Knob.hpp

//
// TGUI - Texus' Graphical User Interface
// Copyright (C) 2012-2026 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_KNOB_HPP
#define TGUI_KNOB_HPP
 
#include <TGUI/Renderers/KnobRenderer.hpp>
#include <TGUI/Widget.hpp>

 
namespace tgui
{
    class TGUI_API Knob : public Widget
    {
    public:
        using Ptr = std::shared_ptr<Knob>;            
        using ConstPtr = std::shared_ptr<const Knob>; 
 
        static constexpr char StaticWidgetType[] = "Knob"; 

        explicit Knob(const char* typeName = StaticWidgetType, bool initRenderer = true);

        [[nodiscard]] static Knob::Ptr create();

        [[nodiscard]] static Knob::Ptr copy(const Knob::ConstPtr& knob);

        [[nodiscard]] KnobRenderer* getSharedRenderer() override;
        [[nodiscard]] const KnobRenderer* getSharedRenderer() const override;

        [[nodiscard]] KnobRenderer* getRenderer() override;

        void setSize(const Layout2d& size) override;
        using Widget::setSize;

        void setStartRotation(float startRotation);

        [[nodiscard]] float getStartRotation() const;

        void setEndRotation(float endRotation);

        [[nodiscard]] float getEndRotation() const;

        void setMinimum(float minimum);

        [[nodiscard]] float getMinimum() const;

        void setMaximum(float maximum);

        [[nodiscard]] float getMaximum() const;

        void setValue(float value);

        [[nodiscard]] float getValue() const;

        void setClockwiseTurning(bool clockwise);

        [[nodiscard]] bool getClockwiseTurning() const;

        [[nodiscard]] bool isMouseOnWidget(Vector2f pos) const override;

        bool leftMousePressed(Vector2f pos) override;

        void mouseMoved(Vector2f pos) override;

        void draw(BackendRenderTarget& target, RenderStates states) const override;

 
    protected:
        [[nodiscard]] Signal& getSignal(String signalName) override;

        void rendererChanged(const String& property) override;

        [[nodiscard]] std::unique_ptr<DataIO::Node> save(SavingRenderersMap& renderers) const override;

        void load(const std::unique_ptr<DataIO::Node>& node, const LoadingRenderersMap& renderers) override;

        // Returns the size without the borders
        [[nodiscard]] Vector2f getInnerSize() const;

        // Recalculates the rotation of the knob.
        void recalculateRotation();

        // Makes a copy of the widget
        [[nodiscard]] Widget::Ptr clone() const override;

 
    public:
        SignalFloat onValueChange = {"ValueChanged"}; 

 
    protected:
        bool m_clockwiseTurning = true; // Does rotating clockwise increment the value?
        float m_startRotation = 270;
        float m_endRotation = 270;
 
        float m_minimum = 0;
        float m_value = 0;
        float m_maximum = 360;
 
        float m_angle = 270;
 
        Sprite m_spriteBackground;
        Sprite m_spriteForeground;
 
        // Cached renderer properties
        Borders m_bordersCached;
        Color m_borderColorCached;
        Color m_backgroundColorCached;
        Color m_thumbColorCached;
        float m_imageRotationCached = 0;
    };
} // namespace tgui
 
#endif // TGUI_KNOB_HPP