1 files changed, 229 insertions, 0 deletions
diff --git a/Source/Core/VideoCommon/Assets/CustomResourceManager.cpp b/Source/Core/VideoCommon/Assets/CustomResourceManager.cpp
new file mode 100644
index 0000000000..f2af4ccbea
--- /dev/null
+++ b/Source/Core/VideoCommon/Assets/CustomResourceManager.cpp
@@ -0,0 +1,229 @@
+// Copyright 2025 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "VideoCommon/Assets/CustomResourceManager.h"
+
+#include "Common/Logging/Log.h"
+#include "Common/MemoryUtil.h"
+
+#include "UICommon/UICommon.h"
+
+#include "VideoCommon/Assets/CustomAsset.h"
+#include "VideoCommon/Assets/TextureAsset.h"
+#include "VideoCommon/VideoEvents.h"
+
+namespace VideoCommon
+{
+void CustomResourceManager::Initialize()
+{
+  // Use half of available system memory but leave at least 2GiB unused for system stability.
+  constexpr size_t must_keep_unused = 2 * size_t(1024 * 1024 * 1024);
+
+  const size_t sys_mem = Common::MemPhysical();
+  const size_t keep_unused_mem = std::max(sys_mem / 2, std::min(sys_mem, must_keep_unused));
+
+  m_max_ram_available = sys_mem - keep_unused_mem;
+
+  if (m_max_ram_available == 0)
+    ERROR_LOG_FMT(VIDEO, "Not enough system memory for custom resources.");
+
+  m_asset_loader.Initialize();
+
+  m_xfb_event =
+      AfterFrameEvent::Register([this](Core::System&) { XFBTriggered(); }, "CustomResourceManager");
+}
+
+void CustomResourceManager::Shutdown()
+{
+  Reset();
+
+  m_asset_loader.Shutdown();
+}
+
+void CustomResourceManager::Reset()
+{
+  m_asset_loader.Reset(true);
+
+  m_active_assets = {};
+  m_pending_assets = {};
+  m_asset_handle_to_data.clear();
+  m_asset_id_to_handle.clear();
+  m_texture_data_asset_cache.clear();
+  m_dirty_assets.clear();
+  m_ram_used = 0;
+}
+
+void CustomResourceManager::MarkAssetDirty(const CustomAssetLibrary::AssetID& asset_id)
+{
+  std::lock_guard guard(m_dirty_mutex);
+  m_dirty_assets.insert(asset_id);
+}
+
+CustomResourceManager::TextureTimePair CustomResourceManager::GetTextureDataFromAsset(
+    const CustomAssetLibrary::AssetID& asset_id,
+    std::shared_ptr<VideoCommon::CustomAssetLibrary> library)
+{
+  auto& resource = m_texture_data_asset_cache[asset_id];
+  if (resource.asset_data != nullptr &&
+      resource.asset_data->load_status == AssetData::LoadStatus::ResourceDataAvailable)
+  {
+    m_active_assets.MakeAssetHighestPriority(resource.asset->GetHandle(), resource.asset);
+    return {resource.texture_data, resource.asset->GetLastLoadedTime()};
+  }
+
+  // If there is an error, don't try and load again until the error is fixed
+  if (resource.asset_data != nullptr && resource.asset_data->has_load_error)
+    return {};
+
+  LoadTextureDataAsset(asset_id, std::move(library), &resource);
+  m_active_assets.MakeAssetHighestPriority(resource.asset->GetHandle(), resource.asset);
+
+  return {};
+}
+
+void CustomResourceManager::LoadTextureDataAsset(
+    const CustomAssetLibrary::AssetID& asset_id,
+    std::shared_ptr<VideoCommon::CustomAssetLibrary> library, InternalTextureDataResource* resource)
+{
+  if (!resource->asset)
+  {
+    resource->asset =
+        CreateAsset<TextureAsset>(asset_id, AssetData::AssetType::TextureData, std::move(library));
+    resource->asset_data = &m_asset_handle_to_data[resource->asset->GetHandle()];
+  }
+
+  auto texture_data = resource->asset->GetData();
+  if (!texture_data || resource->asset_data->load_status == AssetData::LoadStatus::PendingReload)
+  {
+    // Tell the system we are still interested in loading this asset
+    const auto asset_handle = resource->asset->GetHandle();
+    m_pending_assets.MakeAssetHighestPriority(asset_handle,
+                                              m_asset_handle_to_data[asset_handle].asset.get());
+  }
+  else if (resource->asset_data->load_status == AssetData::LoadStatus::LoadFinished)
+  {
+    resource->texture_data = std::move(texture_data);
+    resource->asset_data->load_status = AssetData::LoadStatus::ResourceDataAvailable;
