The QPlatformWindowFormat class specifies the display format of an OpenGL rendering context and if possible attributes of the corresponding QPlatformWindow. More...

#include <qplatformwindowformat_qpa.h>

Public Types
enum	FormatOption { DoubleBuffer = 0x0001, DepthBuffer = 0x0002, Rgba = 0x0004, AlphaChannel = 0x0008, AccumBuffer = 0x0010, StencilBuffer = 0x0020, StereoBuffers = 0x0040, DirectRendering = 0x0080, HasOverlay = 0x0100, SampleBuffers = 0x0200, DeprecatedFunctions = 0x0400, HasWindowSurface = 0x0800, SingleBuffer = DoubleBuffer << 16, NoDepthBuffer = DepthBuffer << 16, ColorIndex = Rgba << 16, NoAlphaChannel = AlphaChannel << 16, NoAccumBuffer = AccumBuffer << 16, NoStencilBuffer = StencilBuffer << 16, NoStereoBuffers = StereoBuffers << 16, IndirectRendering = DirectRendering << 16, NoOverlay = HasOverlay << 16, NoSampleBuffers = SampleBuffers << 16, NoDeprecatedFunctions = DeprecatedFunctions << 16, NoWindowSurface = HasWindowSurface << 16 }

enum	WindowApi { Raster, OpenGL, OpenVG }

Public Functions
bool	accum () const
	Returns true if the accumulation buffer is enabled; otherwise returns false. More...

int	accumBufferSize () const
	Returns the accumulation buffer size. More...

bool	alpha () const
	Returns true if the alpha buffer in the framebuffer is enabled; otherwise returns false. More...

int	alphaBufferSize () const
	Returns the alpha buffer size. More...

int	blueBufferSize () const
	Returns the blue buffer size. More...

bool	depth () const
	Returns true if the depth buffer is enabled; otherwise returns false. More...

int	depthBufferSize () const
	Returns the depth buffer size. More...

bool	directRendering () const
	Returns true if direct rendering is enabled; otherwise returns false. More...

bool	doubleBuffer () const
	Returns true if double buffering is enabled; otherwise returns false. More...

int	greenBufferSize () const
	Returns the green buffer size. More...

bool	hasWindowSurface () const
	Returns true if the corresponding widget has an instance of QWindowSurface. More...

QPlatformWindowFormat &	operator= (const QPlatformWindowFormat &other)
	Assigns other to this object. More...

	QPlatformWindowFormat ()
	Constructs a QPlatformWindowFormat object with the following default settings: More...

	QPlatformWindowFormat (FormatOptions options)

	QPlatformWindowFormat (const QPlatformWindowFormat &other)
	Constructs a copy of other. More...

int	redBufferSize () const
	Returns the red buffer size. More...

bool	rgba () const
	Returns true if RGBA color mode is set. More...

bool	sampleBuffers () const
	Returns true if multisample buffer support is enabled; otherwise returns false. More...

int	samples () const
	Returns the number of samples per pixel when multisampling is enabled. More...

void	setAccum (bool enable)
	If enable is true enables the accumulation buffer; otherwise disables the accumulation buffer. More...

void	setAccumBufferSize (int size)
	Set the preferred accumulation buffer size, where size is the bit depth for each RGBA component. More...

void	setAlpha (bool enable)
	If enable is true enables the alpha buffer; otherwise disables the alpha buffer. More...

void	setAlphaBufferSize (int size)
	Set the preferred alpha buffer size to size. More...

void	setBlueBufferSize (int size)
	Set the preferred blue buffer size to size. More...

void	setDepth (bool enable)
	If enable is true enables the depth buffer; otherwise disables the depth buffer. More...

void	setDepthBufferSize (int size)
	Set the minimum depth buffer size to size. More...

void	setDirectRendering (bool enable)
	If enable is true enables direct rendering; otherwise disables direct rendering. More...

void	setDoubleBuffer (bool enable)
	If enable is true sets double buffering; otherwise sets single buffering. More...

void	setGreenBufferSize (int size)
	Set the preferred green buffer size to size. More...

void	setOption (QPlatformWindowFormat::FormatOptions opt)
	Sets the format option to opt. More...

void	setRedBufferSize (int size)
	Set the preferred red buffer size to size. More...

void	setRgba (bool enable)
	If enable is true sets RGBA mode. More...

void	setSampleBuffers (bool enable)
	If enable is true, a GL context with multisample buffer support is picked; otherwise ignored. More...

void	setSamples (int numSamples)
	Set the preferred number of samples per pixel when multisampling is enabled to numSamples. More...

void	setSharedContext (QPlatformGLContext *context)

void	setStencil (bool enable)
	If enable is true enables the stencil buffer; otherwise disables the stencil buffer. More...

void	setStencilBufferSize (int size)
	Set the preferred stencil buffer size to size. More...

void	setStereo (bool enable)
	If enable is true enables stereo buffering; otherwise disables stereo buffering. More...

void	setSwapInterval (int interval)
	Set the preferred swap interval. More...

void	setWindowApi (QPlatformWindowFormat::WindowApi api)

void	setWindowSurface (bool enable)
	If enable is true a top level QWidget will create a QWindowSurface at creation;. More...

QPlatformGLContext *	sharedGLContext () const

bool	stencil () const
	Returns true if the stencil buffer is enabled; otherwise returns false. More...

int	stencilBufferSize () const
	Returns the stencil buffer size. More...

bool	stereo () const
	Returns true if stereo buffering is enabled; otherwise returns false. More...

int	swapInterval () const
	Returns the currently set swap interval. More...

bool	testOption (QPlatformWindowFormat::FormatOptions opt) const
	Returns true if format option opt is set; otherwise returns false. More...

