Improve error handling in AssetLoader

build/pomdog/CMakeLists.txt

@@ -16,6 +16,9 @@ source_group(Audio                        REGULAR_EXPRESSION "(include/Pomdog|sr
 source_group(Basic                        REGULAR_EXPRESSION "(include/Pomdog|src)/Basic/*")
 source_group(Content                      REGULAR_EXPRESSION "(include/Pomdog|src)/Content/*")
 source_group(Content\\AssetBuilders       REGULAR_EXPRESSION "(include/Pomdog|src)/Content/AssetBuilders/*")
+source_group(Content\\AssetLoaders        REGULAR_EXPRESSION "(include/Pomdog|src)/Content/AssetLoaders/*")
+source_group(Content\\Audio               REGULAR_EXPRESSION "(include/Pomdog|src)/Content/Audio/*")
+source_group(Content\\Image               REGULAR_EXPRESSION "(include/Pomdog|src)/Content/Image/*")
 source_group(Content\\Utility             REGULAR_EXPRESSION "(include/Pomdog|src)/Content/Utility/*")
 source_group(Graphics                     REGULAR_EXPRESSION "(include/Pomdog|src)/Graphics/*")
 source_group(Graphics\\ShaderCompilers    REGULAR_EXPRESSION "(include/Pomdog|src)/Graphics/ShaderCompilers/*")
@@ -85,13 +88,17 @@ set(POMDOG_SOURCES_CORE
   ${POMDOG_DIR}/include/Pomdog/Content/AssetBuilders/PipelineStateBuilder.hpp
   ${POMDOG_DIR}/include/Pomdog/Content/AssetBuilders/ShaderBuilder.hpp
   ${POMDOG_DIR}/include/Pomdog/Content/Utility/BinaryFileStream.hpp
+  ${POMDOG_DIR}/include/Pomdog/Content/Audio/WAV.hpp
+  ${POMDOG_DIR}/include/Pomdog/Content/Image/ImageBuffer.hpp
+  ${POMDOG_DIR}/include/Pomdog/Content/Image/DDS.hpp
+  ${POMDOG_DIR}/include/Pomdog/Content/Image/PNG.hpp
   ${POMDOG_DIR}/include/Pomdog/Content/Utility/BinaryReader.hpp
   ${POMDOG_DIR}/include/Pomdog/Content/Utility/MakeFourCC.hpp
   ${POMDOG_DIR}/include/Pomdog/Content/detail/AssetDictionary.hpp
   ${POMDOG_DIR}/include/Pomdog/Content/detail/AssetLoaderContext.hpp
-  ${POMDOG_DIR}/include/Pomdog/Content/detail/AssetLoader.hpp
-  ${POMDOG_DIR}/include/Pomdog/Content/detail/AssetLoaders/AudioClipLoader.hpp
-  ${POMDOG_DIR}/include/Pomdog/Content/detail/AssetLoaders/Texture2DLoader.hpp
+  ${POMDOG_DIR}/include/Pomdog/Content/AssetLoaders/AssetLoader.hpp
+  ${POMDOG_DIR}/include/Pomdog/Content/AssetLoaders/AudioClipLoader.hpp
+  ${POMDOG_DIR}/include/Pomdog/Content/AssetLoaders/Texture2DLoader.hpp
   ${POMDOG_DIR}/include/Pomdog/Graphics/Blend.hpp
   ${POMDOG_DIR}/include/Pomdog/Graphics/BlendDescription.hpp
   ${POMDOG_DIR}/include/Pomdog/Graphics/BlendOperation.hpp
@@ -255,12 +262,9 @@ set(POMDOG_SOURCES_CORE
   ${POMDOG_DIR}/src/Content/AssetBuilders/ShaderBuilder.cpp
   ${POMDOG_DIR}/src/Content/AssetLoaders/AudioClipLoader.cpp
   ${POMDOG_DIR}/src/Content/AssetLoaders/Texture2DLoader.cpp
-  ${POMDOG_DIR}/src/Content/Utility/DDSTextureReader.cpp
-  ${POMDOG_DIR}/src/Content/Utility/DDSTextureReader.hpp
-  ${POMDOG_DIR}/src/Content/Utility/MSWaveAudioLoader.cpp
-  ${POMDOG_DIR}/src/Content/Utility/MSWaveAudioLoader.hpp
-  ${POMDOG_DIR}/src/Content/Utility/PNGTextureReader.cpp
-  ${POMDOG_DIR}/src/Content/Utility/PNGTextureReader.hpp
+  ${POMDOG_DIR}/src/Content/Audio/WAV.cpp
+  ${POMDOG_DIR}/src/Content/Image/DDS.cpp
+  ${POMDOG_DIR}/src/Content/Image/PNG.cpp
   ${POMDOG_DIR}/src/Graphics/ConstantBuffer.cpp
   ${POMDOG_DIR}/src/Graphics/EffectBinaryParameter.cpp
   ${POMDOG_DIR}/src/Graphics/EffectReflection.cpp

