BackendGui.hpp

 
//
// TGUI - Texus' Graphical User Interface
// Copyright (C) 2012-2023 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_GUI_HPP
#define TGUI_BACKEND_GUI_HPP
 
#include <TGUI/Container.hpp>
#include <TGUI/RelFloatRect.hpp>
#include <TGUI/Event.hpp>
#include <TGUI/Cursor.hpp>
#include <TGUI/TwoFingerScrollDetect.hpp>
 
#if !TGUI_EXPERIMENTAL_USE_STD_MODULE
 #include <chrono>
 #include <stack>
#endif
 
 
TGUI_MODULE_EXPORT namespace tgui
{
 class TGUI_API BackendGui
 {
 public:
 
 BackendGui();
 
 // Deleted copy constructor
 BackendGui(const BackendGui& copy) = delete;
 
 // Deleted assignment operator overload
 BackendGui& operator=(const BackendGui& right) = delete;
 
 // Virtual destructor
 virtual ~BackendGui();
 
 
 void setAbsoluteViewport(const FloatRect& viewport);
 
 
 void setRelativeViewport(const FloatRect& viewport);
 
 
 TGUI_NODISCARD RelFloatRect getViewport() const;
 
 
 void setAbsoluteView(const FloatRect& view);
 
 
 void setRelativeView(const FloatRect& view);
 
 
 TGUI_NODISCARD RelFloatRect getView() const;
 
 
 bool handleEvent(Event event);
 
 
 void setTabKeyUsageEnabled(bool enabled);
 
 
 TGUI_NODISCARD bool isTabKeyUsageEnabled() const;
 
 
 virtual void draw();
 
 
 TGUI_NODISCARD RootContainer::Ptr getContainer() const;
 
 
 TGUI_NODISCARD std::shared_ptr<BackendRenderTarget> getBackendRenderTarget() const;
 
 
 void setFont(const Font& font);
 
 
 TGUI_NODISCARD Font getFont() const;
 
 
 TGUI_NODISCARD const std::vector<Widget::Ptr>& getWidgets() const;
 
 
 void add(const Widget::Ptr& widgetPtr, const String& widgetName = "");
 
 
 TGUI_NODISCARD Widget::Ptr get(const String& widgetName) const;
 
 
 template <class WidgetType>
 TGUI_NODISCARD typename WidgetType::Ptr get(const String& widgetName) const
 {
 return m_container->get<WidgetType>(widgetName);
 }
 
 
 bool remove(const Widget::Ptr& widget);
 
 
 void removeAllWidgets();
 
 
 TGUI_NODISCARD Widget::Ptr getFocusedChild() const;
 
 
 TGUI_NODISCARD Widget::Ptr getFocusedLeaf() const;
 
 
 TGUI_NODISCARD Widget::Ptr getWidgetAtPosition(Vector2f pos) const;
 
 
 TGUI_NODISCARD Widget::Ptr getWidgetBelowMouseCursor(Vector2i mousePos) const;
 
 
 bool focusNextWidget(bool recursive = true);
 
 
 bool focusPreviousWidget(bool recursive = true);
 
 
 void unfocusAllWidgets();
 
 
 void moveWidgetToFront(const Widget::Ptr& widget);
 
 
 void moveWidgetToBack(const Widget::Ptr& widget);
 
 
 std::size_t moveWidgetForward(const Widget::Ptr& widget);
 
 
 std::size_t moveWidgetBackward(const Widget::Ptr& widget);
 
 
 bool setWidgetIndex(const Widget::Ptr& widget, std::size_t index);
 
 
 TGUI_NODISCARD int getWidgetIndex(const Widget::Ptr& widget) const;
 
 
 void setOpacity(float opacity);
 
 
 TGUI_NODISCARD float getOpacity() const;
 
 
 void setTextSize(unsigned int size);
 
 
 TGUI_NODISCARD unsigned int getTextSize() const;
 
 
 void loadWidgetsFromFile(const String& filename, bool replaceExisting = true);
 
 
 void saveWidgetsToFile(const String& filename);
 
 
 void loadWidgetsFromStream(std::stringstream& stream, bool replaceExisting = true);
 
 
 void loadWidgetsFromStream(std::stringstream&& stream, bool replaceExisting = true);
 
 
 void saveWidgetsToStream(std::stringstream& stream) const;
 
 
 void setOverrideMouseCursor(Cursor::Type type);
 
 
 void restoreOverrideMouseCursor();
 
 
 void requestMouseCursor(Cursor::Type type);
 
 
 void setDrawingUpdatesTime(bool drawUpdatesTime);
 
 
 bool updateTime();
 
 
 bool updateTime(Duration elapsedTime);
 
 
 TGUI_NODISCARD Vector2f mapPixelToCoords(Vector2i pixel) const;
 
 
 TGUI_NODISCARD Vector2f mapCoordsToPixel(Vector2f coord) const;
 
 
 virtual void mainLoop(Color clearColor = {240, 240, 240}) = 0;
 
 
 virtual void startTextInput(FloatRect inputRect);
 
 
 virtual void stopTextInput();
 
 
 virtual void updateTextCursorPosition(FloatRect inputRect, Vector2f caretPos);
 
 
 protected:
 
 // Handles the backend-independent part of the two finger scrolling.
 // Returns whether the touch event should be absorbed by the gui.
 bool handleTwoFingerScroll(bool wasAlreadyScrolling);
 
 // Updates the view and changes the size of the root container when needed.
 // Derived classes should update m_framebufferSize in this function and then call this function from the base class.
 virtual void updateContainerSize();
 
 
 public:
 
 SignalFloatRect onViewChange = {"ViewChanged"}; 
 
 
 protected:
 
 std::chrono::steady_clock::time_point m_lastUpdateTime;
 bool m_windowFocused = true;
 
 RootContainer::Ptr m_container = std::make_shared<RootContainer>();
 
 Widget::Ptr m_visibleToolTip = nullptr;
 Duration m_tooltipTime;
 bool m_tooltipPossible = false;
 Vector2f m_toolTipRelativePos;
 Vector2i m_lastMousePos;
 TwoFingerScrollDetect m_twoFingerScroll;
 
 Vector2i m_framebufferSize;
 RelFloatRect m_viewport{RelativeValue{0}, RelativeValue{0}, RelativeValue{1}, RelativeValue{1}};
 RelFloatRect m_view{RelativeValue{0}, RelativeValue{0}, RelativeValue{1}, RelativeValue{1}};
 FloatRect m_lastView;
 
 bool m_drawUpdatesTime = true;
 bool m_tabKeyUsageEnabled = true;
 
 Cursor::Type m_requestedMouseCursor = Cursor::Type::Arrow;
 std::stack<Cursor::Type> m_overrideMouseCursors;
 
 std::shared_ptr<BackendRenderTarget> m_backendRenderTarget = nullptr;
 };
 
}
 
 
#endif // TGUI_BACKEND_GUI_HPP