WindowApi	windowApi () const

	~QPlatformWindowFormat ()
	Destroys the QPlatformWindowFormat. More...

Static Public Functions
static QPlatformWindowFormat	defaultFormat ()
	Returns the default QPlatformWindowFormat for the application. More...

static void	setDefaultFormat (const QPlatformWindowFormat &f)
	Sets a new default QPlatformWindowFormat for the application to f. More...

Private Functions
void	detach ()

Properties
QPlatformWindowFormatPrivate *	d

Friends
Q_GUI_EXPORT bool	operator!= (const QPlatformWindowFormat &, const QPlatformWindowFormat &)
	Returns false if all the options of the two QPlatformWindowFormat objects a and b are equal; otherwise returns true. More...

Q_GUI_EXPORT QDebug	operator<< (QDebug, const QPlatformWindowFormat &)

Q_GUI_EXPORT bool	operator== (const QPlatformWindowFormat &, const QPlatformWindowFormat &)
	Sets a new default QPlatformWindowFormat for overlay contexts to f. More...

Detailed Description

The QPlatformWindowFormat class specifies the display format of an OpenGL rendering context and if possible attributes of the corresponding QPlatformWindow.

Since: 4.8

QWidget has a setter and getter function for QPlatformWindowFormat. These functions can be used by the application programmer to signal what kind of format he wants to the window and glcontext should have. However, it is not always possible to fulfill these requirements. The application programmer should therefore check the resulting QPlatformWindowFormat from QPlatformGLContext to see the format that was actually created.

A display format has several characteristics:

You can also specify preferred bit depths for the color buffer, depth buffer, alpha buffer, accumulation buffer and the stencil buffer with the functions: setRedBufferSize(), setGreenBufferSize(), setBlueBufferSize(), setDepthBufferSize(), setAlphaBufferSize(), setAccumBufferSize() and setStencilBufferSize().

Note that even if you specify that you prefer a 32 bit depth buffer (e.g. with setDepthBufferSize(32)), the format that is chosen may not have a 32 bit depth buffer, even if there is a format available with a 32 bit depth buffer. The main reason for this is how the system dependant picking algorithms work on the different platforms, and some format options may have higher precedence than others.

You create and tell a QPlatformWindowFormat object what rendering options you want from an OpenGL rendering context.

OpenGL drivers or accelerated hardware may or may not support advanced features such as alpha channel or stereographic viewing. If you request some features that the driver/hardware does not provide when you create a QGLWidget, you will get a rendering context with the nearest subset of features.

There are different ways to define the display characteristics of a rendering context. One is to create a QPlatformWindowFormat and make it the default for the entire application:

QGLFormat fmt;
fmt.setAlpha(true);
fmt.setStereo(true);
QGLFormat::setDefaultFormat(fmt);

Or you can specify the desired format when creating an object of your QGLWidget subclass:

QGLFormat fmt;
fmt.setDoubleBuffer(false);                 // single buffer
fmt.setDirectRendering(false);              // software rendering
MyGLWidget* myWidget = new MyGLWidget(fmt, ...);

After the widget has been created, you can find out which of the requested features the system was able to provide:

QGLFormat fmt;
fmt.setOverlay(true);
fmt.setStereo(true);
MyGLWidget* myWidget = new MyGLWidget(fmt, ...);
if (!myWidget->format().stereo()) {
    // ok, goggles off
    if (!myWidget->format().hasOverlay()) {
        qFatal("Cool hardware required");
    }
}

OpenGL is a trademark of Silicon Graphics, Inc. in the United States and other countries.

See also: QPlatformGLContext, QWidget

Definition at line 54 of file qplatformwindowformat_qpa.h.

Enumerations

◆ FormatOption

enum QPlatformWindowFormat::FormatOption

Enumerator
DoubleBuffer
DepthBuffer
Rgba
AlphaChannel
AccumBuffer
StencilBuffer
StereoBuffers
DirectRendering
HasOverlay
SampleBuffers
DeprecatedFunctions
HasWindowSurface
SingleBuffer
NoDepthBuffer
ColorIndex
NoAlphaChannel
NoAccumBuffer
NoStencilBuffer
NoStereoBuffers
IndirectRendering
NoOverlay
NoSampleBuffers
NoDeprecatedFunctions
NoWindowSurface

Definition at line 57 of file qplatformwindowformat_qpa.h.

                       {
         DoubleBuffer            = 0x0001,
         DepthBuffer             = 0x0002,
         Rgba                    = 0x0004,
         AlphaChannel            = 0x0008,
         AccumBuffer             = 0x0010,
         StencilBuffer           = 0x0020,
         StereoBuffers           = 0x0040,
         DirectRendering         = 0x0080,
         HasOverlay              = 0x0100,
         SampleBuffers           = 0x0200,
         DeprecatedFunctions     = 0x0400,
         HasWindowSurface        = 0x0800,
         SingleBuffer            = DoubleBuffer    << 16,
         NoDepthBuffer           = DepthBuffer     << 16,
         ColorIndex              = Rgba            << 16,
         NoAlphaChannel          = AlphaChannel    << 16,
         NoAccumBuffer           = AccumBuffer     << 16,
         NoStencilBuffer         = StencilBuffer   << 16,
         NoStereoBuffers         = StereoBuffers   << 16,
         IndirectRendering       = DirectRendering << 16,
         NoOverlay               = HasOverlay      << 16,
         NoSampleBuffers         = SampleBuffers   << 16,
         NoDeprecatedFunctions   = DeprecatedFunctions << 16,
         NoWindowSurface         = HasWindowSurface << 16
 
     };

◆ WindowApi

enum QPlatformWindowFormat::WindowApi

Enumerator
Raster
OpenGL
OpenVG

Definition at line 86 of file qplatformwindowformat_qpa.h.

