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

Public Types

enum AlphaFunction { Never, Always, Less, LessOrEqual, ..., NotEqual }

Properties

Public Functions

QAlphaTest(Qt3DCore::QNode *parent = nullptr)
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)

Static Public Members

const QMetaObject staticMetaObject

Additional Inherited Members

  • 1 public variable inherited from QObject
  • 2 protected functions inherited from Qt3DCore::QNode
  • 9 protected functions inherited from QObject
  • 2 protected variables inherited from QObject

Detailed Description

The QAlphaTest class specify alpha reference test.

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

ConstantValueDescription
Qt3DRender::QAlphaTest::Never0x0200Never pass alpha test
Qt3DRender::QAlphaTest::Always0x0207Always pass alpha test
Qt3DRender::QAlphaTest::Less0x0201Pass alpha test if fragment alpha is less than reference value
Qt3DRender::QAlphaTest::LessOrEqual0x0203Pass alpha test if fragment alpha is less than or equal to reference value
Qt3DRender::QAlphaTest::Equal0x0202Pass alpha test if fragment alpha is equal to reference value
Qt3DRender::QAlphaTest::GreaterOrEqual0x0206Pass alpha test if fragment alpha is greater than or equal to reference value
Qt3DRender::QAlphaTest::Greater0x0204Pass alpha test if fragment alpha is greater than reference value
Qt3DRender::QAlphaTest::NotEqual0x0205Pass 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.

Access functions:

float referenceValue() const
void setReferenceValue(float referenceValue)

Notifier signal:

void referenceValueChanged(float referenceValue)

Member Function Documentation

QAlphaTest::QAlphaTest(Qt3DCore::QNode *parent = nullptr)

Default constructs an instance of QAlphaTest.

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