SoQtRenderArea Class Reference

The SoQtRenderArea class adds scenegraph handling and event management. More...

#include <Inventor/Qt/SoQtRenderArea.h>

Inheritance diagram for SoQtRenderArea:

Public Member Functions
	SoQtRenderArea (QWidget *parent=NULL, const char *name=NULL, SbBool embed=TRUE, SbBool mouseInput=TRUE, SbBool keyboardInput=TRUE)
	~SoQtRenderArea ()
virtual void	setSceneGraph (SoNode *scene)
virtual SoNode *	getSceneGraph (void)
void	setOverlaySceneGraph (SoNode *scene)
SoNode *	getOverlaySceneGraph (void)
void	setBackgroundColor (const SbColor &color)
const SbColor &	getBackgroundColor (void) const
void	setBackgroundIndex (int idx)
int	getBackgroundIndex (void) const
void	setOverlayBackgroundIndex (int idx)
int	getOverlayBackgroundIndex (void) const
void	setColorMap (int start, int num, const SbColor *colors)
void	setOverlayColorMap (int start, int num, const SbColor *colors)
void	setViewportRegion (const SbViewportRegion &newRegion)
const SbViewportRegion &	getViewportRegion (void) const
void	setTransparencyType (SoGLRenderAction::TransparencyType type)
SoGLRenderAction::TransparencyType	getTransparencyType (void) const
void	setAntialiasing (SbBool smoothing, int numPasses)
void	getAntialiasing (SbBool &smoothing, int &numPasses) const
void	setClearBeforeRender (SbBool enable, SbBool zbEnable=TRUE)
SbBool	isClearBeforeRender (void) const
SbBool	isClearZBufferBeforeRender (void) const
void	setClearBeforeOverlayRender (SbBool enable)
SbBool	isClearBeforeOverlayRender (void) const
void	setAutoRedraw (SbBool enable)
SbBool	isAutoRedraw (void) const
void	setRedrawPriority (uint32_t priority)
uint32_t	getRedrawPriority (void) const
void	render (void)
void	renderOverlay (void)
void	scheduleRedraw (void)
void	scheduleOverlayRedraw (void)
void	redrawOnSelectionChange (SoSelection *selection)
void	redrawOverlayOnSelectionChange (SoSelection *selection)
void	setEventCallback (SoQtRenderAreaEventCB *func, void *user=NULL)
void	setSceneManager (SoSceneManager *manager)
SoSceneManager *	getSceneManager (void) const
void	setOverlaySceneManager (SoSceneManager *manager)
SoSceneManager *	getOverlaySceneManager (void) const
void	setGLRenderAction (SoGLRenderAction *action)
SoGLRenderAction *	getGLRenderAction (void) const
void	setOverlayGLRenderAction (SoGLRenderAction *action)
SoGLRenderAction *	getOverlayGLRenderAction (void) const
SbBool	sendSoEvent (const SoEvent *event)
void	registerDevice (SoQtDevice *device)
void	unregisterDevice (SoQtDevice *device)
Public Member Functions inherited from SoQtGLWidget
void	setBorder (const SbBool enable)
SbBool	isBorder (void) const
virtual void	setDoubleBuffer (const SbBool enable)
SbBool	isDoubleBuffer (void) const
void	setDrawToFrontBufferEnable (const SbBool enable)
SbBool	isDrawToFrontBufferEnable (void) const
void	setQuadBufferStereo (const SbBool enable)
SbBool	isQuadBufferStereo (void) const
void	setAccumulationBuffer (const SbBool enable)
SbBool	getAccumulationBuffer (void) const
void	setStencilBuffer (const SbBool enable)
SbBool	getStencilBuffer (void) const
void	setAlphaChannel (const SbBool enable)
SbBool	getAlphaChannel (void) const
void	setOverlayRender (const SbBool onoff)
SbBool	isOverlayRender (void) const
void	setSampleBuffers (const int numsamples)
int	getSampleBuffers (void) const
void	setStealFocus (SbBool enable)
SbBool	isStealFocus (void) const
QWidget *	getGLWidget (void) const
QWidget *	getNormalWidget (void) const
QWidget *	getOverlayWidget (void) const
SbBool	hasOverlayGLArea (void) const
SbBool	hasNormalGLArea (void) const
unsigned long	getOverlayTransparentPixel (void)
void	getPointSizeLimits (SbVec2f &range, float &granularity)
void	getLineWidthLimits (SbVec2f &range, float &granularity)
Public Member Functions inherited from SoQtComponent
virtual	~SoQtComponent ()
virtual void	show (void)
virtual void	hide (void)
virtual void	setComponentCursor (const SoQtCursor &cursor)
SbBool	isFullScreen (void) const
SbBool	setFullScreen (const SbBool onoff)
SbBool	isVisible (void)
SbBool	isTopLevelShell (void) const
QWidget *	getWidget (void) const
QWidget *	getBaseWidget (void) const
QWidget *	getShellWidget (void) const
QWidget *	getParentWidget (void) const
void	setSize (const SbVec2s size)
SbVec2s	getSize (void) const
void	setTitle (const char *const title)
const char *	getTitle (void) const
void	setIconTitle (const char *const title)
const char *	getIconTitle (void) const
const char *	getWidgetName (void) const
const char *	getClassName (void) const
void	setWindowCloseCallback (SoQtComponentCB *const func, void *const user=NULL)
Public Member Functions inherited from SoQtObject
virtual SoType	getTypeId (void) const =0
SbBool	isOfType (SoType type) const