                    {
         Raster,
         OpenGL,
         OpenVG
     };

Constructors and Destructors

◆ QPlatformWindowFormat() [1/3]

QPlatformWindowFormat::QPlatformWindowFormat ( )

Constructs a QPlatformWindowFormat object with the following default settings:

Double buffer: Enabled.
Depth buffer: Enabled.
RGBA: Enabled (i.e., color index disabled).
Alpha channel: Disabled.
Accumulator buffer: Disabled.
Stencil buffer: Enabled.
Stereo: Disabled.
Direct rendering: Enabled.
Multisample buffers: Disabled.

Definition at line 190 of file qplatformwindowformat_qpa.cpp.

 {
     d = new QPlatformWindowFormatPrivate;
 }

◆ QPlatformWindowFormat() [2/3]

QPlatformWindowFormat::QPlatformWindowFormat ( FormatOptions options )

◆ QPlatformWindowFormat() [3/3]

QPlatformWindowFormat::QPlatformWindowFormat ( const QPlatformWindowFormat & other )

Constructs a copy of other.

Definition at line 241 of file qplatformwindowformat_qpa.cpp.

 {
     d = other.d;
     d->ref.ref();
 }

◆ ~QPlatformWindowFormat()

QPlatformWindowFormat::~QPlatformWindowFormat ( )

Destroys the QPlatformWindowFormat.

Definition at line 265 of file qplatformwindowformat_qpa.cpp.

 {
     if (!d->ref.deref())
         delete d;
 }

Functions

◆ accum()

bool QPlatformWindowFormat::accum ( ) const

inline

Returns true if the accumulation buffer is enabled; otherwise returns false.

The accumulation buffer is disabled by default.

See also: setAccum(), setAccumBufferSize()

Definition at line 200 of file qplatformwindowformat_qpa.h.

Referenced by qglx_buildSpec(), and qglx_reducePlatformWindowFormat().

 {
     return testOption(QPlatformWindowFormat::AccumBuffer);
 }

◆ accumBufferSize()

int QPlatformWindowFormat::accumBufferSize ( ) const

Returns the accumulation buffer size.

See also: setAccumBufferSize(), accum(), setAccum()

Definition at line 879 of file qplatformwindowformat_qpa.cpp.

Referenced by qglx_buildSpec().

 {
    return d->accumSize;
 }

◆ alpha()

bool QPlatformWindowFormat::alpha ( ) const

inline

Returns true if the alpha buffer in the framebuffer is enabled; otherwise returns false.

The alpha buffer is disabled by default.

See also: setAlpha(), setAlphaBufferSize()

Definition at line 195 of file qplatformwindowformat_qpa.h.

Referenced by q_createConfigAttributesFromFormat(), qglx_buildSpec(), qglx_findConfig(), and qglx_reducePlatformWindowFormat().

 {
     return testOption(QPlatformWindowFormat::AlphaChannel);
 }

◆ alphaBufferSize()

int QPlatformWindowFormat::alphaBufferSize ( ) const

Returns the alpha buffer size.

See also: alpha(), setAlpha(), setAlphaBufferSize()

Definition at line 852 of file qplatformwindowformat_qpa.cpp.

Referenced by q_createConfigAttributesFromFormat(), QBBGLContext::QBBGLContext(), and qglx_buildSpec().

 {
    return d->alphaSize;
 }

◆ blueBufferSize()

int QPlatformWindowFormat::blueBufferSize ( ) const

Returns the blue buffer size.

Since: 4.2

See also: setBlueBufferSize()

Definition at line 825 of file qplatformwindowformat_qpa.cpp.

Referenced by QXlibWindow::correctColorBuffers(), QBBWindow::platformWindowFormatToNativeFormat(), q_createConfigAttributesFromFormat(), QBBGLContext::QBBGLContext(), and qglx_buildSpec().

 {
    return d->blueSize;
 }

◆ defaultFormat()

QPlatformWindowFormat QPlatformWindowFormat::defaultFormat ( )

static

Returns the default QPlatformWindowFormat for the application.

All QGLWidget objects that are created use this format unless another format is specified, e.g. when they are constructed.

If no special default format has been set using setDefaultFormat(), the default format is the same as that created with QPlatformWindowFormat().

See also: setDefaultFormat()

Definition at line 922 of file qplatformwindowformat_qpa.cpp.

Referenced by QEglFSScreen::createAndSetPlatformContext(), QWidgetPrivate::createTLExtra(), effectiveState(), and QBBIntegration::QBBIntegration().

 {
     return *q_platformwindow_default_format();
 }

◆ depth()

bool QPlatformWindowFormat::depth ( ) const

inline

Returns true if the depth buffer is enabled; otherwise returns false.

The depth buffer is enabled by default.

See also: setDepth(), setDepthBufferSize()

Definition at line 185 of file qplatformwindowformat_qpa.h.

Referenced by q_createConfigAttributesFromFormat(), qglx_buildSpec(), and qglx_reducePlatformWindowFormat().

 {
     return testOption(QPlatformWindowFormat::DepthBuffer);
 }

◆ depthBufferSize()

int QPlatformWindowFormat::depthBufferSize ( ) const

Returns the depth buffer size.

See also: depth(), setDepth(), setDepthBufferSize()

Definition at line 720 of file qplatformwindowformat_qpa.cpp.

Referenced by q_createConfigAttributesFromFormat(), and qglx_buildSpec().

 {
    return d->depthSize;
 }

◆ detach()

void QPlatformWindowFormat::detach ( )

private

Warning: This function is not part of the public interface.

