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#pragma once
#include "../include/Storage.hpp"
#include "../include/MessageQueue.hpp"
#include "../include/FileAnalyzer.hpp"
#include "../include/AsyncTask.hpp"
#include <mglpp/system/vec.hpp>
#include <mglpp/graphics/Texture.hpp>
#include <mglpp/graphics/Image.hpp>
#include <mglpp/system/Clock.hpp>
#include <string>
#include <memory>
#include <unordered_map>
namespace QuickMedia {
enum class LoadingState {
NOT_LOADED,
LOADING,
READY_TO_LOAD,
FINISHED_LOADING,
APPLIED_TO_TEXTURE
};
struct ThumbnailData {
LoadingState loading_state = LoadingState::NOT_LOADED;
mgl::Texture texture;
std::unique_ptr<mgl::Image> image; // Set in another thread. This should be .reset after loading it into |texture|, to save memory
size_t counter = 0;
Path thumbnail_path;
};
struct ThumbnailLoadData {
Path path;
Path thumbnail_path;
bool local;
std::shared_ptr<ThumbnailData> thumbnail_data;
mgl::vec2i resize_target_size;
};
// If |symlink_if_no_resize| is false then a copy is made from |thumbnail_path| to |thumbnail_path_resized| instead of a symlink if |thumbnail_path| is not larger than |resize_target_size|.
// One example of why you might not want a symlink is if |thumbnail_path| is a temporary file.
bool create_thumbnail(const Path &thumbnail_path, const Path &thumbnail_path_resized, mgl::vec2i resize_target_size, ContentType content_type);
constexpr int NUM_IMAGE_DOWNLOAD_PARALLEL = 4;
constexpr int NUM_IMAGE_LOAD_PARALLEL = 4;
class AsyncImageLoader {
public:
static AsyncImageLoader& get_instance();
// Never returns nullptr. Instead check the |loading_state| of the thumbnail data to see if it has finished loading.
// This function should be called every frame for the objects that need to display this thumbnail, otherwise it can be unloaded.
// set |resize_target_size| to {0, 0} to disable resizing.
// Note: this method is not thread-safe
std::shared_ptr<ThumbnailData> get_thumbnail(const std::string &url, bool local, mgl::vec2i resize_target_size);
// Note: this should only be called once every frame.
// Note: this method is not thread-safe
void update();
private:
struct Download {
ReadProgram read_program;
int64_t download_start = 0;
Path thumbnail_path;
std::shared_ptr<ThumbnailData> thumbnail_data;
mgl::vec2i resize_target_size;
std::string url;
};
AsyncImageLoader();
~AsyncImageLoader();
AsyncImageLoader(AsyncImageLoader &other) = delete;
AsyncImageLoader& operator=(AsyncImageLoader &other) = delete;
// set |resize_target_size| to {0, 0} to disable resizing.
// Note: this method is not thread-safe
bool load_thumbnail(const std::string &url, bool local, mgl::vec2i resize_target_size, std::shared_ptr<ThumbnailData> thumbnail_data, Path &thumbnail_path);
// Returns -1 if all threads are busy
int get_free_load_index() const;
void load_create_thumbnail(const Path &thumbnail_path, const Path &thumbnail_path_resized, ThumbnailData *thumbnail_data, mgl::vec2i resize_target_size);
void process_thumbnail(ThumbnailLoadData &thumbnail_load_data);
private:
void reset_download(Download &download);
private:
std::mutex download_mutex;
// TODO: Use curl single-threaded multi-download feature instead
Download downloads[NUM_IMAGE_DOWNLOAD_PARALLEL];
AsyncTask<void> load_threads[NUM_IMAGE_LOAD_PARALLEL];
MessageQueue<ThumbnailLoadData> image_thumbnail_create_queue;
std::unordered_map<std::string, std::shared_ptr<ThumbnailData>> thumbnails;
size_t counter = 0;
};
}
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