Graphics: Add RenderSystem and frame pipeline

include/Nazara/Graphics/AbstractViewer.hpp

@@ -0,0 +1,32 @@
+// Copyright (C) 2020 Jérôme Leclercq
+// This file is part of the "Nazara Engine - Graphics module"
+// For conditions of distribution and use, see copyright notice in Config.hpp
+
+#pragma once
+
+#ifndef NAZARA_ABSTRACTVIEWER_HPP
+#define NAZARA_ABSTRACTVIEWER_HPP
+
+#include <Nazara/Prerequisites.hpp>
+#include <Nazara/Graphics/Config.hpp>
+
+namespace Nz
+{
+	class RenderTarget;
+	class ViewerInstance;
+
+	class NAZARA_GRAPHICS_API AbstractViewer
+	{
+		public:
+			AbstractViewer() = default;
+			~AbstractViewer() = default;
+
+			virtual const RenderTarget& GetRenderTarget() = 0;
+			virtual ViewerInstance& GetViewerInstance() = 0;
+			virtual const ViewerInstance& GetViewerInstance() const = 0;
+	};
+}
+
+#include <Nazara/Graphics/AbstractViewer.inl>
+
+#endif