include/Pomdog/Content/detail/AssetLoaders/AudioClipLoader.hpp → include/Pomdog/Content/AssetLoaders/AudioClipLoader.hpp

@@ -3,23 +3,23 @@
 #pragma once
 
 #include "Pomdog/Basic/Export.hpp"
-#include "Pomdog/Content/detail/AssetLoader.hpp"
+#include "Pomdog/Content/AssetLoaders/AssetLoader.hpp"
+#include "Pomdog/Utility/Errors.hpp"
 #include <memory>
 #include <string>
+#include <tuple>
 
 namespace Pomdog {
+class AssetManager;
 class AudioClip;
 } // namespace Pomdog
 
 namespace Pomdog::Detail {
 
-class AssetLoaderContext;
-
 template <>
 struct POMDOG_EXPORT AssetLoader<AudioClip> final {
-    std::shared_ptr<AudioClip> operator()(
-        const AssetLoaderContext& loaderContext,
-        const std::string& assetName);
+    [[nodiscard]] std::tuple<std::shared_ptr<AudioClip>, std::shared_ptr<Error>>
+    operator()(AssetManager& assets, const std::string& filePath);
 };
 
 } // namespace Pomdog::Detail

include/Pomdog/Content/detail/AssetLoaders/Texture2DLoader.hpp → include/Pomdog/Content/AssetLoaders/Texture2DLoader.hpp

@@ -3,23 +3,23 @@
 #pragma once
 
 #include "Pomdog/Basic/Export.hpp"
-#include "Pomdog/Content/detail/AssetLoader.hpp"
+#include "Pomdog/Content/AssetLoaders/AssetLoader.hpp"
+#include "Pomdog/Utility/Errors.hpp"
 #include <memory>
 #include <string>
+#include <tuple>
 
 namespace Pomdog {
+class AssetManager;
 class Texture2D;
 } // namespace Pomdog
 
 namespace Pomdog::Detail {
 
-class AssetLoaderContext;
-
 template <>
 struct POMDOG_EXPORT AssetLoader<Texture2D> final {
-    std::shared_ptr<Texture2D> operator()(
-        const AssetLoaderContext& loaderContext,
-        const std::string& assetName);
+    [[nodiscard]] std::tuple<std::shared_ptr<Texture2D>, std::shared_ptr<Error>>
+    operator()(AssetManager& assets, const std::string& filePath);
 };
 