Static Public Member Functions
static uint32_t	getDefaultRedrawPriority (void)
Static Public Member Functions inherited from SoQtComponent
static void	setWidgetCursor (QWidget *w, const SoQtCursor &cursor)
static SoQtComponent *	getComponent (QWidget *widget)
static void	initClasses (void)
Static Public Member Functions inherited from SoQtObject
static void	initClass (void)
static SoType	getClassTypeId (void)
static void	init (void)

Protected Member Functions
	SoQtRenderArea (QWidget *parent, const char *name, SbBool embed, SbBool mouseInput, SbBool keyboardInput, SbBool build)
virtual void	redraw (void)
virtual void	actualRedraw (void)
virtual void	redrawOverlay (void)
virtual void	actualOverlayRedraw (void)
virtual SbBool	processSoEvent (const SoEvent *const event)
virtual void	processEvent (QEvent *event)
virtual void	initGraphic (void)
virtual void	initOverlayGraphic (void)
virtual void	sizeChanged (const SbVec2s &size)
virtual void	widgetChanged (QWidget *widget)
virtual void	afterRealizeHook (void)
QWidget *	buildWidget (QWidget *parent)
virtual const char *	getDefaultWidgetName (void) const
virtual const char *	getDefaultTitle (void) const
virtual const char *	getDefaultIconTitle (void) const
virtual SbBool	glScheduleRedraw (void)
Protected Member Functions inherited from SoQtGLWidget
	SoQtGLWidget (QWidget *const parent=NULL, const char *const name=NULL, const SbBool embed=TRUE, const int glmodes=SO_GL_RGB, const SbBool build=TRUE)
	~SoQtGLWidget ()
QWidget *	buildWidget (QWidget *parent)
void	setGLSize (const SbVec2s size)
SbVec2s	getGLSize (void) const
float	getGLAspectRatio (void) const
void	setGlxSize (const SbVec2s size)
SbVec2s	getGlxSize (void) const
float	getGlxAspectRatio (void) const
void	setStereoBuffer (SbBool flag)
SbBool	isStereoBuffer (void) const
SbBool	isRGBMode (void)
void	glLockNormal (void)
void	glUnlockNormal (void)
void	glLockOverlay (void)
void	glUnlockOverlay (void)
void	glSwapBuffers (void)
void	glFlushBuffer (void)
Protected Member Functions inherited from SoQtComponent
	SoQtComponent (QWidget *const parent=NULL, const char *const name=NULL, const SbBool embed=TRUE)
void	setClassName (const char *const name)
void	setBaseWidget (QWidget *widget)
void	registerWidget (QWidget *widget)
void	unregisterWidget (QWidget *widget)
void	addVisibilityChangeCallback (SoQtComponentVisibilityCB *const func, void *const user=NULL)
void	removeVisibilityChangeCallback (SoQtComponentVisibilityCB *const func, void *const user=NULL)

Additional Inherited Members
Protected Attributes inherited from SoQtGLWidget
SbBool	waitForExpose
SbBool	drawToFrontBuffer

Detailed Description

The SoQtRenderArea class adds scenegraph handling and event management.

