Merge pull request #219 from OpenVicProject/asset-manager-load-flags

Add AssetManager LoadFlags

3 files changed, 130 insertions, 45 deletions

diff --git a/extension/src/openvic-extension/singletons/AssetManager.cpp b/extension/src/openvic-extension/singletons/AssetManager.cpp
index 083d934..6646c8b 100644
--- a/extension/src/openvic-extension/singletons/AssetManager.cpp
+++ b/extension/src/openvic-extension/singletons/AssetManager.cpp
@@ -13,9 +13,14 @@ using OpenVic::Utilities::godot_to_std_string;
 using OpenVic::Utilities::std_to_godot_string;
 
 void AssetManager::_bind_methods() {
-	OV_BIND_METHOD(AssetManager::get_image, { "path", "cache", "flip_y" }, DEFVAL(true), DEFVAL(false));
-	OV_BIND_METHOD(AssetManager::get_texture, { "path", "flip_y" }, DEFVAL(false));
+	OV_BIND_METHOD(AssetManager::get_image, { "path", "load_flags" }, DEFVAL(LOAD_FLAG_CACHE_IMAGE));
+	OV_BIND_METHOD(AssetManager::get_texture, { "path", "load_flags" }, DEFVAL(LOAD_FLAG_CACHE_TEXTURE));
 	OV_BIND_METHOD(AssetManager::get_font, { "name" });
+
+	BIND_ENUM_CONSTANT(LOAD_FLAG_NONE);
+	BIND_ENUM_CONSTANT(LOAD_FLAG_CACHE_IMAGE);
+	BIND_ENUM_CONSTANT(LOAD_FLAG_CACHE_TEXTURE);
+	BIND_ENUM_CONSTANT(LOAD_FLAG_FLIP_Y);
 }
 
 AssetManager* AssetManager::get_singleton() {
@@ -32,55 +37,95 @@ AssetManager::~AssetManager() {
 	_singleton = nullptr;
 }
 
-Ref<Image> AssetManager::_load_image(StringName const& path) {
+Ref<Image> AssetManager::_load_image(StringName const& path, bool flip_y) {
 	GameSingleton* game_singleton = GameSingleton::get_singleton();
 	ERR_FAIL_NULL_V(game_singleton, nullptr);
+
 	const String lookedup_path =
 		std_to_godot_string(game_singleton->get_dataloader().lookup_image_file(godot_to_std_string(path)).string());
 	ERR_FAIL_COND_V_MSG(lookedup_path.is_empty(), nullptr, vformat("Failed to look up image: %s", path));
+
 	const Ref<Image> image = Utilities::load_godot_image(lookedup_path);
 	ERR_FAIL_COND_V_MSG(
-		image.is_null() || image->is_empty(), nullptr, vformat("Failed to load image: %s (looked up: %s)", path, lookedup_path)
+		image.is_null() || image->is_empty(), nullptr,
+		vformat("Failed to load image: %s (looked up: %s)", path, lookedup_path)
 	);
-	return image;
-}
 
-AssetManager::image_asset_t* AssetManager::_get_image_asset(StringName const& path, bool flip_y) {
-	image_asset_map_t::iterator it = image_assets.find(path);
-	if (it != image_assets.end()) {
-		return &it.value();
-	}
-	const Ref<Image> image = _load_image(path);
-	ERR_FAIL_NULL_V(image, nullptr);
 	if (flip_y) {
 		image->flip_y();
 	}
-	return &image_assets.emplace(std::move(path), AssetManager::image_asset_t { image, nullptr }).first.value();
+
+	return image;
 }
 
-Ref<Image> AssetManager::get_image(StringName const& path, bool cache, bool flip_y) {
-	if (cache) {
-		image_asset_t const* asset = _get_image_asset(path, flip_y);
-		ERR_FAIL_NULL_V(asset, nullptr);
-		return asset->image;
+Ref<Image> AssetManager::get_image(StringName const& path, LoadFlags load_flags) {
+	/* Check for an existing image entry indicating a previous load attempt, whether successful or not. */
+	const image_asset_map_t::iterator it = image_assets.find(path);
+	if (it != image_assets.end()) {
+		std::optional<Ref<Image>> const& cached_image = it->second.image;
+
+		if (cached_image.has_value()) {
+			ERR_FAIL_NULL_V_MSG(*cached_image, nullptr, vformat("Failed to load image previously: %s", path));
+
+			return *cached_image;
+		}
+	}
+
+	/* No load attempt has been made yet, so we try now. */
+	const Ref<Image> image = _load_image(path, load_flags & LOAD_FLAG_FLIP_Y);
+
+	if (image.is_valid()) {
+		if (load_flags & LOAD_FLAG_CACHE_IMAGE) {
+			image_assets[path].image = image;
+		}
+
+		return image;
 	} else {
-		return _load_image(path);
+		/* Mark both image and texture as failures, regardless of cache flags, in case of future load/creation attempts. */
+		image_assets[path] = { nullptr, nullptr };
+
+		ERR_FAIL_V_MSG(nullptr, vformat("Failed to load image: %s", path));
 	}
 }
 
