Q3DSSurfaceViewer Class | Qt 3D Studio Runtime 2.0

Qt 3D Studio Runtime | C++ Classes | Q3DSSurfaceViewer

Qt 3D Studio Runtime 2.0 Manual

# Q3DSSurfaceViewer Class

Renders a Qt 3D Studio presentation on a QWindow or an offscreen render target using OpenGL. More...

Header: | #include <Q3DSSurfaceViewer>
Since: | Qt 3D Studio 2.0
Inherits: | QObject

- List of all members, including inherited members

## Properties

- autoSize : bool
- error : const QString
- running : const bool

- size : QSize
- updateInterval : int

- 1 property inherited from QObject

## Public Functions

| Q3DSSurfaceViewer(QObject *parent = nullptr)
virtual | ~Q3DSSurfaceViewer()
bool | autoSize() const
QOpenGLContext * | context() const
bool | create(QSurface *surface, QOpenGLContext *context)
bool | create(QSurface *surface, QOpenGLContext *context, uint fboId)
void | destroy()
QString | error() const
uint | fboId() const
QImage | grab(const QRect &rect = QRect())
bool | isRunning() const
Q3DSPresentation * | presentation() const
void | setAutoSize(bool autoSize)
void | setSize(const QSize &size)
void | setUpdateInterval(int interval)
Q3DSViewerSettings * | settings() const
QSize | size() const
QSurface * | surface() const
int | updateInterval() const

- 34 public functions inherited from QObject

## Public Slots

void | update()

- 1 public slot inherited from QObject

## Signals

void | autoSizeChanged()
void | errorChanged()
void | frameUpdate()
void | presentationLoaded()
void | runningChanged()
void | sizeChanged()
void | updateIntervalChanged()

- 2 signals inherited from QObject

## Protected Functions

| Q3DSSurfaceViewer(Q3DSSurfaceViewerPrivate &dd, QObject *parent)

- 9 protected functions inherited from QObject

### Additional Inherited Members

- 1 public variable inherited from QObject
- 10 static public members inherited from QObject
- 2 protected variables inherited from QObject

## Detailed Description

Renders a Qt 3D Studio presentation on a QWindow or an offscreen render target using OpenGL.

Q3DSSurfaceViewer is used to render Qt 3D Studio presentations onto a QSurface. In practice this means two types of uses: rendering to an on-screen QWindow, or rendering to an offscreen render target (typically an OpenGL texture via a framebuffer object and a QOffscreenSurface).

#### Example Usage

      int main(int argc, char *argv[])
      {
          QGuiApplication app(argc, argv);

          QOpenGLContext context;
          context.create();

          QWindow window;
          window.setSurfaceType(QSurface::OpenGLSurface);
          window.setFormat(context.format());
          window.create();

          Q3DSSurfaceViewer viewer;
          viewer.presentation()->setSource(QUrl(QStringLiteral("qrc:/my_presentation.uip")));
          viewer.setUpdateInterval(0); // enable automatic updates

          // Register a scene object for slide management (optional)
          Q3DSSceneElement scene(viewer.presentation(), QStringLiteral("Scene"));

          // Register an element object for attribute setting (optional)
          Q3DSElement element(viewer.presentation(), QStringLiteral("myCarModel"));

          viewer.create(&window, &context);

          w.resize(1024, 768);
          w.show();

          return app.exec();
      }

See also Q3DSWidget.

## Property Documentation

### autoSize : bool

Specifies whether the viewer should change the size of the presentation automatically to match the surface size when surface size changes. The size property is updated automatically whenever the viewer is updated if this property value is `true`.

When rendering offscreen, via a QOffscreenSurface, this property must be set to `false` by the application since it is then up to the application to provide a QOpenGLFramebufferObject with the desired size. The size of the Q3DSSurfaceViewer must be set to the same value.

The default value is `true`.