The SoQtRenderArea class is a component that adds scenegraph management and input device event handling to the SoQtGLWidget component.

The class has many convenient methods for controlling aspects of the rendering, like for instance transparency, aliasing and for scheduling of redraws.

Native toolkit events are caught by SoQtRenderArea components, translated to Coin SoEvent instances and passed on to the scenegraph, in case the user is doing interactive operations on for instance Coin geometry draggers.

SoQtRenderArea is the first non-abstract component in it's inheritance hierarchy that you can use directly from client application code to set up a scenegraph viewer canvas.

For an SoQtRenderArea component to properly display your scenegraph, it must contain an SoCamera-derived node and at least one SoLight-derived lightsource node.

Here's a complete, stand-alone example on how to set up an SoQtRenderArea with a scenegraph:

#include <Inventor/Qt/SoQt.h>
#include <Inventor/Qt/SoQtRenderArea.h>

#include <Inventor/nodes/SoCube.h>
#include <Inventor/nodes/SoRotor.h>
#include <Inventor/nodes/SoArray.h>
#include <Inventor/nodes/SoDirectionalLight.h>
#include <Inventor/nodes/SoPerspectiveCamera.h>
#include <Inventor/nodes/SoSeparator.h>

// Set up a simple scenegraph, just for demonstration purposes.
static SoSeparator *
get_scene_graph(void)
{
  SoSeparator * root = new SoSeparator;

  SoGroup * group = new SoGroup;

  SoRotor * rotor = new SoRotor;
  rotor->rotation = SbRotation(SbVec3f(0.2, 0.5, 0.9), M_PI/4.0);
  group->addChild(rotor);

  SoCube * cube = new SoCube;
  group->addChild(cube);

  SoArray * array = new SoArray;
  array->origin = SoArray::CENTER;
  array->addChild(group);
  array->numElements1 = 2;
  array->numElements2 = 2;
  array->separation1 = SbVec3f(4, 0, 0);
  array->separation2 = SbVec3f(0, 4, 0);

  root->addChild(array);
  return root;
}

int
main(int argc, char ** argv)
{
  QWidget* window = SoQt::init(argv[0]);

  SoSeparator * root = new SoSeparator;
  root->ref();

  SoPerspectiveCamera * camera;
  root->addChild(camera = new SoPerspectiveCamera);

  root->addChild(new SoDirectionalLight);

  SoSeparator * userroot = get_scene_graph();
  root->addChild(userroot);

  SoQtRenderArea * renderarea = new SoQtRenderArea(window);
  camera->viewAll(userroot, renderarea->getViewportRegion());
  renderarea->setSceneGraph(root);
  renderarea->setBackgroundColor(SbColor(0.0f, 0.2f, 0.3f));
  if (argc > 1) {
    renderarea->setTitle(argv[1]);
    renderarea->setIconTitle(argv[1]);
  }
  renderarea->show();

  SoQt::show(window);
  SoQt::mainLoop();

  delete renderarea;
  root->unref();

  return 0;
}

Constructor & Destructor Documentation

SoQtRenderArea() [1/2]

SoQtRenderArea::SoQtRenderArea	(	QWidget *	parent = NULL,
		const char *	name = NULL,
		SbBool	embed = TRUE,
		SbBool	mouseInput = TRUE,
		SbBool	keyboardInput = TRUE
	)

Public constructor.

~SoQtRenderArea()

SoQtRenderArea::~SoQtRenderArea

(

)

Destructor.

SoQtRenderArea() [2/2]

SoQtRenderArea::SoQtRenderArea ( QWidget *  parent, const char *  name, SbBool  embed, SbBool  mouseInput, SbBool  keyboardInput, SbBool  build  )

protected

Protected constructor used by derived classes.

Member Function Documentation

setSceneGraph()

void SoQtRenderArea::setSceneGraph ( SoNode *  scene )

virtual

This method sets the scene graph to be rendered in the normal bitmap planes.

See also

getSceneGraph(), setOverlaySceneGraph()

Reimplemented in SoQtViewer.

getSceneGraph()

SoNode * SoQtRenderArea::getSceneGraph ( void  )

virtual

This method returns a reference to the scene graph root node as set by the user.

