- Qt 6.12
- Qt GUI
- C++ Classes
- QRgba64
- Qt 6.12.0 Reference Documentation

# QRgba64 Class

The QRgba64 struct contains a 64-bit RGB color. More...

Header: | `#include <QRgba64>`
CMake: | `find_package(Qt6 REQUIRED COMPONENTS Gui)` `target_link_libraries(mytarget PRIVATE Qt6::Gui)`
qmake: | `QT += gui`

- List of all members, including inherited members
- QRgba64 is part of Painting Classes.

## Public Functions

| QRgba64()
quint8 | alpha8() const
quint16 | alpha() const
quint8 | blue8() const
quint16 | blue() const
quint8 | green8() const
quint16 | green() const
bool | isOpaque() const
bool | isTransparent() const
QRgba64 | premultiplied() const
quint8 | red8() const
quint16 | red() const
void | setAlpha(quint16 alpha)
void | setBlue(quint16 blue)
void | setGreen(quint16 green)
void | setRed(quint16 red)
uint | toArgb32() const
ushort | toRgb16() const
QRgba64 | unpremultiplied() const
| operator quint64() const
QRgba64 & | operator=(quint64 rgba)

## Static Public Members

QRgba64 | fromArgb32(uint rgb)
QRgba64 | fromRgba64(quint64 c)
QRgba64 | fromRgba64(quint16 r, quint16 g, quint16 b, quint16 a)
QRgba64 | fromRgba(quint8 red, quint8 green, quint8 blue, quint8 alpha)

## Related Non-Members

`(since 6.11.1)` size_t | qHash(QRgba64 key, size_t seed = 0)

## Detailed Description

QRgba64 is a 64-bit data-structure containing four 16-bit color channels: Red, green, blue and alpha.

QRgba64 can be used as a replacement for QRgb when higher precision is needed. In particular a premultiplied QRgba64 can operate on unpremultiplied QRgb without loss of precision except for alpha 0.

See also QRgb and QColor.

## Member Function Documentation

### `[constexpr noexcept default]` QRgba64::QRgba64()

Default-constructs an instance of QRgba64.

### `[constexpr]` quint8 QRgba64::alpha8() const

Returns the alpha channel as an 8-bit.

### `[constexpr]` quint16 QRgba64::alpha() const

Returns the 16-bit alpha channel.

See also setAlpha().

### `[constexpr]` quint8 QRgba64::blue8() const

Returns the blue color component as an 8-bit.

### `[constexpr]` quint16 QRgba64::blue() const

Returns the 16-bit blue color component.

See also setBlue().

### `[static constexpr]` QRgba64 QRgba64::fromArgb32(uint rgb)

Constructs a QRgba64 value from the 32bit ARGB value rgb.

See also fromRgba().

### `[static constexpr]` QRgba64 QRgba64::fromRgba64(quint64 c)

Returns c as a QRgba64 struct.

See also fromArgb32().

### `[static constexpr]` QRgba64 QRgba64::fromRgba64(quint16 r, quint16 g, quint16 b, quint16 a)

Returns the QRgba64 quadruplet (r, g, b, a).

See also fromRgba().

### `[static constexpr]` QRgba64 QRgba64::fromRgba(quint8 red, quint8 green, quint8 blue, quint8 alpha)

Constructs a QRgba64 value from the four 8-bit color channels red, green, blue and alpha.

See also fromArgb32().

### `[constexpr]` quint8 QRgba64::green8() const

Returns the green color component as an 8-bit.

### `[constexpr]` quint16 QRgba64::green() const

Returns the 16-bit green color component.

See also setGreen().

### `[constexpr]` bool QRgba64::isOpaque() const

Returns whether the color is fully opaque.

See also isTransparent() and alpha().

### `[constexpr]` bool QRgba64::isTransparent() const

Returns whether the color is transparent.

See also isOpaque() and alpha().

### `[constexpr]` QRgba64 QRgba64::premultiplied() const

Returns the color with the alpha premultiplied.

See also unpremultiplied().

### `[constexpr]` quint8 QRgba64::red8() const

Returns the red color component as an 8-bit.

### `[constexpr]` quint16 QRgba64::red() const

Returns the 16-bit red color component.

See also setRed().

### void QRgba64::setAlpha(quint16 alpha)

Sets the alpha of this color to alpha.

See also alpha().

### void QRgba64::setBlue(quint16 blue)

Sets the blue color component of this color to blue.

See also blue().

### void QRgba64::setGreen(quint16 green)

Sets the green color component of this color to green.

See also green().

### void QRgba64::setRed(quint16 red)

Sets the red color component of this color to red.

See also red().

### `[constexpr]` uint QRgba64::toArgb32() const

Returns the color as a 32-bit ARGB value.

See also fromArgb32().

### `[constexpr]` ushort QRgba64::toRgb16() const

Returns the color as a 16-bit RGB value.

See also toArgb32().

### `[constexpr]` QRgba64 QRgba64::unpremultiplied() const

Returns the color with the alpha unpremultiplied.

See also premultiplied().

### `[constexpr]` QRgba64::operator quint64() const

Returns the color as a 64bit unsigned integer

### `[noexcept]` QRgba64 &QRgba64::operator=(quint64 rgba)

Assigns the value rgba to this instance of QRgba64 and returns it.

## Related Non-Members

### `[constexpr noexcept, since 6.11.1]` size_t qHash(QRgba64 key, size_t seed = 0)

Returns the hash value for key, using seed to seed the calculation.

In Qt versions prior to 6.11.1, the type was hashable via its implicit conversion to quint64. This explicit qHash() overload retains compatibility with that implicit qHash().

This function was introduced in Qt 6.11.1.