-Ref<ImageTexture> AssetManager::get_texture(StringName const& path, bool flip_y) {
-	image_asset_t* asset = _get_image_asset(path, flip_y);
-	ERR_FAIL_NULL_V(asset, nullptr);
-	if (asset->texture.is_null()) {
-		asset->texture = ImageTexture::create_from_image(asset->image);
-		ERR_FAIL_NULL_V_MSG(asset->texture, nullptr, vformat("Failed to turn image into texture: %s", path));
+Ref<ImageTexture> AssetManager::get_texture(StringName const& path, LoadFlags load_flags) {
+	/* Check for an existing texture entry indicating a previous creation attempt, whether successful or not. */
+	const image_asset_map_t::const_iterator it = image_assets.find(path);
+	if (it != image_assets.end()) {
+		std::optional<Ref<ImageTexture>> const& cached_texture = it->second.texture;
+
+		if (cached_texture.has_value()) {
+			ERR_FAIL_NULL_V_MSG(*cached_texture, nullptr, vformat("Failed to create texture previously: %s", path));
+
+			return *cached_texture;
+		}
+	}
+
+	/* No creation attempt has yet been made, so we try now starting by finding the corresponding image. */
+	const Ref<Image> image = get_image(path, load_flags);
+	ERR_FAIL_NULL_V_MSG(image, nullptr, vformat("Failed to load image for texture: %s", path));
+
+	const Ref<ImageTexture> texture = ImageTexture::create_from_image(image);
+
+	if (texture.is_valid()) {
+		if (load_flags & LOAD_FLAG_CACHE_TEXTURE) {
+			image_assets[path].texture = texture;
+		}
+
+		return texture;
+	} else {
+		/* Mark texture as a failure, regardless of cache flags, in case of future creation attempts. */
+		image_assets[path].texture = nullptr;
+
+		ERR_FAIL_V_MSG(nullptr, vformat("Failed to create texture: %s", path));
 	}
-	return asset->texture;
 }
 
 Ref<Font> AssetManager::get_font(StringName const& name) {
 	const font_map_t::const_iterator it = fonts.find(name);
 	if (it != fonts.end()) {
+		ERR_FAIL_NULL_V_MSG(it->second, nullptr, vformat("Failed to load font previously: %s", name));
+
 		return it->second;
 	}
 
@@ -89,18 +134,35 @@ Ref<Font> AssetManager::get_font(StringName const& name) {
 	static const String image_ext = ".tga";
 
 	const StringName image_path = font_dir + name + image_ext;
-	const Ref<Image> image = get_image(image_path);
-	ERR_FAIL_NULL_V_MSG(image, nullptr, vformat("Failed to load font image %s for the font named %s", image_path, name));
+	const Ref<Image> image = get_image(image_path, LOAD_FLAG_NONE);
+	if (image.is_null()) {
+		fonts.emplace(name, nullptr);
+
+		ERR_FAIL_V_MSG(nullptr, vformat("Failed to load font image %s for the font named %s", image_path, name));
+	}
+
 	GameSingleton* game_singleton = GameSingleton::get_singleton();
 	ERR_FAIL_NULL_V(game_singleton, nullptr);
+
 	const String font_path = font_dir + name + font_ext;
 	const String lookedup_font_path =
 		std_to_godot_string(game_singleton->get_dataloader().lookup_file(godot_to_std_string(font_path)).string());
+	if (lookedup_font_path.is_empty()) {
+		fonts.emplace(name, nullptr);
+
+		ERR_FAIL_V_MSG(nullptr, vformat("Failed to look up font: %s", font_path));
+	}
+
 	const Ref<Font> font = Utilities::load_godot_font(lookedup_font_path, image);
-	ERR_FAIL_NULL_V_MSG(
-		font, nullptr,
-		vformat("Failed to load font file %s (looked up: %s) for the font named %s", font_path, lookedup_font_path, name)
-	);
-	fonts.emplace(std::move(name), font);
+	if (font.is_null()) {
+		fonts.emplace(name, nullptr);
+
+		ERR_FAIL_V_MSG(
+			nullptr,
+			vformat("Failed to load font file %s (looked up: %s) for the font named %s", font_path, lookedup_font_path, name)
+		);
+	}
+
+	fonts.emplace(name, font);
 	return font;
 }
diff --git a/extension/src/openvic-extension/singletons/AssetManager.hpp b/extension/src/openvic-extension/singletons/AssetManager.hpp
index c718d2a..0856d05 100644
--- a/extension/src/openvic-extension/singletons/AssetManager.hpp
+++ b/extension/src/openvic-extension/singletons/AssetManager.hpp
@@ -13,9 +13,22 @@ namespace OpenVic {
 
 		static inline AssetManager* _singleton = nullptr;
 