Definition at line 227 of file qplatformwindowformat_qpa.cpp.

 {
     if (d->ref != 1) {
         QPlatformWindowFormatPrivate *newd = new QPlatformWindowFormatPrivate(d);
         if (!d->ref.deref())
             delete d;
         d = newd;
     }
 }

◆ directRendering()

bool QPlatformWindowFormat::directRendering ( ) const

inline

Returns true if direct rendering is enabled; otherwise returns false.

Direct rendering is enabled by default.

See also: setDirectRendering()

Definition at line 215 of file qplatformwindowformat_qpa.h.

 {
     return testOption(QPlatformWindowFormat::DirectRendering);
 }

◆ doubleBuffer()

bool QPlatformWindowFormat::doubleBuffer ( ) const

inline

Returns true if double buffering is enabled; otherwise returns false.

Double buffering is enabled by default.

See also: setDoubleBuffer()

Definition at line 180 of file qplatformwindowformat_qpa.h.

Referenced by qglx_buildSpec(), and qglx_reducePlatformWindowFormat().

 {
     return testOption(QPlatformWindowFormat::DoubleBuffer);
 }

◆ greenBufferSize()

int QPlatformWindowFormat::greenBufferSize ( ) const

Returns the green buffer size.

Since: 4.2

See also: setGreenBufferSize()

Definition at line 790 of file qplatformwindowformat_qpa.cpp.

Referenced by QXlibWindow::correctColorBuffers(), QBBWindow::platformWindowFormatToNativeFormat(), q_createConfigAttributesFromFormat(), QBBGLContext::QBBGLContext(), and qglx_buildSpec().

 {
    return d->greenSize;
 }

◆ hasWindowSurface()

bool QPlatformWindowFormat::hasWindowSurface ( ) const

inline

Returns true if the corresponding widget has an instance of QWindowSurface.

Otherwise returns false.

WindowSurface is enabled by default.

Definition at line 220 of file qplatformwindowformat_qpa.h.

 {
     return testOption(QPlatformWindowFormat::HasWindowSurface);
 }

◆ operator=()

QPlatformWindowFormat & QPlatformWindowFormat::operator= ( const QPlatformWindowFormat & other )

Assigns other to this object.

Definition at line 251 of file qplatformwindowformat_qpa.cpp.

 {
     if (d != other.d) {
         other.d->ref.ref();
         if (!d->ref.deref())
             delete d;
         d = other.d;
     }
     return *this;
 }

◆ redBufferSize()

int QPlatformWindowFormat::redBufferSize ( ) const

Returns the red buffer size.

Since: 4.2

See also: setRedBufferSize()

Definition at line 755 of file qplatformwindowformat_qpa.cpp.

Referenced by QXlibWindow::correctColorBuffers(), QBBWindow::platformWindowFormatToNativeFormat(), q_createConfigAttributesFromFormat(), QBBGLContext::QBBGLContext(), and qglx_buildSpec().

 {
    return d->redSize;
 }

◆ rgba()

bool QPlatformWindowFormat::rgba ( ) const

inline

Returns true if RGBA color mode is set.

Returns false if color index mode is set. The default color mode is RGBA.

See also: setRgba()

Definition at line 190 of file qplatformwindowformat_qpa.h.

Referenced by qglx_buildSpec().

 {
     return testOption(QPlatformWindowFormat::Rgba);
 }

◆ sampleBuffers()

bool QPlatformWindowFormat::sampleBuffers ( ) const

inline

Returns true if multisample buffer support is enabled; otherwise returns false.

The multisample buffer is disabled by default.

See also: setSampleBuffers()

Definition at line 225 of file qplatformwindowformat_qpa.h.

Referenced by q_createConfigAttributesFromFormat(), qglx_buildSpec(), qglx_platformWindowFromGLXFBConfig(), and qglx_reducePlatformWindowFormat().

 {
     return testOption(QPlatformWindowFormat::SampleBuffers);
 }

◆ samples()

int QPlatformWindowFormat::samples ( ) const

Returns the number of samples per pixel when multisampling is enabled.

By default, the highest number of samples that is available is used.

See also: setSampleBuffers(), sampleBuffers(), setSamples()

Definition at line 557 of file qplatformwindowformat_qpa.cpp.

Referenced by q_createConfigAttributesFromFormat(), and qglx_buildSpec().

 {
    return d->numSamples;
 }

◆ setAccum()

void QPlatformWindowFormat::setAccum ( bool enable )

If enable is true enables the accumulation buffer; otherwise disables the accumulation buffer.

The accumulation buffer is disabled by default.

The accumulation buffer is used to create blur effects and multiple exposures.

See also: accum(), setAccumBufferSize()

Definition at line 427 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), and qglx_reducePlatformWindowFormat().

 {
     setOption(enable ? QPlatformWindowFormat::AccumBuffer : QPlatformWindowFormat::NoAccumBuffer);
 }

◆ setAccumBufferSize()

void QPlatformWindowFormat::setAccumBufferSize ( int size )

Set the preferred accumulation buffer size, where size is the bit depth for each RGBA component.

See also: accum(), setAccum(), accumBufferSize()

Definition at line 863 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), QDirectFbGLContext::QDirectFbGLContext(), qglx_platformWindowFromGLXFBConfig(), and qt_qPlatformWindowFormatFromConfig().

 {
     detach();
     if (size < 0) {
         qWarning("QPlatformWindowFormat::setAccumBufferSize: Cannot set negative accumulate buffer size %d", size);
         return;
     }
     d->accumSize = size;
     setAccum(size > 0);
 }

◆ setAlpha()

void QPlatformWindowFormat::setAlpha ( bool enable )

If enable is true enables the alpha buffer; otherwise disables the alpha buffer.