See also

SoQtRenderArea::getSceneManager()

Reimplemented in SoQtViewer.

setOverlaySceneGraph()

void SoQtRenderArea::setOverlaySceneGraph

(

SoNode *

scene

)

This method sets the scene graph to render for the overlay bitmap planes.

It will automatically take care of setting up overplay planes in the OpenGL canvas if the OpenGL hardware and driver supports it.

Important note: not all graphics hardware and / or drivers for graphics hardware support overlay planes, so application programmers are adviced to find some other way of accomplishing what they want to do before resorting to using overlay planes. Using overlay planes will in practice severely limit the portability of applications which depend on them being available.

See also

setSceneGraph(), getOverlaySceneGraph()

getOverlaySceneGraph()

SoNode * SoQtRenderArea::getOverlaySceneGraph

(

void

)

This method returns the scene graph for the overlay scene.

setBackgroundColor()

void SoQtRenderArea::setBackgroundColor

(

const SbColor &

color

)

This method sets the background color of the scene.

getBackgroundColor()

const SbColor & SoQtRenderArea::getBackgroundColor

(

void

)

const

This method returns the background color for the scene.

setBackgroundIndex()

void SoQtRenderArea::setBackgroundIndex

(

int

idx

)

This method sets the index of the background color for the scene.

getBackgroundIndex()

int SoQtRenderArea::getBackgroundIndex

(

void

)

const

This method returns the index of the background color for the scene.

setOverlayBackgroundIndex()

void SoQtRenderArea::setOverlayBackgroundIndex

(

int

idx

)

This method sets the index of the background for the overlay scene.

getOverlayBackgroundIndex()

int SoQtRenderArea::getOverlayBackgroundIndex

(

void

)

const

This method returns the index of the background for the overlay scene.

setColorMap()

void SoQtRenderArea::setColorMap	(	int	start,
		int	num,
		const SbColor *	colors
	)

This method sets the colormap for the scene.

setOverlayColorMap()

void SoQtRenderArea::setOverlayColorMap	(	int	start,
		int	num,
		const SbColor *	colors
	)

This method sets the colormap for the overlay scene.

setViewportRegion()

void SoQtRenderArea::setViewportRegion

(

const SbViewportRegion &

region

)

This method sets the viewport region.

getViewportRegion()

const SbViewportRegion & SoQtRenderArea::getViewportRegion

(

void

)

const

This method returns the viewport region.

setTransparencyType()

void SoQtRenderArea::setTransparencyType

(

SoGLRenderAction::TransparencyType

type

)

This method sets the transparency type to be used for the scene.

getTransparencyType()

SoGLRenderAction::TransparencyType SoQtRenderArea::getTransparencyType

(

void

)

const

This method returns the transparency type used for the scene.

setAntialiasing()

void SoQtRenderArea::setAntialiasing	(	SbBool	smoothing,
		int	numPasses
	)

This method sets the antialiasing used for the scene.

The smoothing flag signifies whether or not line and point aliasing should be turned on. See documentation of SoGLRenderAction::setSmoothing(), which will be called from this function.

numPasses gives the number of re-renderings to do of the scene, blending together the results from slight "jitters" of the camera view, into the OpenGL accumulation buffer. For further information, see documentation of SoGLRenderAction::setNumPasses() and SoQtGLWidget::setAccumulationBuffer().

getAntialiasing()

void SoQtRenderArea::getAntialiasing	(	SbBool &	smoothing,
		int &	numPasses
	)		const

This method returns the antialiasing used for the scene.

setClearBeforeRender()

void SoQtRenderArea::setClearBeforeRender	(	SbBool	enable,
		SbBool	zbEnable = TRUE
	)

This method sets whether the render buffer should be cleared before rendering.

The first argument specifies whether or not to clear out the pixels in the buffer, the second argument specifies whether or not the z-buffer values should be cleared between renderings.

