- Qt 6.9
- Qt GUI
- C++ Classes
- QColorTransform
- Qt 6.9.3 Reference Documentation

# QColorTransform Class

The QColorTransform class is a transformation between color spaces. More...

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

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

## Public Functions

`(since 6.4)` bool | isIdentity() const
QRgb | map(QRgb argb) const
QRgba64 | map(QRgba64 rgba64) const
`(since 6.4)` QRgbaFloat16 | map(QRgbaFloat16 rgbafp16) const
`(since 6.4)` QRgbaFloat32 | map(QRgbaFloat32 rgbafp32) const
QColor | map(const QColor &color) const

## Related Non-Members

`(since 6.4)` bool | operator!=(const QColorTransform &ct1, const QColorTransform &ct2)
`(since 6.4)` bool | operator==(const QColorTransform &ct1, const QColorTransform &ct2)

## Detailed Description

QColorTransform is an instantiation of a transformation between color spaces. It can be applied on color and pixels to convert them from one color space to another.

To create a QColorTransform, use QColorSpace::transformationToColorSpace():

     QColorSpace sourceColorSpace(QColorSpace::SRgb);
     QColorSpace targetColorSpace(QColorSpace::DisplayP3);
     QColorTransform srgbToP3Transform = sourceColorSpace.transformationToColorSpace(targetColorSpace);

Setting up a QColorTransform takes some preprocessing, so keeping around QColorTransforms that you need often is recommended, instead of generating them on the fly.

## Member Function Documentation

### `[noexcept, since 6.4]` bool QColorTransform::isIdentity() const

Returns true if the color transform is the identity transform.

This function was introduced in Qt 6.4.

### QRgb QColorTransform::map(QRgb argb) const

Applies the color transformation on the QRgb value argb.

The input should be opaque or unpremultiplied.

### QRgba64 QColorTransform::map(QRgba64 rgba64) const

Applies the color transformation on the QRgba64 value rgba64.

The input should be opaque or unpremultiplied.

### `[since 6.4]` QRgbaFloat16 QColorTransform::map(QRgbaFloat16 rgbafp16) const

Applies the color transformation on the QRgbaFloat16 value rgbafp16.

The input should be opaque or unpremultiplied.

This function was introduced in Qt 6.4.

### `[since 6.4]` QRgbaFloat32 QColorTransform::map(QRgbaFloat32 rgbafp32) const

Applies the color transformation on the QRgbaFloat32 value rgbafp32.

The input should be opaque or unpremultiplied.

This function was introduced in Qt 6.4.

### QColor QColorTransform::map(const QColor &color) const

Applies the color transformation on the QColor value color.

## Related Non-Members

### `[since 6.4]` bool operator!=(const QColorTransform &ct1, const QColorTransform &ct2)

Returns true if ct1 does not define the same transformation as ct2.

This function was introduced in Qt 6.4.

### `[since 6.4]` bool operator==(const QColorTransform &ct1, const QColorTransform &ct2)

Returns true if ct1 defines the same color transformation as ct2.

This function was introduced in Qt 6.4.