The alpha buffer is disabled by default.

The alpha buffer is typically used for implementing transparency or translucency. The A in RGBA specifies the transparency of a pixel.

See also: alpha(), setAlphaBufferSize()

Definition at line 397 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), effectiveState(), qDeleteQGLContext(), QDirectFbGLContext::QDirectFbGLContext(), and qglx_reducePlatformWindowFormat().

 {
     setOption(enable ? QPlatformWindowFormat::AlphaChannel : QPlatformWindowFormat::NoAlphaChannel);
 }

◆ setAlphaBufferSize()

void QPlatformWindowFormat::setAlphaBufferSize ( int size )

Set the preferred alpha buffer size to size.

This function implicitly enables the alpha channel.

See also: setRedBufferSize(), setGreenBufferSize(), alphaBufferSize()

Definition at line 836 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), QBBGLContext::QBBGLContext(), QDirectFbGLContext::QDirectFbGLContext(), qglx_platformWindowFromGLXFBConfig(), and qt_qPlatformWindowFormatFromConfig().

 {
     detach();
     if (size < 0) {
         qWarning("QPlatformWindowFormat::setAlphaBufferSize: Cannot set negative alpha buffer size %d", size);
         return;
     }
     d->alphaSize = size;
     setAlpha(size > 0);
 }

◆ setBlueBufferSize()

void QPlatformWindowFormat::setBlueBufferSize ( int size )

Set the preferred blue buffer size to size.

Since: 4.2

See also: setRedBufferSize(), setGreenBufferSize(), setAlphaBufferSize()

Definition at line 805 of file qplatformwindowformat_qpa.cpp.

Referenced by QXlibWindow::correctColorBuffers(), QEglFSScreen::createAndSetPlatformContext(), EAGLPlatformContext::EAGLPlatformContext(), QBBGLContext::QBBGLContext(), QDirectFbGLContext::QDirectFbGLContext(), qglx_platformWindowFromGLXFBConfig(), QOpenKODEWindow::QOpenKODEWindow(), and qt_qPlatformWindowFormatFromConfig().

 {
     detach();
     if (size < 0) {
         qWarning("QPlatformWindowFormat::setBlueBufferSize: Cannot set negative blue buffer size %d", size);
         return;
     }
     d->blueSize = size;
 }

◆ setDefaultFormat()

void QPlatformWindowFormat::setDefaultFormat ( const QPlatformWindowFormat & f )

static

Sets a new default QPlatformWindowFormat for the application to f.

For example, to set single buffering as the default instead of double buffering, your main() might contain code like this:

QApplication a(argc, argv);
QGLFormat f;
f.setDoubleBuffer(false);
QGLFormat::setDefaultFormat(f);

See also: defaultFormat()

Definition at line 936 of file qplatformwindowformat_qpa.cpp.

Referenced by QBBIntegration::QBBIntegration().

 {
     *q_platformwindow_default_format() = f;
 }

◆ setDepth()

void QPlatformWindowFormat::setDepth ( bool enable )

If enable is true enables the depth buffer; otherwise disables the depth buffer.

The depth buffer is enabled by default.

The purpose of a depth buffer (or Z-buffering) is to remove hidden surfaces. Pixels are assigned Z values based on the distance to the viewer. A pixel with a high Z value is closer to the viewer than a pixel with a low Z value. This information is used to decide whether to draw a pixel or not.

See also: depth(), setDepthBufferSize()

Definition at line 332 of file qplatformwindowformat_qpa.cpp.

Referenced by QEglFSScreen::createAndSetPlatformContext(), EAGLPlatformContext::EAGLPlatformContext(), and qglx_reducePlatformWindowFormat().

 {
     setOption(enable ? QPlatformWindowFormat::DepthBuffer : QPlatformWindowFormat::NoDepthBuffer);
 }

◆ setDepthBufferSize()

void QPlatformWindowFormat::setDepthBufferSize ( int size )

Set the minimum depth buffer size to size.

See also: depthBufferSize(), setDepth(), depth()

Definition at line 704 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), QDirectFbGLContext::QDirectFbGLContext(), qglx_platformWindowFromGLXFBConfig(), and qt_qPlatformWindowFormatFromConfig().

 {
     detach();
     if (size < 0) {
         qWarning("QPlatformWindowFormat::setDepthBufferSize: Cannot set negative depth buffer size %d", size);
         return;
     }
     d->depthSize = size;
     setDepth(size > 0);
 }

◆ setDirectRendering()

void QPlatformWindowFormat::setDirectRendering ( bool enable )

If enable is true enables direct rendering; otherwise disables direct rendering.

Direct rendering is enabled by default.

Enabling this option will make OpenGL bypass the underlying window system and render directly from hardware to the screen, if this is supported by the system.

See also: directRendering()

Definition at line 520 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), qglx_platformWindowFromGLXFBConfig(), and qt_qPlatformWindowFormatFromConfig().

 {
     setOption(enable ? QPlatformWindowFormat::DirectRendering : QPlatformWindowFormat::IndirectRendering);
 }

◆ setDoubleBuffer()

void QPlatformWindowFormat::setDoubleBuffer ( bool enable )

If enable is true sets double buffering; otherwise sets single buffering.

Double buffering is enabled by default.

Double buffering is a technique where graphics are rendered on an off-screen buffer and not directly to the screen. When the drawing has been completed, the program calls a swapBuffers() function to exchange the screen contents with the buffer. The result is flicker-free drawing and often better performance.

See also: doubleBuffer(), QGLContext::swapBuffers(), QGLWidget::swapBuffers()

Definition at line 299 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), QDirectFbGLContext::QDirectFbGLContext(), and qglx_reducePlatformWindowFormat().