Setting the first argument to FALSE can for instance be used when you want to clear out the buffer yourself, for instance by drawing a background image "under" the 3D scene rendered by Coin / Inventor.

isClearBeforeRender()

SbBool SoQtRenderArea::isClearBeforeRender

(

void

)

const

This method returns whether the render buffer is cleared before each render.

isClearZBufferBeforeRender()

SbBool SoQtRenderArea::isClearZBufferBeforeRender

(

void

)

const

This method returns whether the render buffer's Z buffer is cleared before each render.

setClearBeforeOverlayRender()

void SoQtRenderArea::setClearBeforeOverlayRender

(

SbBool

enable

)

This method sets whether the overlay render buffer should be cleared before each render or not.

isClearBeforeOverlayRender()

SbBool SoQtRenderArea::isClearBeforeOverlayRender

(

void

)

const

This method returns whether the overlay render buffer is cleared before each redraw or not.

setAutoRedraw()

void SoQtRenderArea::setAutoRedraw

(

SbBool

enable

)

This method sets whether redrawing should be handled automatically or not when data in the scenegraph changes.

The default setting causes the renderarea to automatically trigger a redraw of the scenegraph contents.

isAutoRedraw()

SbBool SoQtRenderArea::isAutoRedraw

(

void

)

const

This method returns whether redrawing is handled automatically not.

setRedrawPriority()

void SoQtRenderArea::setRedrawPriority

(

uint32_t

priority

)

This method sets the redraw priority.

getRedrawPriority()

uint32_t SoQtRenderArea::getRedrawPriority

(

void

)

const

This method returns the redraw priority.

getDefaultRedrawPriority()

uint32_t SoQtRenderArea::getDefaultRedrawPriority ( void  )

static

This function returns the default redraw priority.

render()

void SoQtRenderArea::render

(

void

)

This method causes the immediate rendering of the scene, by calling SoQtRenderArea::redraw().

renderOverlay()

void SoQtRenderArea::renderOverlay

(

void

)

This method renders the overlay scene.

scheduleRedraw()

void SoQtRenderArea::scheduleRedraw

(

void

)

This method schedules a redraw to happen at a later time (when the application has processed it's other events first).

scheduleOverlayRedraw()

void SoQtRenderArea::scheduleOverlayRedraw

(

void

)

This method schedules a redraw of the overlay scene.

redrawOnSelectionChange()

void SoQtRenderArea::redrawOnSelectionChange

(

SoSelection *

selection

)

Do automatic redraw of the scenegraph when a selection under the SoSelection node is changed.

Pass NULL to deactivate.

(Only one SoSelection node can be monitored at any given time. This is obviously a rather silly design flaw. We choose to match the original Inventor API here, but this will probably change in the next major revision of the library.)

redrawOverlayOnSelectionChange()

void SoQtRenderArea::redrawOverlayOnSelectionChange

(

SoSelection *

selection

)

Do automatic redraw of the scenegraph in the overlay planes when a selection under the SoSelection node is changed.

Pass NULL to deactivate.

See also

SoQtRenderArea::redrawOnSelectionChange()

setEventCallback()

void SoQtRenderArea::setEventCallback	(	SoQtRenderAreaEventCB *	func,
		void *	user = NULL
	)

This method sets the render area event callback.

setSceneManager()

void SoQtRenderArea::setSceneManager

(

SoSceneManager *

manager

)

This method sets the normal scene SoSceneManager object.

The previous set scene manager is deleted, and there is no way to currently avoid that. This might change in the future.

getSceneManager()

SoSceneManager * SoQtRenderArea::getSceneManager

(

void

)

const

This method returns the normal scene SoSceneManager object.

Having a reference to the SoSceneManager instance is useful for getting at the real root node of the rendering scenegraph, including camera, headlight and miscellaneous drawstyle nodes. The getSceneGraph() method will only return the user scenegrah for SoQtRenderArea subclass SoQtViewer and further subclasses. The reason this is not always what you want is because certain actions (like the SoRayPickAction) needs to traverse a valid camera if it should work as expected.

If you need to get a pointer to the real root node use this method to get the SoSceneManager instance reference used by the SoQtRenderArea, then use SoSceneManager::getSceneGraph() to get the root node Coin uses for rendering.

setOverlaySceneManager()

void SoQtRenderArea::setOverlaySceneManager

(

SoSceneManager *

manager

)

This method sets the overlay scene SoSceneManager object.