Access functions:

bool | autoSize() const
void | setAutoSize(bool autoSize)

Notifier signal:

void | autoSizeChanged()

### error : const QString

Contains the text for the error message that was generated during the loading of the presentation. When no error occurred or there is no presentation loaded, the value is an empty string.

This property is read-only.

Access functions:

QString | error() const

Notifier signal:

void | errorChanged()

### running : const bool

The value of this property is `true` when the presentation has been loaded and is ready to be shown.

This property is read-only.

Access functions:

bool | isRunning() const

Notifier signal:

void | runningChanged()

### size : QSize

Holds the desired size of the presentation. Relevant only when autoSize is set to `false`.

Access functions:

QSize | size() const
void | setSize(const QSize &size)

Notifier signal:

void | sizeChanged()

See also autoSize.

### updateInterval : int

Holds the viewer update interval in milliseconds. If the value is negative, the viewer doesn't update the presentation automatically.

The default value is -1, meaning there are no automatic updates and update() must be called manually.

Access functions:

int | updateInterval() const
void | setUpdateInterval(int interval)

Notifier signal:

void | updateIntervalChanged()

See also update().

## Member Function Documentation

### Q3DSSurfaceViewer::Q3DSSurfaceViewer(QObject *parent = nullptr)

Default constructs an instance of Q3DSSurfaceViewer.

### `[protected]` Q3DSSurfaceViewer::Q3DSSurfaceViewer(Q3DSSurfaceViewerPrivate &dd, QObject *parent)

Default constructs an instance of Q3DSSurfaceViewer.

### `[virtual]` Q3DSSurfaceViewer::~Q3DSSurfaceViewer()

Destroys the instance of Q3DSSurfaceViewer. The destructor is virtual.

### QOpenGLContext *Q3DSSurfaceViewer::context() const

Returns the context given in initialization.

See also create().

### bool Q3DSSurfaceViewer::create(QSurface *surface, QOpenGLContext *context)

Initializes Q3DSSurfaceViewer to render the presentation to the given surface using the context.

The source property of the attached presentation must be set before the viewer can be initialized.

Returns whether the initialization succeeded.

See also running, Q3DSPresentation::source, and presentation().

### bool Q3DSSurfaceViewer::create(QSurface *surface, QOpenGLContext *context, uint fboId)

Initializes Q3DSSurfaceViewer to render the presentation to the given surface using the context and optional framebuffer id (fboId). If fboId is omitted, it defaults to zero.

The source property of the attached presentation must be set before the viewer can be initialized.

Returns whether the initialization succeeded.

See also running, Q3DSPresentation::source, and presentation().

### void Q3DSSurfaceViewer::destroy()

Releases the presentation and all related resources.

The Q3DSSurfaceViewer instance can be reused by calling create() again.

### uint Q3DSSurfaceViewer::fboId() const

Returns the framebuffer id given in initialization.

See also create().

### `[signal]` void Q3DSSurfaceViewer::frameUpdate()

This signal is emitted each time a frame has been rendered.

### QImage Q3DSSurfaceViewer::grab(const QRect &rect = QRect())

Grabs the data rendered to the framebuffer into an image using the given rect. The rect parameter is optional. If it is omitted, the whole framebuffer is captured.

Note: This is a potentially expensive operation.

### Q3DSPresentation *Q3DSSurfaceViewer::presentation() const

Returns the presentation object used by the Q3DSSurfaceViewer.

### `[signal]` void Q3DSSurfaceViewer::presentationLoaded()

This signal is emitted when the presentation has been loaded and is ready to be shown.

### Q3DSViewerSettings *Q3DSSurfaceViewer::settings() const

Returns the settings object used by the Q3DSSurfaceViewer.

### QSurface *Q3DSSurfaceViewer::surface() const

Returns the surface given in initialization.

See also create().

### `[slot]` void Q3DSSurfaceViewer::update()

Updates the surface viewer with a new frame.