+	public:
+		enum LoadFlags {
+			LOAD_FLAG_NONE          = 0,
+			LOAD_FLAG_CACHE_IMAGE   = 1 << 0,
+			LOAD_FLAG_CACHE_TEXTURE = 1 << 1,
+			LOAD_FLAG_FLIP_Y        = 1 << 2
+		};
+
+		constexpr friend LoadFlags operator|(LoadFlags lhs, LoadFlags rhs) {
+			return static_cast<LoadFlags>(static_cast<int>(lhs) | static_cast<int>(rhs));
+		}
+
+	private:
 		struct image_asset_t {
-			godot::Ref<godot::Image> image;
-			godot::Ref<godot::ImageTexture> texture;
+			std::optional<godot::Ref<godot::Image>> image;
+			std::optional<godot::Ref<godot::ImageTexture>> texture;
 		};
 		/* deque_ordered_map to avoid the need to reallocate. */
 		using image_asset_map_t = deque_ordered_map<godot::StringName, image_asset_t>;
@@ -24,8 +37,7 @@ namespace OpenVic {
 		image_asset_map_t image_assets;
 		font_map_t fonts;
 
-		static godot::Ref<godot::Image> _load_image(godot::StringName const& path);
-		image_asset_t* _get_image_asset(godot::StringName const& path, bool flip_y);
+		static godot::Ref<godot::Image> _load_image(godot::StringName const& path, bool flip_y);
 
 	protected:
 		static void _bind_methods();
@@ -37,16 +49,27 @@ namespace OpenVic {
 		~AssetManager();
 
 		/* Search for and load an image at the specified path relative to the game defines, first checking the AssetManager's
-		 * image cache (if cache is true) in case it has already been loaded, and returning nullptr if image loading fails. */
-		godot::Ref<godot::Image> get_image(godot::StringName const& path, bool cache = true, bool flip_y = false);
+		 * image cache in case it has already been loaded, and returning nullptr if image loading fails. If the cache image
+		 * load flag is set then the loaded image will be stored in the AssetManager's image cache for future access; if the
+		 * flip y load flag is set then the image will be flipped vertically before being returned (if the image is already
+		 * in the cache then no flipping will occur, regardless of whether it was orginally flipped or not). */
+		godot::Ref<godot::Image> get_image(godot::StringName const& path, LoadFlags load_flags = LOAD_FLAG_CACHE_IMAGE);
 
-		/* Create a texture from an image found at the specified path relative to the game defines, fist checking
-		 * AssetManager's texture cache in case it has already been loaded, and returning nullptr if image loading
-		 * or texture creation fails. */
-		godot::Ref<godot::ImageTexture> get_texture(godot::StringName const& path, bool flip_y = false);
+		/* Create a texture from an image found at the specified path relative to the game defines, fist checking the
+		 * AssetManager's texture cache in case it has already been loaded, and returning nullptr if image loading or texture
+		 * creation fails. If the cache image load flag is set then the loaded image will be stored in the AssetManager's
+		 * image cache for future access; if the cache texture load flag is set then the created texture will be stored in the
+		 * AssetManager's texture cache for future access; if the flip y load flag is set then the image will be flipped
+		 * vertically before being used to create the texture (if the image is already in the cache then no flipping will
+		 * occur, regardless of whether it was orginally flipped or not). */
+		godot::Ref<godot::ImageTexture> get_texture(
+			godot::StringName const& path, LoadFlags load_flags = LOAD_FLAG_CACHE_TEXTURE
+		);
 
 		/* Search for and load a font with the specified name from the game defines' font directory, first checking the
 		 * AssetManager's font cache in case it has already been loaded, and returning nullptr if font loading fails. */
 		godot::Ref<godot::Font> get_font(godot::StringName const& name);
 	};
 }
+
+VARIANT_ENUM_CAST(OpenVic::AssetManager::LoadFlags);
diff --git a/extension/src/openvic-extension/singletons/GameSingleton.cpp b/extension/src/openvic-extension/singletons/GameSingleton.cpp
index df0e9a0..b8aef4f 100644
--- a/extension/src/openvic-extension/singletons/GameSingleton.cpp
+++ b/extension/src/openvic-extension/singletons/GameSingleton.cpp
@@ -339,7 +339,7 @@ Error GameSingleton::_load_terrain_variants() {
 	AssetManager* asset_manager = AssetManager::get_singleton();
 	ERR_FAIL_NULL_V(asset_manager, FAILED);
 	// Load the terrain texture sheet and prepare to slice it up
-	Ref<Image> terrain_sheet = asset_manager->get_image(terrain_texturesheet_path);
+	Ref<Image> terrain_sheet = asset_manager->get_image(terrain_texturesheet_path, AssetManager::LOAD_FLAG_NONE);
 	ERR_FAIL_NULL_V_MSG(terrain_sheet, FAILED, vformat("Failed to load terrain texture sheet: %s", terrain_texturesheet_path));
 
 	static constexpr int32_t SHEET_DIMS = 8, SHEET_SIZE = SHEET_DIMS * SHEET_DIMS;