The previous set scene manager is not freed and will leak unless the user frees it.

getOverlaySceneManager()

SoSceneManager * SoQtRenderArea::getOverlaySceneManager

(

void

)

const

This method returns the overlay scene SoSceneManager object.

setGLRenderAction()

void SoQtRenderArea::setGLRenderAction

(

SoGLRenderAction *

action

)

This method sets the SoGLRenderAction object for the normal scene.

getGLRenderAction()

SoGLRenderAction * SoQtRenderArea::getGLRenderAction

(

void

)

const

This method returns the SoGLRenderAction object for the normal scene.

setOverlayGLRenderAction()

void SoQtRenderArea::setOverlayGLRenderAction

(

SoGLRenderAction *

action

)

This method sets the SoGLRenderAction object for rendering the overlay scenegraph.

getOverlayGLRenderAction()

SoGLRenderAction * SoQtRenderArea::getOverlayGLRenderAction

(

void

)

const

This method returns the SoGLRenderAction object for the overlay scene graph.

sendSoEvent()

SbBool SoQtRenderArea::sendSoEvent

(

const SoEvent *

event

)

This method posts and processes an SoEvent object to the SoQtRenderArea-based component and returns the result value from the event handler. This is a synchronous operation.

registerDevice()

void SoQtRenderArea::registerDevice

(

SoQtDevice *

device

)

This method adds device to the list of devices handling events for this component.

unregisterDevice()

void SoQtRenderArea::unregisterDevice

(

SoQtDevice *

device

)

This method removes device from the list of devices handling events for this component.

redraw()

void SoQtRenderArea::redraw ( void  )

protectedvirtual

This method is called from the render() method and takes care of setting up the context for OpenGL rendering (by making the OpenGL canvas the current context and specifying either the front or back buffer for rendering, depending on whether we're in singlebuffer or doublebuffer mode).

After setting up the OpenGL context, it calls actualRedraw() for the actual scenegraph rendering to take place.

Finally, the OpenGL buffers are either swapped back-to-front (for doublebuffering) or flushed (for singlebuffering), and our OpenGL context is unlocked.

The application programmer may override this method if extreme low-level control of the rendering process is necessary. Usually, you should be able to get away with overriding actualRedraw() for special cases, though.

Implements SoQtGLWidget.

actualRedraw()

void SoQtRenderArea::actualRedraw ( void  )

protectedvirtual

This method instantly redraws the normal (non-overlay) scenegraph by calling SoSceneManager::render().

Subclasses may override this method to add their own rendering before or after Coin renders it's scenegraph.

The following is a complete example that demonstrates one way of adding both a background image and foreground (overlay) geometry to the "normal" rendering:

// This example shows how to put a permanent background image on
// your viewer canvas, below the 3D graphics, plus overlay
// foreground geometry.  Written by mortene.
// Copyright Kongsberg Oil & Gas Technologies 2002.

// *************************************************************************

#include <Inventor/Qt/SoQt.h>
#include <Inventor/Qt/viewers/SoQtExaminerViewer.h>
#include <Inventor/nodes/SoBaseColor.h>
#include <Inventor/nodes/SoCone.h>
#include <Inventor/nodes/SoCube.h>
#include <Inventor/nodes/SoImage.h>
#include <Inventor/nodes/SoLightModel.h>
#include <Inventor/nodes/SoOrthographicCamera.h>
#include <Inventor/nodes/SoRotationXYZ.h>
#include <Inventor/nodes/SoSeparator.h>
#include <Inventor/nodes/SoTranslation.h>

#include <GL/gl.h>

// *************************************************************************

class MyExaminerViewer : public SoQtExaminerViewer {

public:
  MyExaminerViewer(QWidget* parent, const char * filename);
  ~MyExaminerViewer();

protected:
  virtual void actualRedraw(void);

private:
  SoSeparator * bckgroundroot;
  SoSeparator * foregroundroot;
  SoRotationXYZ * arrowrotation;
};

MyExaminerViewer::MyExaminerViewer(QWidget* parent, const char * filename)
  : SoQtExaminerViewer(parent)
{
  // Coin should not clear the pixel-buffer, so the background image
  // is not removed.
  this->setClearBeforeRender(FALSE, TRUE);


  // Set up background scenegraph with image in it.

  this->bckgroundroot = new SoSeparator;
  this->bckgroundroot->ref();

  SoOrthographicCamera * cam = new SoOrthographicCamera;
  cam->position = SbVec3f(0, 0, 1);
  cam->height = 1;
  // SoImage will be at z==0.0.
  cam->nearDistance = 0.5;
  cam->farDistance = 1.5;

