SColorWheel.h

Go to the documentation of this file.

// Copyright Epic Games, Inc. All Rights Reserved.
 
#pragma once
 
#include "CoreMinimal.h"
#include "Misc/Attribute.h"
#include "Input/Reply.h"
#include "Widgets/DeclarativeSyntaxSupport.h"
#include "Widgets/SLeafWidget.h"
#include "Framework/SlateDelegates.h"
#include "Styling/CoreStyle.h"
 
class FPaintArgs;
class FSlateWindowElementList;
struct FSlateBrush;
 
class SColorWheel
    : public SLeafWidget
{
public:
 
    SLATE_BEGIN_ARGS(SColorWheel)
        : _SelectedColor()
        , _ColorWheelBrush(FCoreStyle::Get().GetBrush("ColorWheel.HueValueCircle"))
        , _OnMouseCaptureBegin()
        , _OnMouseCaptureEnd()
        , _OnValueChanged()
        , _CtrlMultiplier(0.1f)
    { }
    
        SLATE_ATTRIBUTE(FLinearColor, SelectedColor)
 
        
        SLATE_ATTRIBUTE(const FSlateBrush*, ColorWheelBrush)
        
        
        SLATE_EVENT(FSimpleDelegate, OnMouseCaptureBegin)
 
        
        SLATE_EVENT(FSimpleDelegate, OnMouseCaptureEnd)
 
        
        SLATE_EVENT(FOnLinearColorValueChanged, OnValueChanged)
 
        
        SLATE_ATTRIBUTE(float, CtrlMultiplier)
 
    SLATE_END_ARGS()
    
public:
    SLATE_API SColorWheel();
    SLATE_API virtual ~SColorWheel();
 
    SLATE_API void Construct(const FArguments& InArgs);
 
    void ShowSelector(bool bShow = true) { bShouldDrawSelector = bShow; }
 
public:
 
    //~ SWidget overrides
 
    SLATE_API virtual FVector2D ComputeDesiredSize(float) const override;
    SLATE_API virtual FReply OnMouseButtonDoubleClick(const FGeometry& InMyGeometry, const FPointerEvent& InMouseEvent) override;
    SLATE_API virtual FReply OnMouseButtonDown(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) override;
    SLATE_API virtual FReply OnMouseButtonUp(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) override;
    SLATE_API virtual FReply OnMouseMove(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) override;
    SLATE_API virtual int32 OnPaint(const FPaintArgs& Args, const FGeometry& AllottedGeometry, const FSlateRect& MyCullingRect, FSlateWindowElementList& OutDrawElements, int32 LayerId, const FWidgetStyle& InWidgetStyle, bool bParentEnabled) const override;
    SLATE_API virtual FCursorReply OnCursorQuery(const FGeometry& MyGeometry, const FPointerEvent& CursorEvent) const override;
 
protected:
 
    SLATE_API UE::Slate::FDeprecateVector2DResult CalcRelativePositionFromCenter() const;
 
    SLATE_API bool ProcessMouseAction(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent, bool bProcessWhenOutsideColorWheel);
 
private:
 
    const FSlateBrush* Image;
    
    TSlateAttribute<FLinearColor, EInvalidateWidgetReason::Paint> SelectedColor;
 
    TAttribute<float> CtrlMultiplier;
 
    const FSlateBrush* SelectorImage;
 
    bool bShouldDrawSelector;
 
    bool bDragging = false;
 
    FVector2f LastWheelPosition;
 
private:
 
    FSimpleDelegate OnMouseCaptureBegin;
 
    FSimpleDelegate OnMouseCaptureEnd;
 
    FOnLinearColorValueChanged OnValueChanged;
};