 {
     setOption(enable ? QPlatformWindowFormat::DoubleBuffer : QPlatformWindowFormat::SingleBuffer);
 }

◆ setGreenBufferSize()

void QPlatformWindowFormat::setGreenBufferSize ( int size )

Set the preferred green buffer size to size.

Since: 4.2

See also: setRedBufferSize(), setBlueBufferSize(), setAlphaBufferSize()

Definition at line 770 of file qplatformwindowformat_qpa.cpp.

Referenced by QXlibWindow::correctColorBuffers(), QEglFSScreen::createAndSetPlatformContext(), EAGLPlatformContext::EAGLPlatformContext(), QBBGLContext::QBBGLContext(), QDirectFbGLContext::QDirectFbGLContext(), qglx_platformWindowFromGLXFBConfig(), QOpenKODEWindow::QOpenKODEWindow(), and qt_qPlatformWindowFormatFromConfig().

 {
     detach();
     if (size < 0) {
         qWarning("QPlatformWindowFormat::setGreenBufferSize: Cannot set negative green buffer size %d", size);
         return;
     }
     d->greenSize = size;
 }

◆ setOption()

void QPlatformWindowFormat::setOption ( QPlatformWindowFormat::FormatOptions opt )

Sets the format option to opt.

See also: testOption()

Definition at line 674 of file qplatformwindowformat_qpa.cpp.

 {
     detach();
     if (opt & 0xffff)
         d->opts |= opt;
     else
        d->opts &= ~(opt >> 16);
 }

◆ setRedBufferSize()

void QPlatformWindowFormat::setRedBufferSize ( int size )

Set the preferred red buffer size to size.

Since: 4.2

See also: setGreenBufferSize(), setBlueBufferSize(), setAlphaBufferSize()

Definition at line 735 of file qplatformwindowformat_qpa.cpp.

Referenced by QXlibWindow::correctColorBuffers(), QEglFSScreen::createAndSetPlatformContext(), EAGLPlatformContext::EAGLPlatformContext(), QBBGLContext::QBBGLContext(), QDirectFbGLContext::QDirectFbGLContext(), qglx_platformWindowFromGLXFBConfig(), QOpenKODEWindow::QOpenKODEWindow(), and qt_qPlatformWindowFormatFromConfig().

 {
     detach();
     if (size < 0) {
         qWarning("QPlatformWindowFormat::setRedBufferSize: Cannot set negative red buffer size %d", size);
         return;
     }
     d->redSize = size;
 }

◆ setRgba()

void QPlatformWindowFormat::setRgba ( bool enable )

If enable is true sets RGBA mode.

If enable is false sets color index mode.

The default color mode is RGBA.

RGBA is the preferred mode for most OpenGL applications. In RGBA color mode you specify colors as red + green + blue + alpha quadruplets.

In color index mode you specify an index into a color lookup table.

See also: rgba()

Definition at line 366 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), qglx_platformWindowFromGLXFBConfig(), and qt_qPlatformWindowFormatFromConfig().

 {
     setOption(enable ? QPlatformWindowFormat::Rgba : QPlatformWindowFormat::ColorIndex);
 }

◆ setSampleBuffers()

void QPlatformWindowFormat::setSampleBuffers ( bool enable )

If enable is true, a GL context with multisample buffer support is picked; otherwise ignored.

See also: sampleBuffers(), setSamples(), samples()

Definition at line 545 of file qplatformwindowformat_qpa.cpp.

Referenced by QEglFSScreen::createAndSetPlatformContext(), EAGLPlatformContext::EAGLPlatformContext(), qglx_platformWindowFromGLXFBConfig(), and qglx_reducePlatformWindowFormat().

 {
     setOption(enable ? QPlatformWindowFormat::SampleBuffers : QPlatformWindowFormat::NoSampleBuffers);
 }

◆ setSamples()

void QPlatformWindowFormat::setSamples ( int numSamples )

Set the preferred number of samples per pixel when multisampling is enabled to numSamples.

By default, the highest number of samples available is used.

See also: setSampleBuffers(), sampleBuffers(), samples()

Definition at line 569 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), qglx_platformWindowFromGLXFBConfig(), and qt_qPlatformWindowFormatFromConfig().

 {
     detach();
     if (numSamples < 0) {
         qWarning("QPlatformWindowFormat::setSamples: Cannot have negative number of samples per pixel %d", numSamples);
         return;
     }
     d->numSamples = numSamples;
     setSampleBuffers(numSamples > 0);
 }

◆ setSharedContext()

void QPlatformWindowFormat::setSharedContext ( QPlatformGLContext * context )

Definition at line 632 of file qplatformwindowformat_qpa.cpp.

Referenced by qDeleteQGLContext(), and QWaylandGLContext::QWaylandGLContext().

 {
     d->sharedContext = context;
 }

◆ setStencil()

void QPlatformWindowFormat::setStencil ( bool enable )

If enable is true enables the stencil buffer; otherwise disables the stencil buffer.

The stencil buffer is enabled by default.

The stencil buffer masks certain parts of the drawing area so that masked parts are not drawn on.

See also: stencil(), setStencilBufferSize()

Definition at line 457 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), and qglx_reducePlatformWindowFormat().

 {
     setOption(enable ? QPlatformWindowFormat::StencilBuffer: QPlatformWindowFormat::NoStencilBuffer);
 }

◆ setStencilBufferSize()

void QPlatformWindowFormat::setStencilBufferSize ( int size )

Set the preferred stencil buffer size to size.