  SoImage * img = new SoImage;
  img->vertAlignment = SoImage::HALF;
  img->horAlignment = SoImage::CENTER;
  img->filename = filename;

  this->bckgroundroot->addChild(cam);
  this->bckgroundroot->addChild(img);

  // Set up foreground, overlayed scenegraph.

  this->foregroundroot = new SoSeparator;
  this->foregroundroot->ref();

  SoLightModel * lm = new SoLightModel;
  lm->model = SoLightModel::BASE_COLOR;

  SoBaseColor * bc = new SoBaseColor;
  bc->rgb = SbColor(1, 1, 0);

  cam = new SoOrthographicCamera;
  cam->position = SbVec3f(0, 0, 5);
  cam->height = 10;
  cam->nearDistance = 0;
  cam->farDistance = 10;

  const double ARROWSIZE = 2.0;

  SoTranslation * posit = new SoTranslation;
  posit->translation = SbVec3f(-2.5 * ARROWSIZE, 1.5 * ARROWSIZE, 0);

  arrowrotation = new SoRotationXYZ;
  arrowrotation->axis = SoRotationXYZ::Z;

  SoTranslation * offset = new SoTranslation;
  offset->translation = SbVec3f(ARROWSIZE/2.0, 0, 0);

  SoCube * cube = new SoCube;
  cube->width = ARROWSIZE;
  cube->height = ARROWSIZE/15.0;

  this->foregroundroot->addChild(cam);
  this->foregroundroot->addChild(lm);
  this->foregroundroot->addChild(bc);
  this->foregroundroot->addChild(posit);
  this->foregroundroot->addChild(arrowrotation);
  this->foregroundroot->addChild(offset);
  this->foregroundroot->addChild(cube);
}

MyExaminerViewer::~MyExaminerViewer()
{
  this->bckgroundroot->unref();
  this->foregroundroot->unref();
}

void
MyExaminerViewer::actualRedraw(void)
{
  // Must set up the OpenGL viewport manually, as upon resize
  // operations, Coin won't set it up until the SoGLRenderAction is
  // applied again. And since we need to do glClear() before applying
  // the action..
  const SbViewportRegion vp = this->getViewportRegion();
  SbVec2s origin = vp.getViewportOriginPixels();
  SbVec2s size = vp.getViewportSizePixels();
  glViewport(origin[0], origin[1], size[0], size[1]);

  const SbColor col = this->getBackgroundColor();
  glClearColor(col[0], col[1], col[2], 0.0f);
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  // Render our scenegraph with the image.
  SoGLRenderAction * glra = this->getGLRenderAction();
  glra->apply(this->bckgroundroot);


  // Render normal scenegraph.
  SoQtExaminerViewer::actualRedraw();


  // Increase arrow angle with 1/1000 ° every frame.
  arrowrotation->angle = arrowrotation->angle.getValue() + (0.001 / M_PI * 180);
  // Render overlay front scenegraph.
  glClear(GL_DEPTH_BUFFER_BIT);
  glra->apply(this->foregroundroot);
}

// *************************************************************************

int
main(int argc, char ** argv)
{
  if (argc != 2) {
    (void)fprintf(stderr, "\n\n\tUsage: %s <image-filename>\n\n", argv[0]);
    exit(1);
  }

  QWidget* window = SoQt::init(argv[0]);

  MyExaminerViewer * viewer = new MyExaminerViewer(window, argv[1]);

  viewer->setSceneGraph(new SoCone);
  viewer->show();

  SoQt::show(window);
  SoQt::mainLoop();

  delete viewer;
  return 0;
}

// *************************************************************************

Reimplemented in SoQtViewer, SoQtExaminerViewer, SoQtFlyViewer, and SoQtPlaneViewer.

redrawOverlay()

void SoQtRenderArea::redrawOverlay ( void  )

protectedvirtual

This method redraws the overlay scene.

Reimplemented from SoQtGLWidget.

actualOverlayRedraw()

void SoQtRenderArea::actualOverlayRedraw ( void  )

protectedvirtual

This method renders the overlay scene.

processSoEvent()

SbBool SoQtRenderArea::processSoEvent ( const SoEvent *const  event )

protectedvirtual

Toolkit-native events are attempted converted to Coin-generic events in the SoQtRenderArea::processEvent() method. If this succeeds, they are forwarded to this method.

This is a virtual method, and is overridden in it's subclasses to catch events of particular interest to the viewer classes, for instance.

