VideoCommon: add a pixel shader asset

Source/Core/VideoCommon/Assets/ShaderAsset.h

@@ -0,0 +1,47 @@
+// Copyright 2023 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <map>
+#include <string>
+
+#include <picojson.h>
+
+#include "VideoCommon/Assets/CustomAsset.h"
+
+namespace VideoCommon
+{
+struct ShaderProperty
+{
+  enum class Type
+  {
+    Type_Undefined,
+    Type_Sampler2D,
+    Type_Max = Type_Sampler2D
+  };
+  Type m_type;
+  std::string m_description;
+};
+struct PixelShaderData
+{
+  static bool FromJson(const CustomAssetLibrary::AssetID& asset_id, const picojson::object& json,
+                       PixelShaderData* data);
+
+  // These shader properties describe the input that the
+  // shader expects to expose.  The key is text
+  // expected to be in the shader code and the propery
+  // describes various details about the input
+  std::map<std::string, ShaderProperty> m_properties;
+  std::string m_shader_source;
+};
+
+class PixelShaderAsset final : public CustomLoadableAsset<PixelShaderData>
+{
+public:
+  using CustomLoadableAsset::CustomLoadableAsset;
+
+private:
+  CustomAssetLibrary::LoadInfo LoadImpl(const CustomAssetLibrary::AssetID& asset_id) override;
+};
+}  // namespace VideoCommon