Backend.hpp

 
//
// TGUI - Texus' Graphical User Interface
// Copyright (C) 2012-2022 Bruno Van de Velde (vdv_b@tgui.eu)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
//    you must not claim that you wrote the original software.
//    If you use this software in a product, an acknowledgment
//    in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
//    and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
 
 
#ifndef TGUI_BACKEND_HPP
#define TGUI_BACKEND_HPP
 
#include <TGUI/Font.hpp>
#include <TGUI/Event.hpp>
#include <TGUI/Cursor.hpp>
#include <cstdint>
#include <memory>
 
 
namespace tgui
{
    class GuiBase;
    class BackendBase;
    class BackendFontBase;
    class BackendTextBase;
    class BackendTextureBase;
 
 
    TGUI_API bool isBackendSet();
 
 
    TGUI_API void setBackend(std::shared_ptr<BackendBase> backend);
 
 
    TGUI_API std::shared_ptr<BackendBase> getBackend();
 
 
 
    class TGUI_API BackendBase
    {
    public:
 
        BackendBase() = default;
 
 
        // The object cannot be copied
        BackendBase(const BackendBase&) = delete;
 
 
        // The object cannot be copied
        BackendBase& operator=(const BackendBase&) = delete;
 
 
        virtual ~BackendBase() = default;
 
 
        void setDestroyOnLastGuiDetatch(bool destroyOnDetatch);
 
 
        virtual void attachGui(GuiBase* gui) = 0;
 
 
        virtual void detatchGui(GuiBase* gui) = 0;
 
 
        virtual Font createDefaultFont() = 0;
 
 
        virtual std::shared_ptr<BackendFontBase> createFont() = 0;
 
 
        virtual std::shared_ptr<BackendTextBase> createText() = 0;
 
 
        virtual std::shared_ptr<BackendTextureBase> createTexture() = 0;
 
 
        virtual void setMouseCursorStyle(Cursor::Type type, const std::uint8_t* pixels, Vector2u size, Vector2u hotspot) = 0;
 
 
        virtual void resetMouseCursorStyle(Cursor::Type type) = 0;
 
 
        virtual void setMouseCursor(GuiBase* gui, Cursor::Type type) = 0;
 
 
        virtual void openVirtualKeyboard(const FloatRect& inputRect) = 0;
 
 
        virtual void closeVirtualKeyboard() = 0;
 
 
        virtual bool isKeyboardModifierPressed(Event::KeyModifier modifierKey) = 0;
 
 
        virtual void setClipboard(const String& contents);
 
 
        virtual String getClipboard() const;
 
 
        virtual std::unique_ptr<std::uint8_t[]> readFileFromAndroidAssets(const String& filename, std::size_t& fileSize) const;
 
 
    protected:
 
        bool m_destroyOnLastGuiDetatch = false;
        String m_clipboardContents;
    };
 
}
 
 
#endif // TGUI_BACKEND_HPP