Return TRUE iff the event was processed. If not it should be passed on further up in the inheritance hierarchy by the caller. This last point is extremely important to take note of if you are expanding the toolkit with your own viewer class.

This method is not part of the original SGI InventorXt API. Note that you can still override the toolkit-native processEvent() method instead of this "generic" method.

Reimplemented in SoQtViewer, SoQtFullViewer, SoQtExaminerViewer, SoQtFlyViewer, and SoQtPlaneViewer.

processEvent()

void SoQtRenderArea::processEvent ( QEvent *  event )

protectedvirtual

Overrides SoQtGLWidget::processEvent() to attempt to convert toolkit-native events to Coin-generic events. If this succeeds, the generic SoEvent is forwarded to SoQtRenderArea::processSoEvent().

Reimplemented from SoQtGLWidget.

initGraphic()

void SoQtRenderArea::initGraphic ( void  )

protectedvirtual

This method is invoked to initialize the normal graphics.

Reimplemented from SoQtGLWidget.

initOverlayGraphic()

void SoQtRenderArea::initOverlayGraphic ( void  )

protectedvirtual

This method is invoked to initialize the overlay graphics.

Reimplemented from SoQtGLWidget.

sizeChanged()

void SoQtRenderArea::sizeChanged ( const SbVec2s &  size )

protectedvirtual

Called internally from within the SoQt library when the widget embedded in a component changes it size, which is usually triggered by end-user interaction.

This method is then invoked to notify the component that the size has changed. It is called from the top and all the way down to the bottom, the size being adjusted to take into account extra decorations having been added at each level in the component class hierarchy.

Reimplemented from SoQtGLWidget.

Reimplemented in SoQtViewer, and SoQtFullViewer.

widgetChanged()

void SoQtRenderArea::widgetChanged ( QWidget *  w )

protectedvirtual

This is the method which gets called whenever we change which OpenGL widget is used.

Should be overridden in subclasses which directly or indirectly store the return value from the SoQtGLWidget::getGLWidget() method.

See also

sizeChanged()

Reimplemented from SoQtGLWidget.

afterRealizeHook()

void SoQtRenderArea::afterRealizeHook ( void  )

protectedvirtual

A function "hook" / callback invoked just after the window for the component has been realized.

Override this if you need specific initialization for your own component or viewer class to happen right after it has been made visible, but remember to call upwards in the inheritance hierarchy:

void
MyLittleViewer::afterRealizeHook(void)
{
  <superclass>::afterRealizeHook();
  // [own initialization here]
}

Reimplemented from SoQtComponent.

Reimplemented in SoQtExaminerViewer, SoQtPlaneViewer, and SoQtFlyViewer.

getDefaultWidgetName()

const char * SoQtRenderArea::getDefaultWidgetName ( void  ) const

protectedvirtual

This method returns the default name of a component widget class.

It should be overridden by derived non-abstract classes for the topmost widget in the component to have a proper name.

Reimplemented from SoQtComponent.

Reimplemented in SoQtExaminerViewer, SoQtFlyViewer, and SoQtPlaneViewer.

getDefaultTitle()

const char * SoQtRenderArea::getDefaultTitle ( void  ) const

protectedvirtual

This method returns the default window caption string of the component.

It should be overridden by derived non-abstract classes so the window and popup menu will get a proper title.

Reimplemented from SoQtComponent.

Reimplemented in SoQtExaminerViewer, SoQtFlyViewer, and SoQtPlaneViewer.

getDefaultIconTitle()

const char * SoQtRenderArea::getDefaultIconTitle ( void  ) const

protectedvirtual

This method returns the default icon title of the component.

It should be overridden by derived non-abstract classes so icons will get proper titles.

Reimplemented from SoQtComponent.

Reimplemented in SoQtExaminerViewer, SoQtFlyViewer, and SoQtPlaneViewer.

glScheduleRedraw()

SbBool SoQtRenderArea::glScheduleRedraw ( void  )

protectedvirtual

Will be called whenever scene graph needs to be redrawn. If this method return FALSE, redraw() will be called immediately.

Default method simply returns FALSE. Override this method to schedule a redraw and return TRUE if you're trying to do The Right Thing.

Reimplemented from SoQtGLWidget.

---

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

• SoQtRenderArea.h
• SoQtRenderArea.cpp