 } // namespace Pomdog::Detail

include/Pomdog/Content/Audio/WAV.hpp

@@ -0,0 +1,21 @@
+// Copyright (c) 2013-2019 mogemimi. Distributed under the MIT license.
+
+#pragma once
+
+#include "Pomdog/Audio/detail/ForwardDeclarations.hpp"
+#include "Pomdog/Basic/Export.hpp"
+#include "Pomdog/Utility/Errors.hpp"
+#include <cstddef>
+#include <fstream>
+#include <memory>
+#include <tuple>
+#include <vector>
+
+namespace Pomdog::WAV {
+
+/// Reads an audio data from Waveform Audio File (.wav) format data.
+[[nodiscard]] POMDOG_EXPORT
+std::tuple<std::shared_ptr<AudioClip>, std::shared_ptr<Error>>
+Load(std::ifstream&& stream, std::size_t byteLength);
+
+} // namespace Pomdog::WAV

include/Pomdog/Content/Image/DDS.hpp

@@ -0,0 +1,20 @@
+// Copyright (c) 2013-2019 mogemimi. Distributed under the MIT license.
+
+#pragma once
+
+#include "Pomdog/Basic/Export.hpp"
+#include "Pomdog/Content/Image/ImageBuffer.hpp"
+#include "Pomdog/Utility/Errors.hpp"
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <tuple>
+
+namespace Pomdog::DDS {
+
+/// Reads a DDS image from data (.dds).
+[[nodiscard]] POMDOG_EXPORT
+std::tuple<ImageBuffer, std::shared_ptr<Error>>
+Decode(const std::uint8_t* data, std::size_t size);
+
+} // namespace Pomdog::DDS

include/Pomdog/Content/Image/ImageBuffer.hpp

@@ -0,0 +1,36 @@
+// Copyright (c) 2013-2019 mogemimi. Distributed under the MIT license.
+
+#pragma once
+
+#include "Pomdog/Basic/Export.hpp"
+#include "Pomdog/Graphics/SurfaceFormat.hpp"
+#include <cstdint>
+#include <memory>
+#include <vector>
+
+namespace Pomdog {
+
+struct POMDOG_EXPORT ImageBuffer final {
+    /// Raw pixel data.
+    std::vector<std::uint8_t> RawData;
+
+    /// Pointer to pixel data array.
+    const std::uint8_t* PixelData = nullptr;
+
+    /// Size of byte array of pixel data.
+    std::size_t ByteLength = 0;
+
+    /// Width of the image in pixels.
+    std::int32_t Width = 1;
+
+    /// Height of the image in pixels.
+    std::int32_t Height = 1;
+
+    /// The number of mipmap levels in a multilevel texture.
+    std::int32_t MipmapCount = 0;
+
+    /// Surface format of the image.
+    SurfaceFormat Format = SurfaceFormat::R8_UNorm;
+};
+
+} // namespace Pomdog

include/Pomdog/Content/Image/PNG.hpp

@@ -0,0 +1,20 @@
+// Copyright (c) 2013-2019 mogemimi. Distributed under the MIT license.
+
+#pragma once
+
+#include "Pomdog/Basic/Export.hpp"
+#include "Pomdog/Content/Image/ImageBuffer.hpp"
+#include "Pomdog/Utility/Errors.hpp"
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <tuple>
+
+namespace Pomdog::PNG {
+
+/// Reads a PNG image from data (.png).
+[[nodiscard]] POMDOG_EXPORT
+std::tuple<ImageBuffer, std::shared_ptr<Error>>
+Decode(const std::uint8_t* data, std::size_t size);
+
+} // namespace Pomdog::PNG

src/Content/AssetLoaders/AudioClipLoader.cpp

@@ -1,13 +1,14 @@
 // Copyright (c) 2013-2019 mogemimi. Distributed under the MIT license.
 
-#include "Pomdog/Content/detail/AssetLoaders/AudioClipLoader.hpp"
-#include "../Utility/MSWaveAudioLoader.hpp"
+#include "Pomdog/Content/AssetLoaders/AudioClipLoader.hpp"
 #include "Pomdog/Audio/AudioClip.hpp"
+#include "Pomdog/Content/Audio/WAV.hpp"
 #include "Pomdog/Content/Utility/BinaryReader.hpp"
 #include "Pomdog/Content/Utility/MakeFourCC.hpp"
-#include "Pomdog/Content/detail/AssetLoaderContext.hpp"
+#include "Pomdog/Content/AssetManager.hpp"
 #include "Pomdog/Utility/Assert.hpp"
 #include "Pomdog/Utility/Exception.hpp"
+#include "Pomdog/Utility/FileSystem.hpp"
 #include <fstream>
 #include <memory>
 #include <string>
@@ -16,37 +17,51 @@
 