See also: stencilBufferSize(), setStencil(), stencil()

Definition at line 889 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), QDirectFbGLContext::QDirectFbGLContext(), qglx_platformWindowFromGLXFBConfig(), and qt_qPlatformWindowFormatFromConfig().

 {
     detach();
     if (size < 0) {
         qWarning("QPlatformWindowFormat::setStencilBufferSize: Cannot set negative stencil buffer size %d", size);
         return;
     }
     d->stencilSize = size;
     setStencil(size > 0);
 }

◆ setStereo()

void QPlatformWindowFormat::setStereo ( bool enable )

If enable is true enables stereo buffering; otherwise disables stereo buffering.

Stereo buffering is disabled by default.

Stereo buffering provides extra color buffers to generate left-eye and right-eye images.

See also: stereo()

Definition at line 487 of file qplatformwindowformat_qpa.cpp.

Referenced by EAGLPlatformContext::EAGLPlatformContext(), QDirectFbGLContext::QDirectFbGLContext(), qglx_platformWindowFromGLXFBConfig(), qglx_reducePlatformWindowFormat(), and qt_qPlatformWindowFormatFromConfig().

 {
     setOption(enable ? QPlatformWindowFormat::StereoBuffers : QPlatformWindowFormat::NoStereoBuffers);
 }

◆ setSwapInterval()

void QPlatformWindowFormat::setSwapInterval ( int interval )

Set the preferred swap interval.

Since: 4.2

This can be used to sync the GL drawing into a system window to the vertical refresh of the screen. Setting an interval value of 0 will turn the vertical refresh syncing off, any value higher than 0 will turn the vertical syncing on.

Under Windows and under X11, where the WGL_EXT_swap_control and GLX_SGI_video_sync extensions are used, the interval parameter can be used to set the minimum number of video frames that are displayed before a buffer swap will occur. In effect, setting the interval to 10, means there will be 10 vertical retraces between every buffer swap.

Under Windows the WGL_EXT_swap_control extension has to be present, and under X11 the GLX_SGI_video_sync extension has to be present.

Definition at line 601 of file qplatformwindowformat_qpa.cpp.

 {
     detach();
     d->swapInterval = interval;
 }

◆ setWindowApi()

void QPlatformWindowFormat::setWindowApi ( QPlatformWindowFormat::WindowApi api )

Definition at line 621 of file qplatformwindowformat_qpa.cpp.

Referenced by QEglFSScreen::createAndSetPlatformContext(), EAGLPlatformContext::EAGLPlatformContext(), QBBIntegration::QBBIntegration(), and qDeleteQGLContext().

 {
     detach();
     d->windowApi = api;
 }

◆ setWindowSurface()

void QPlatformWindowFormat::setWindowSurface ( bool enable )

If enable is true a top level QWidget will create a QWindowSurface at creation;.

otherwise the QWidget will only have a QPlatformWindow.

This is useful for QGLWidget where the QPlatformGLContext controls the surface.

Definition at line 663 of file qplatformwindowformat_qpa.cpp.

Referenced by qDeleteQGLContext().

 {
     setOption(enable ? QPlatformWindowFormat::HasWindowSurface : QPlatformWindowFormat::NoWindowSurface);
 }

◆ sharedGLContext()

QPlatformGLContext * QPlatformWindowFormat::sharedGLContext ( ) const

Definition at line 637 of file qplatformwindowformat_qpa.cpp.

Referenced by QXlibWindow::glContext(), QGLXContext::QGLXContext(), and QWaylandGLContext::QWaylandGLContext().

 {
     return d->sharedContext;
 }

◆ stencil()

bool QPlatformWindowFormat::stencil ( ) const

inline

Returns true if the stencil buffer is enabled; otherwise returns false.

The stencil buffer is enabled by default.

See also: setStencil(), setStencilBufferSize()

Definition at line 205 of file qplatformwindowformat_qpa.h.

Referenced by q_createConfigAttributesFromFormat(), qglx_buildSpec(), and qglx_reducePlatformWindowFormat().

 {
     return testOption(QPlatformWindowFormat::StencilBuffer);
 }

◆ stencilBufferSize()

int QPlatformWindowFormat::stencilBufferSize ( ) const

Returns the stencil buffer size.

See also: stencil(), setStencil(), setStencilBufferSize()

Definition at line 905 of file qplatformwindowformat_qpa.cpp.

Referenced by q_createConfigAttributesFromFormat(), and qglx_buildSpec().

 {
    return d->stencilSize;
 }

◆ stereo()

bool QPlatformWindowFormat::stereo ( ) const

inline

Returns true if stereo buffering is enabled; otherwise returns false.

Stereo buffering is disabled by default.

See also: setStereo()

Definition at line 210 of file qplatformwindowformat_qpa.h.

Referenced by qglx_buildSpec(), and qglx_reducePlatformWindowFormat().

 {
     return testOption(QPlatformWindowFormat::StereoBuffers);
 }

◆ swapInterval()

int QPlatformWindowFormat::swapInterval ( ) const

Returns the currently set swap interval.

Since: 4.2

-1 is returned if setting the swap interval isn't supported in the system GL implementation.

Definition at line 616 of file qplatformwindowformat_qpa.cpp.

 {
     return d->swapInterval;
 }

◆ testOption()

bool QPlatformWindowFormat::testOption ( QPlatformWindowFormat::FormatOptions opt ) const

Returns true if format option opt is set; otherwise returns false.

See also: setOption()

Definition at line 691 of file qplatformwindowformat_qpa.cpp.

 {
     if (opt & 0xffff)
        return (d->opts & opt) != 0;
     else
        return (d->opts & (opt >> 16)) == 0;
 }

◆ windowApi()

QPlatformWindowFormat::WindowApi QPlatformWindowFormat::windowApi ( ) const

Definition at line 627 of file qplatformwindowformat_qpa.cpp.

