KisCanvasNavigationActionStrategy Class Reference

#include <KisCanvasNavigationActionStrategy.h>

Inheritance diagram for KisCanvasNavigationActionStrategy:

Classes
struct	SnappedRotationData

Public Types
enum	Flag {   None = 0x0 , PanEnabled = 0x1 , ZoomEnabled = 0x2 , RotationEnabled = 0x4 ,   ZoomDescrete = 0x8 , RotationDescrete = 0x10 }

Public Member Functions
Flags	flags () const
virtual void	inputEvent (QEvent *event)=0
	KisCanvasNavigationActionStrategy (const Flags &flags)
virtual bool	supportsEvent (QEvent *event) const =0
virtual	~KisCanvasNavigationActionStrategy ()=default

Static Public Member Functions
static qreal	canvasRotationAngleContinuous (qreal currentRotationOffset, qreal currectCanvasRotation, SnappedRotationData &data)
static qreal	canvasRotationAngleDescrete (qreal currentRotationOffset, SnappedRotationData &data)

Private Attributes
Flags	m_flags {None}

Detailed Description

Definition at line 15 of file KisCanvasNavigationActionStrategy.h.

Member Enumeration Documentation

Flag

enum KisCanvasNavigationActionStrategy::Flag

Enumerator
None
PanEnabled
ZoomEnabled
RotationEnabled
ZoomDescrete
RotationDescrete

Definition at line 18 of file KisCanvasNavigationActionStrategy.h.

              {
        None = 0x0,
        PanEnabled = 0x1,
        ZoomEnabled = 0x2,
        RotationEnabled = 0x4,
        ZoomDescrete = 0x8,
        RotationDescrete = 0x10,
    };

Constructor & Destructor Documentation

KisCanvasNavigationActionStrategy()

KisCanvasNavigationActionStrategy::KisCanvasNavigationActionStrategy

(

const Flags &

flags

)

Definition at line 76 of file KisCanvasNavigationActionStrategy.cpp.

    : m_flags(flags)
{
}

~KisCanvasNavigationActionStrategy()

virtual KisCanvasNavigationActionStrategy::~KisCanvasNavigationActionStrategy ( )

virtualdefault

Member Function Documentation

canvasRotationAngleContinuous()

qreal KisCanvasNavigationActionStrategy::canvasRotationAngleContinuous ( qreal currentRotationOffset, qreal currectCanvasRotation, SnappedRotationData & data )

static

Definition at line 23 of file KisCanvasNavigationActionStrategy.cpp.

{
    if (!data.previousAngle) {
        data.previousAngle = currentRelativeRotation;
        return 0;
    }
    qreal rotationAngle = (180 / M_PI) * (currentRelativeRotation - data.previousAngle);
    data.previousAngle = currentRelativeRotation;
 
    const qreal canvasAnglePostRotation = currectCanvasRotation + rotationAngle;
    const qreal snapDelta = angleForSnapping(canvasAnglePostRotation);
    // we snap the canvas to an angle that is a multiple of 45
    if (abs(snapDelta) <= 2 && abs(data.accumRotationAngle) <= 2) {
        // accumulate the relative angle of finger from the point when we started snapping
        data.accumRotationAngle += rotationAngle;
        rotationAngle = rotationAngle - snapDelta;
    } else {
        // snap the canvas out using the accumulated angle
        rotationAngle += data.accumRotationAngle;
        data.accumRotationAngle = 0;
    }
 
    return rotationAngle;
}

References KisCanvasNavigationActionStrategy::SnappedRotationData::accumRotationAngle, M_PI, and KisCanvasNavigationActionStrategy::SnappedRotationData::previousAngle.

canvasRotationAngleDescrete()

qreal KisCanvasNavigationActionStrategy::canvasRotationAngleDescrete ( qreal currentRotationOffset, SnappedRotationData & data )

static

Definition at line 48 of file KisCanvasNavigationActionStrategy.cpp.

{
    if (!data.initialReferenceAngle) {
        data.initialReferenceAngle = currentRelativeRotation;
        return 0;
    }
    qreal rotationAngle = 0;
    const qreal relativeAngle = (180 / M_PI) * (currentRelativeRotation - data.initialReferenceAngle);
    const qreal rotationThreshold = 15;
 
    // if the canvas is moved in either direction with an angle greater than the threshold, we rotate the canvas in
    // that direction by 15°.
    if (std::abs(relativeAngle) >= rotationThreshold && std::abs(relativeAngle) <= (360 - rotationThreshold)) {
        // set reference as currentAngle to check if we go beyond the threshold next time
        data.initialReferenceAngle = currentRelativeRotation;
 
        if (std::abs(relativeAngle) <= 180) {
            rotationAngle = KisAlgebra2D::copysign(15.0, relativeAngle);
        } else {
            // if we're over 180, it means the canvas has to be rotated in the opposite direction of the current
            // angle. E.g if the relative angle is +341° then we move the canvas by -15° (because the actual effect
            // is 341 - 360 = -19°  on the original theta).
            rotationAngle = KisAlgebra2D::copysign(15.0, -relativeAngle);
        }
    }
    return rotationAngle;
}

References KisAlgebra2D::copysign(), KisCanvasNavigationActionStrategy::SnappedRotationData::initialReferenceAngle, and M_PI.

flags()

KisCanvasNavigationActionStrategy::Flags KisCanvasNavigationActionStrategy::flags

(

)

const

Definition at line 81 of file KisCanvasNavigationActionStrategy.cpp.

{
    return m_flags;
}

References m_flags.

inputEvent()

virtual void KisCanvasNavigationActionStrategy::inputEvent ( QEvent * event )

pure virtual

Implemented in KisCanvasNavigationActionStrategyNativeGesture, and KisCanvasNavigationActionStrategyTouch.

supportsEvent()

virtual bool KisCanvasNavigationActionStrategy::supportsEvent ( QEvent * event ) const

pure virtual

Implemented in KisCanvasNavigationActionStrategyNativeGesture, and KisCanvasNavigationActionStrategyTouch.

Member Data Documentation

m_flags

Flags KisCanvasNavigationActionStrategy::m_flags {None}

private

Definition at line 47 of file KisCanvasNavigationActionStrategy.h.

{None};

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The documentation for this class was generated from the following files:

• libs/ui/input/KisCanvasNavigationActionStrategy.h
• libs/ui/input/KisCanvasNavigationActionStrategy.cpp