File indexing completed on 2024-05-12 04:44:29

 // SPDX-FileCopyrightText: Lukas Sommer <sommerluk@gmail.com>
 // SPDX-License-Identifier: BSD-2-Clause OR MIT
 
 #ifndef ABSTRACTDIAGRAM_H
 #define ABSTRACTDIAGRAM_H
 
 #include "constpropagatinguniquepointer.h"
 #include "importexport.h"
 #include <qcolor.h>
 #include <qglobal.h>
 #include <qimage.h>
 #include <qsize.h>
 #include <qwidget.h>
 class QHideEvent;
 class QShowEvent;
 
 #if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
 #include <qtmetamacros.h>
 #else
 #include <qobjectdefs.h>
 #include <qstring.h>
 class QObject;
 #endif
 
 namespace PerceptualColor
 {
 class AbstractDiagramPrivate;
 
 /** @brief Base class for LCH diagrams.
  *
  * Provides some elements that are common for all LCH diagrams in this
  * library.
  *
  * @internal
  *
  * @note Qt provides some possibilities to declare that a certain widget
  * has a fixed ration between width and height. You can reimplement
  * <tt>QWidget::hasHeightForWidth()</tt> (indicates that the widget’s preferred
  * height depends on its width) and <tt>QWidget::heightForWidth()</tt>
  * (returns the preferred height for this widget, given the width <tt>w</tt>).
  * However, Qt’s layout management makes only very limited use of this
  * information. It is ignored, when the surrounding window is resized by
  * grabbing the window border with the mouse. It is however considered when
  * the surrounding window is resized by grabbing a <tt>QSizeGrip</tt>
  * widget. This behavior is inconsistent and would be surprising for the
  * user. Furthermore, if the widget is yet touching the border of the
  * screen, then the policy cannot be honored anyway; but it causes
  * flickering. Another possibility is QSizePolicy::setHeightForWidth or
  * QSizePolicy::setWidthForHeight which seem both to be “only supported for
  * QGraphicsLayout’s subclasses”. Therefore, it’s better not to use at all
  * these features; that’s the only way to provide a consistent and good
  * user experience.
  *
  * @todo Circular diagrams should be right-aligned on RTL layouts.
  *
  * @todo Touchscreen support: Magnify the handle circle, when diagram is
  * used on a touch device?  */
 class PERCEPTUALCOLOR_IMPORTEXPORT AbstractDiagram : public QWidget
 {
     Q_OBJECT
 
 public:
     Q_INVOKABLE explicit AbstractDiagram(QWidget *parent = nullptr);
     /** @brief Default destructor */
     virtual ~AbstractDiagram() noexcept override;
 
 protected:
     virtual void actualVisibilityToggledEvent();
     void callUpdate();
     [[nodiscard]] QColor focusIndicatorColor() const;
     [[nodiscard]] int gradientMinimumLength() const;
     [[nodiscard]] int gradientThickness() const;
     virtual void hideEvent(QHideEvent *event) override;
     [[nodiscard]] bool isActuallyVisible() const;
     [[nodiscard]] int maximumPhysicalSquareSize() const;
     [[nodiscard]] qreal maximumWidgetSquareSize() const;
     [[nodiscard]] QSize physicalPixelSize() const;
     [[nodiscard]] QColor handleColorFromBackgroundLightness(qreal lightness) const;
     [[nodiscard]] int handleOutlineThickness() const;
     [[nodiscard]] qreal handleRadius() const;
     virtual void showEvent(QShowEvent *event) override;
     [[nodiscard]] int spaceForFocusIndicator() const;
     [[nodiscard]] QImage transparencyBackground() const;
 
 private:
     Q_DISABLE_COPY(AbstractDiagram)
 
     /** @internal
      *
      * @brief Declare the private implementation as friend class.
      *
      * This allows the private class to access the protected members and
      * functions of instances of <em>this</em> class. */
     friend class AbstractDiagramPrivate;
     /** @brief Pointer to implementation (pimpl) */
     ConstPropagatingUniquePointer<AbstractDiagramPrivate> d_pointer;
 
     /** @internal @brief Only for unit tests. */
     friend class TestAbstractDiagram;
 };
 
 } // namespace PerceptualColor
 
 #endif // ABSTRACTDIAGRAM_H