Qt 5.6 | Qt GUI | C++ Classes | TouchPoint

Qt 5.6.2 Reference Documentation

# TouchPoint Class

(QTouchEvent::TouchPoint)

The TouchPoint class provides information about a touch point in a QTouchEvent. More...

Header: | #include <TouchPoint>
qmake: | QT += gui
Since: | Qt 4.6

- List of all members, including inherited members

## Public Types

enum | InfoFlag { Pen }
flags | InfoFlags

## Public Functions

| TouchPoint(TouchPoint &&other)
InfoFlags | flags() const
int | id() const
QPointF | lastNormalizedPos() const
QPointF | lastPos() const
QPointF | lastScenePos() const
QPointF | lastScreenPos() const
QPointF | normalizedPos() const
QPointF | pos() const
qreal | pressure() const
QVector<QPointF> | rawScreenPositions() const
QRectF | rect() const
QPointF | scenePos() const
QRectF | sceneRect() const
QPointF | screenPos() const
QRectF | screenRect() const
QPointF | startNormalizedPos() const
QPointF | startPos() const
QPointF | startScenePos() const
QPointF | startScreenPos() const
Qt::TouchPointState | state() const
QVector2D | velocity() const

## Detailed Description

The TouchPoint class provides information about a touch point in a QTouchEvent.

## Member Type Documentation

### enum TouchPoint::InfoFlag
flags TouchPoint::InfoFlags

The values of this enum describe additional information about a touch point.

Constant | Value | Description
--- | --- | ---
`QTouchEvent::TouchPoint::Pen` | `0x0001` | Indicates that the contact has been made by a designated pointing device (e.g. a pen) instead of a finger.

The InfoFlags type is a typedef for QFlags<InfoFlag>. It stores an OR combination of InfoFlag values.

## Member Function Documentation

### TouchPoint::TouchPoint(TouchPoint &&other)

Move-constructs a TouchPoint instance, making it point to the same object that other was pointing to.

### InfoFlags TouchPoint::flags() const

Returns additional information about the touch point.

See also QTouchEvent::TouchPoint::InfoFlags.

### int TouchPoint::id() const

Returns the id number of this touch point.

Do not assume that id numbers start at zero or that they are sequential. Such an assumption is often false due to the way the underlying drivers work.

### QPointF TouchPoint::lastNormalizedPos() const

Returns the normalized position of this touch point from the previous touch event.

The coordinates are normalized to the size of the touch device, i.e. (0,0) is the top-left corner and (1,1) is the bottom-right corner.

See also normalizedPos() and startNormalizedPos().

### QPointF TouchPoint::lastPos() const

Returns the position of this touch point from the previous touch event, relative to the widget or QGraphicsItem that received the event.

See also pos() and startPos().

### QPointF TouchPoint::lastScenePos() const

Returns the scene position of this touch point from the previous touch event.

The scene position is the position in QGraphicsScene coordinates if the QTouchEvent is handled by a QGraphicsItem::touchEvent() reimplementation, and identical to the screen position for widgets.

See also scenePos() and startScenePos().

### QPointF TouchPoint::lastScreenPos() const

Returns the screen position of this touch point from the previous touch event.

See also screenPos() and startScreenPos().

### QPointF TouchPoint::normalizedPos() const

Returns the normalized position of this touch point.

The coordinates are normalized to the size of the touch device, i.e. (0,0) is the top-left corner and (1,1) is the bottom-right corner.

See also startNormalizedPos(), lastNormalizedPos(), and pos().

### QPointF TouchPoint::pos() const

Returns the position of this touch point, relative to the widget or QGraphicsItem that received the event.

See also startPos(), lastPos(), screenPos(), scenePos(), and normalizedPos().

### qreal TouchPoint::pressure() const

Returns the pressure of this touch point. The return value is in the range 0.0 to 1.0.

### QVector<QPointF> TouchPoint::rawScreenPositions() const

Returns the raw, unfiltered positions for the touch point. The positions are in native screen coordinates. To get local coordinates you can use mapFromGlobal() of the QWindow returned by QTouchEvent::window().

Note: Returns an empty vector if the touch device's capabilities do not include QTouchDevice::RawPositions.

Note: Native screen coordinates refer to the native orientation of the screen which, in case of mobile devices, is typically portrait. This means that on systems capable of screen orientation changes the positions in this list will not reflect the current orientation (unlike pos(), screenPos(), etc.) and will always be reported in the native orientation.

This function was introduced in Qt 5.0.

See also QTouchDevice::capabilities(), device(), and window().

### QRectF TouchPoint::rect() const

Returns the rect for this touch point, relative to the widget or QGraphicsItem that received the event. The rect is centered around the point returned by pos().

Note: This function returns an empty rect if the device does not report touch point sizes.

### QPointF TouchPoint::scenePos() const

Returns the scene position of this touch point.

The scene position is the position in QGraphicsScene coordinates if the QTouchEvent is handled by a QGraphicsItem::touchEvent() reimplementation, and identical to the screen position for widgets.

See also startScenePos(), lastScenePos(), and pos().

### QRectF TouchPoint::sceneRect() const

Returns the rect for this touch point in scene coordinates.

Note: This function returns an empty rect if the device does not report touch point sizes.

See also scenePos() and rect().

### QPointF TouchPoint::screenPos() const

Returns the screen position of this touch point.

See also startScreenPos(), lastScreenPos(), and pos().

### QRectF TouchPoint::screenRect() const

Returns the rect for this touch point in screen coordinates.

Note: This function returns an empty rect if the device does not report touch point sizes.

See also screenPos() and rect().

### QPointF TouchPoint::startNormalizedPos() const

Returns the normalized starting position of this touch point.

The coordinates are normalized to the size of the touch device, i.e. (0,0) is the top-left corner and (1,1) is the bottom-right corner.

See also normalizedPos() and lastNormalizedPos().

### QPointF TouchPoint::startPos() const

Returns the starting position of this touch point, relative to the widget or QGraphicsItem that received the event.

See also pos() and lastPos().

### QPointF TouchPoint::startScenePos() const

Returns the starting scene position of this touch point.

The scene position is the position in QGraphicsScene coordinates if the QTouchEvent is handled by a QGraphicsItem::touchEvent() reimplementation, and identical to the screen position for widgets.

See also scenePos() and lastScenePos().

### QPointF TouchPoint::startScreenPos() const

Returns the starting screen position of this touch point.

See also screenPos() and lastScreenPos().

### Qt::TouchPointState TouchPoint::state() const

Returns the current state of this touch point.

### QVector2D TouchPoint::velocity() const

Returns a velocity vector for this touch point. The vector is in the screen's coordinate system, using pixels per seconds for the magnitude.

Note: The returned vector is only valid if the touch device's capabilities include QTouchDevice::Velocity.

See also QTouchDevice::capabilities() and device().