- Qt 6.12
- Qt Canvas Painter
- C++ Classes
- QCanvasLinearGradient
- Qt Canvas Painter | Commercial or GPLv3

# QCanvasLinearGradient Class

QCanvasLinearGradient is a brush for linear gradient painting. More...

Header: | `#include <QCanvasLinearGradient>`
CMake: | `find_package(Qt6 REQUIRED COMPONENTS CanvasPainter)` `target_link_libraries(mytarget PRIVATE Qt6::CanvasPainter)`
Since: | Qt 6.11
Inherits: | QCanvasGradient

- List of all members, including inherited members

## Public Functions

| QCanvasLinearGradient()
| QCanvasLinearGradient(QPointF start, QPointF end)
| QCanvasLinearGradient(qreal startX, qreal startY, qreal endX, qreal endY)
| QCanvasLinearGradient(const QCanvasLinearGradient &)
| QCanvasLinearGradient(QCanvasLinearGradient &&)
| ~QCanvasLinearGradient()
QPointF | endPosition() const
void | setEndPosition(qreal x, qreal y)
void | setEndPosition(QPointF end)
void | setStartPosition(qreal x, qreal y)
void | setStartPosition(QPointF start)
QPointF | startPosition() const
QCanvasLinearGradient & | operator=(QCanvasLinearGradient &&)
QCanvasLinearGradient & | operator=(const QCanvasLinearGradient &)

## Detailed Description

Liner gradient interpolate colors between start and end points along a linear pattern, so horizontally, vertically or diagonally. The gradient starts from startPosition() and ends to endPosition(). Outside this area, the colors are the starting and the ending color.

Here is a simple example:

     QRectF rect1(0, 0, 200, 200);
     QCanvasLinearGradient lg(rect1.topLeft(),
                         rect1.bottomRight());
     lg.setColorAt(0.0, "#1a2a6c");
     lg.setColorAt(0.5, "#b21f1f");
     lg.setColorAt(1.0, "#fdbb2d");
     p->setFillStyle(lg);
     p->fillRect(rect1);

## Member Function Documentation

### QCanvasLinearGradient::QCanvasLinearGradient()

Constructs a default linear gradient. Gradient start color position is (0, 0) and end color position (0, 100).

### QCanvasLinearGradient::QCanvasLinearGradient(QPointF start, QPointF end)

Constructs a linear gradient. Gradient start color position is start and end color position end.

### QCanvasLinearGradient::QCanvasLinearGradient(qreal startX, qreal startY, qreal endX, qreal endY)

Constructs a linear gradient. Gradient start color position is (startX, startY) and end color position (endX, endY).

### `[constexpr noexcept default]` QCanvasLinearGradient::QCanvasLinearGradient(const QCanvasLinearGradient &)

Copy-constructs an instance of QCanvasLinearGradient.

### `[constexpr noexcept default]` QCanvasLinearGradient::QCanvasLinearGradient(QCanvasLinearGradient &&)

Move-constructs an instance of QCanvasLinearGradient.

### `[constexpr noexcept default]` QCanvasLinearGradient::~QCanvasLinearGradient()

Destroys the instance of QCanvasLinearGradient.

### QPointF QCanvasLinearGradient::endPosition() const

Returns the end point of linear gradient.

See also setEndPosition().

### void QCanvasLinearGradient::setEndPosition(qreal x, qreal y)

Sets the end point of linear gradient to ( x, y).

See also endPosition().

### void QCanvasLinearGradient::setEndPosition(QPointF end)

Sets the end point of linear gradient to end.

This is an overloaded function.

### void QCanvasLinearGradient::setStartPosition(qreal x, qreal y)

Sets the start point of linear gradient to ( x, y).

See also startPosition().

### void QCanvasLinearGradient::setStartPosition(QPointF start)

Sets the start point of linear gradient to start.

This is an overloaded function.

### QPointF QCanvasLinearGradient::startPosition() const

Returns the start point of linear gradient.

See also setStartPosition().

### `[noexcept default]` QCanvasLinearGradient &QCanvasLinearGradient::operator=(QCanvasLinearGradient &&)

Move-assigns other to this QCanvasLinearGradient instance.

### `[noexcept default]` QCanvasLinearGradient &QCanvasLinearGradient::operator=(const QCanvasLinearGradient &)

Copy-assigns other to this QCanvasLinearGradient instance.