validateBasePath(std::string_view const& basePath) {
   if (basePath.empty() || basePath[0] != '/')
     throw AssetException(strf("Path '{}' must be absolute", basePath));
@@ -353,6 +361,20 @@ Assets::Assets(Settings settings, StringList assetSources) {
   int workerPoolSize = m_settings.workerPoolSize;
   for (int i = 0; i < workerPoolSize; i++)
     m_workerThreads.append(Thread::invoke("Assets::workerMain", mem_fn(&Assets::workerMain), this));
+  
+  // preload.config contains an array of files which will be loaded and then told to persist
+  Json preload = json("/preload.config");
+  Logger::info("Preloading assets");
+  for (auto script : preload.iterateArray()) {
+    auto type = AssetTypeNames.getLeft(script.getString("type"));
+    auto path = script.getString("path");
+    auto components = AssetPath::split(path);
+    validatePath(components, type == AssetType::Json, type == AssetType::Image);
+
+    auto asset = getAsset(AssetId{type, std::move(components)});
+    // make this asset never unload
+    asset->forcePersist = true;
+  }
 }
 
 Assets::~Assets() {
@@ -626,23 +648,23 @@ size_t Assets::AssetIdHash::operator()(AssetId const& id) const {
 }
 
 bool Assets::JsonData::shouldPersist() const {
-  return !json.unique();
+  return forcePersist || !json.unique();
 }
 
 bool Assets::ImageData::shouldPersist() const {
-  return !alias && !image.unique();
+  return forcePersist || !alias && !image.unique();
 }
 
 bool Assets::AudioData::shouldPersist() const {
-  return !audio.unique();
+  return forcePersist || !audio.unique();
 }
 
 bool Assets::FontData::shouldPersist() const {
-  return !font.unique();
+  return forcePersist || !font.unique();
 }
 
 bool Assets::BytesData::shouldPersist() const {
-  return !bytes.unique();
+  return forcePersist || !bytes.unique();
 }
 
 FramesSpecification Assets::parseFramesSpecification(Json const& frameConfig, String path) {
diff --git a/source/base/StarAssets.hpp b/source/base/StarAssets.hpp
index 6ffcb05..e848410 100644
--- a/source/base/StarAssets.hpp
+++ b/source/base/StarAssets.hpp
@@ -38,6 +38,15 @@ struct FramesSpecification {
   StringMap<String> aliases;
 };
 
+enum class AssetType {
+  Json,
+  Image,
+  Audio,
+  Font,
+  Bytes
+};
+extern EnumMap<AssetType> const AssetTypeNames;
+
 // The assets system can load image, font, json, and data assets from a set of
 // sources.  Each source is either a directory on the filesystem or a single
 // packed asset file.
@@ -71,14 +80,6 @@ public:
     StringList digestIgnore;
   };
 
-    enum class AssetType {
-    Json,
-    Image,
-    Audio,
-    Font,
-    Bytes
-  };
-
   enum class QueuePriority {
     None,
     Working,
@@ -107,6 +108,7 @@ public:
 
     double time = 0.0;
     bool needsPostProcessing = false;
+    bool forcePersist = false;
   };
 
   struct JsonData : AssetData {