Referenced by QBBWindow::glContext(), q_configFromQPlatformWindowFormat(), QBBGLContext::QBBGLContext(), and QBBWindow::QBBWindow().

 {
     return d->windowApi;
 }

Friends and Related Functions

◆ operator!=

bool operator!=	(	const QPlatformWindowFormat &	a,
		const QPlatformWindowFormat &	b
	)

friend

Returns false if all the options of the two QPlatformWindowFormat objects a and b are equal; otherwise returns true.

Since: 4.8

Definition at line 1036 of file qplatformwindowformat_qpa.cpp.

 {
     return !(a == b);
 }

◆ operator<<

Q_GUI_EXPORT QDebug operator<<	(	QDebug	,
		const QPlatformWindowFormat &
	)

friend

Definition at line 1042 of file qplatformwindowformat_qpa.cpp.

 {
     const QPlatformWindowFormatPrivate * const d = f.d;
 
     dbg.nospace() << "QGLFormat("
                   << "options " << d->opts
                   << ", depthBufferSize " << d->depthSize
                   << ", accumBufferSize " << d->accumSize
                   << ", stencilBufferSize " << d->stencilSize
                   << ", redBufferSize " << d->redSize
                   << ", greenBufferSize " << d->greenSize
                   << ", blueBufferSize " << d->blueSize
                   << ", alphaBufferSize " << d->alphaSize
                   << ", samples " << d->numSamples
                   << ", swapInterval " << d->swapInterval
                   << ')';
 
     return dbg.space();
 }

◆ operator==

bool operator==	(	const QPlatformWindowFormat &	a,
		const QPlatformWindowFormat &	b
	)

friend

Sets a new default QPlatformWindowFormat for overlay contexts to f.

This format is used whenever a QGLWidget is created with a format that hasOverlay() enabled.

For example, to get a double buffered overlay context (if available), use code like this:

QGLFormat f = QGLFormat::defaultOverlayFormat();
f.setDoubleBuffer(true);
QGLFormat::setDefaultOverlayFormat(f);

As usual, you can find out after widget creation whether the underlying OpenGL system was able to provide the requested specification:

// ...continued from above
MyGLWidget* myWidget = new MyGLWidget(QGLFormat(QGL::HasOverlay), ...);
if (myWidget->format().hasOverlay()) {
    // Yes, we got an overlay, let's check _its_ format:
    QGLContext* olContext = myWidget->overlayContext();
    if (olContext->format().doubleBuffer())
        ; // yes, we got a double buffered overlay
    else
        ; // no, only single buffered overlays are available
}

See also: defaultOverlayFormat()

Returns true if all the options of the two QPlatformWindowFormat objects a and b are equal; otherwise returns false.

Since: 4.8

Definition at line 1008 of file qplatformwindowformat_qpa.cpp.

 {
     return (a.d == b.d) || ((int) a.d->opts == (int) b.d->opts
         && a.d->alphaSize == b.d->alphaSize
         && a.d->accumSize == b.d->accumSize
         && a.d->stencilSize == b.d->stencilSize
         && a.d->depthSize == b.d->depthSize
         && a.d->redSize == b.d->redSize
         && a.d->greenSize == b.d->greenSize
         && a.d->blueSize == b.d->blueSize
         && a.d->numSamples == b.d->numSamples
         && a.d->swapInterval == b.d->swapInterval
         && a.d->windowApi == b.d->windowApi);
 }

Properties

◆ d

QPlatformWindowFormatPrivate* QPlatformWindowFormat::d

private

Definition at line 160 of file qplatformwindowformat_qpa.h.

Referenced by operator<<(), operator=(), and QPlatformWindowFormat().

The documentation for this class was generated from the following files:

/src/gui/kernel/qplatformwindowformat_qpa.h
/src/gui/kernel/qplatformwindowformat_qpa.cpp

Public Types

Public Functions

Static Public Functions

Private Functions

Properties

Friends

Detailed Description

Enumerations

◆ FormatOption

◆ WindowApi

Constructors and Destructors

◆ QPlatformWindowFormat() [1/3]

◆ QPlatformWindowFormat() [2/3]

◆ QPlatformWindowFormat() [3/3]

◆ ~QPlatformWindowFormat()

Functions

◆ accum()

◆ accumBufferSize()

◆ alpha()

◆ alphaBufferSize()

◆ blueBufferSize()

◆ defaultFormat()

◆ depth()

◆ depthBufferSize()

◆ detach()

◆ directRendering()

◆ doubleBuffer()

◆ greenBufferSize()

◆ hasWindowSurface()

◆ operator=()

◆ redBufferSize()

◆ rgba()

◆ sampleBuffers()

◆ samples()

◆ setAccum()

◆ setAccumBufferSize()

◆ setAlpha()

◆ setAlphaBufferSize()

◆ setBlueBufferSize()

◆ setDefaultFormat()

◆ setDepth()

◆ setDepthBufferSize()

◆ setDirectRendering()

◆ setDoubleBuffer()

◆ setGreenBufferSize()

◆ setOption()

◆ setRedBufferSize()

◆ setRgba()

◆ setSampleBuffers()

◆ setSamples()

◆ setSharedContext()

◆ setStencil()

◆ setStencilBufferSize()

◆ setStereo()

◆ setSwapInterval()

◆ setWindowApi()

◆ setWindowSurface()

◆ sharedGLContext()

◆ stencil()

◆ stencilBufferSize()

◆ stereo()

◆ swapInterval()

◆ testOption()

◆ windowApi()

Friends and Related Functions

◆ operator!=

◆ operator<<

◆ operator==

Properties

◆ d