Qt Documentation

Qt 5.14
Qt 3D
C++ Classes
QAlphaTest

QAlphaTest Class

(Qt3DRender::QAlphaTest)

The QAlphaTest class specify alpha reference test. More...

Header:	#include <QAlphaTest>
qmake:	QT += 3drender
Since:	Qt 5.7
Instantiated By:	AlphaTest
Inherits:	Qt3DRender::QRenderState

This class was introduced in Qt 5.7.

List of all members, including inherited members

Public Types

enum	AlphaFunction { Never, Always, Less, LessOrEqual, Equal, …, NotEqual }

Properties

alphaFunction : AlphaFunction
referenceValue : float

Public Functions

Qt3DRender::QAlphaTest::AlphaFunction	alphaFunction() const
float	referenceValue() const

Public Slots

void	setAlphaFunction(Qt3DRender::QAlphaTest::AlphaFunction alphaFunction)
void	setReferenceValue(float referenceValue)

Signals

void	alphaFunctionChanged(Qt3DRender::QAlphaTest::AlphaFunction alphaFunction)
void	referenceValueChanged(float referenceValue)

Detailed Description

As the OpenGL documentation explains; The alpha test discards a fragment conditional on the outcome of a comparison between the incoming fragment's alpha value and a constant reference value.

Member Type Documentation

enum QAlphaTest::AlphaFunction

Enumeration for the alpha function values

Constant	Value	Description
`Qt3DRender::QAlphaTest::Never`	`0x0200`	Never pass alpha test
`Qt3DRender::QAlphaTest::Always`	`0x0207`	Always pass alpha test
`Qt3DRender::QAlphaTest::Less`	`0x0201`	Pass alpha test if fragment alpha is less than reference value
`Qt3DRender::QAlphaTest::LessOrEqual`	`0x0203`	Pass alpha test if fragment alpha is less than or equal to reference value
`Qt3DRender::QAlphaTest::Equal`	`0x0202`	Pass alpha test if fragment alpha is equal to reference value
`Qt3DRender::QAlphaTest::GreaterOrEqual`	`0x0206`	Pass alpha test if fragment alpha is greater than or equal to reference value
`Qt3DRender::QAlphaTest::Greater`	`0x0204`	Pass alpha test if fragment alpha is greater than reference value
`Qt3DRender::QAlphaTest::NotEqual`	`0x0205`	Pass alpha test if fragment alpha is not equal to reference value

Property Documentation

alphaFunction : AlphaFunction

Holds the alpha function used by the alpha test. Default is Never.

Access functions:

Qt3DRender::QAlphaTest::AlphaFunction	alphaFunction() const
void	setAlphaFunction(Qt3DRender::QAlphaTest::AlphaFunction alphaFunction)

Notifier signal:

void	alphaFunctionChanged(Qt3DRender::QAlphaTest::AlphaFunction alphaFunction)

referenceValue : float

Holds the reference value used by the alpha test. Default is 0.0. When set, the value is clamped between 0 and 1.