 namespace Pomdog::Detail {
 
-std::shared_ptr<AudioClip> AssetLoader<AudioClip>::operator()(
-    const AssetLoaderContext& loaderContext, const std::string& assetName)
+std::tuple<std::shared_ptr<AudioClip>, std::shared_ptr<Error>>
+AssetLoader<AudioClip>::operator()([[maybe_unused]] AssetManager& assets, const std::string& filePath)
 {
-    auto binaryStream = loaderContext.OpenStream(assetName);
+    std::ifstream stream{filePath, std::ifstream::binary};
 
-    if (!binaryStream.Stream) {
-        POMDOG_THROW_EXCEPTION(std::runtime_error,
-            "Cannot open the wave file: " + assetName);
+    if (!stream) {
+        auto err = Errors::New("cannot open the file, " + filePath);
+        return std::make_tuple(nullptr, std::move(err));
     }
 
-    if (binaryStream.SizeInBytes < (sizeof(std::uint8_t) * 12)) {
-        POMDOG_THROW_EXCEPTION(std::runtime_error,
-            "The audio file is too small: " + assetName);
+    auto[byteLength, sizeErr] = FileSystem::GetFileSize(filePath);
+    if (sizeErr != nullptr) {
+        auto err = Errors::Wrap(std::move(sizeErr), "failed to get file size, " + filePath);
+        return std::make_tuple(nullptr, std::move(err));
     }
 
-    auto & stream = binaryStream.Stream;
+    POMDOG_ASSERT(stream);
+
+    if (byteLength < (sizeof(std::uint8_t) * 12)) {
+        auto err = Errors::New("The audio file is too small " + filePath);
+        return std::make_tuple(nullptr, std::move(err));
+    }
 
     auto signature = BinaryReader::ReadArray<std::uint8_t, 12>(stream);
     if (stream.fail()) {
-        POMDOG_THROW_EXCEPTION(std::runtime_error,
-            "Failed to read the audio file.");
+        auto err = Errors::New("failed to read signature in the file " + filePath);
+        return std::make_tuple(nullptr, std::move(err));
     }
 
+    stream.clear();
+    stream.seekg(0, std::ios_base::beg);
+
     const auto fourCC = MakeFourCC(signature[0], signature[1], signature[2], signature[3]);
 
     if (fourCC == MakeFourCC('R', 'I', 'F', 'F')) {
         const auto fccType = MakeFourCC(signature[8], signature[9], signature[10], signature[11]);
         if (fccType == MakeFourCC('W', 'A', 'V', 'E')) {
-            // This file format is RIFF waveform audio.
-            auto audioClip = MSWaveAudioLoader::Load(std::move(binaryStream));
-            return std::move(audioClip);
+            // NOTE: This file format is RIFF waveform audio.
+            auto[audioClip, loadErr] = WAV::Load(std::move(stream), byteLength);
+
+            if (loadErr != nullptr) {
+                auto err = Errors::Wrap(std::move(loadErr), "Cannot load the wave file " + filePath);
+                return std::make_tuple(nullptr, std::move(err));
+            }
+            return std::make_tuple(std::move(audioClip), nullptr);
         }
     }
     else if (fourCC == MakeFourCC('O', 'g', 'g', 'S')) {
@@ -55,7 +70,8 @@ std::shared_ptr<AudioClip> AssetLoader<AudioClip>::operator()(
             "Pomdog does not yet supported Ogg Vorbis format.");
     }
 
-    POMDOG_THROW_EXCEPTION(std::runtime_error, "Not implemented.");
+    auto err = Errors::New("This audio file format is not supported " + filePath);
+    return std::make_tuple(nullptr, std::move(err));
 }
 
 } // namespace Pomdog::Detail