+  }
+}
+
+void CustomResourceManager::XFBTriggered()
+{
+  ProcessDirtyAssets();
+  ProcessLoadedAssets();
+
+  if (m_ram_used > m_max_ram_available)
+  {
+    RemoveAssetsUntilBelowMemoryLimit();
+  }
+
+  if (m_pending_assets.IsEmpty())
+    return;
+
+  if (m_ram_used > m_max_ram_available)
+    return;
+
+  const u64 allowed_memory = m_max_ram_available - m_ram_used;
+  m_asset_loader.ScheduleAssetsToLoad(m_pending_assets.Elements(), allowed_memory);
+}
+
+void CustomResourceManager::ProcessDirtyAssets()
+{
+  decltype(m_dirty_assets) dirty_assets;
+
+  if (const auto lk = std::unique_lock{m_dirty_mutex, std::try_to_lock})
+    std::swap(dirty_assets, m_dirty_assets);
+
+  const auto now = CustomAsset::ClockType::now();
+  for (const auto& asset_id : dirty_assets)
+  {
+    if (const auto it = m_asset_id_to_handle.find(asset_id); it != m_asset_id_to_handle.end())
+    {
+      const auto asset_handle = it->second;
+      AssetData& asset_data = m_asset_handle_to_data[asset_handle];
+      asset_data.load_status = AssetData::LoadStatus::PendingReload;
+      asset_data.load_request_time = now;
+
+      // Asset was reloaded, clear any errors we might have
+      asset_data.has_load_error = false;
+
+      m_pending_assets.InsertAsset(it->second, asset_data.asset.get());
+
+      DEBUG_LOG_FMT(VIDEO, "Dirty asset pending reload: {}", asset_data.asset->GetAssetId());
+    }
+  }
+}
+
+void CustomResourceManager::ProcessLoadedAssets()
+{
+  const auto load_results = m_asset_loader.TakeLoadResults();
+
+  // Update the ram with the change in memory from the loader
+  //
+  // Note: Assets with outstanding reload requests will have
+  // two copies in memory temporarily (the old data stored in
+  // the asset shared_ptr that the resource manager owns, and
+  // the new data loaded from the loader in the asset's shared_ptr)
+  // This temporary duplication will not be reflected in the
+  // resource manager's ram used
+  m_ram_used += load_results.change_in_memory;
+
+  for (const auto& [handle, load_successful] : load_results.asset_handles)
+  {
+    AssetData& asset_data = m_asset_handle_to_data[handle];
+
+    // If we have a reload request that is newer than our loaded time
+    // we need to wait for another reload.
+    if (asset_data.load_request_time > asset_data.asset->GetLastLoadedTime())
+      continue;
+
+    m_pending_assets.RemoveAsset(handle);
+
+    asset_data.load_request_time = {};
+    if (!load_successful)
+    {
+      asset_data.has_load_error = true;
+    }
+    else
+    {
+      m_active_assets.InsertAsset(handle, asset_data.asset.get());
+      asset_data.load_status = AssetData::LoadStatus::LoadFinished;
+    }
+  }
+}
+
+void CustomResourceManager::RemoveAssetsUntilBelowMemoryLimit()
+{
+  const u64 threshold_ram = m_max_ram_available * 8 / 10;
+
+  if (m_ram_used > threshold_ram)
+  {
+    INFO_LOG_FMT(VIDEO, "Memory usage over threshold: {}", UICommon::FormatSize(m_ram_used));
+  }
+
+  // Clear out least recently used resources until
+  // we get safely in our threshold
+  while (m_ram_used > threshold_ram && m_active_assets.Size() > 0)
+  {
+    auto* const asset = m_active_assets.RemoveLowestPriorityAsset();
+
+    AssetData& asset_data = m_asset_handle_to_data[asset->GetHandle()];
+
+    // Remove the resource manager's cached entry with its asset data
+    if (asset_data.type == AssetData::AssetType::TextureData)
+    {
+      m_texture_data_asset_cache.erase(asset->GetAssetId());
+    }
+    // Remove the asset's copy
+    const std::size_t bytes_unloaded = asset_data.asset->Unload();
+    m_ram_used -= bytes_unloaded;
+
+    asset_data.load_status = AssetData::LoadStatus::Unloaded;
+    asset_data.load_request_time = {};
+
+    INFO_LOG_FMT(VIDEO, "Unloading asset: {} ({})", asset_data.asset->GetAssetId(),
+                 UICommon::FormatSize(bytes_unloaded));
+  }
+}
+
+}  // namespace VideoCommon