javax.media.j3d
Class Canvas3D

java.lang.Object
  |
  +--java.awt.Component
        |
        +--java.awt.Canvas
              |
              +--javax.media.j3d.Canvas3D

public class Canvas3D

extends java.awt.Canvas

The Canvas3D class provides a drawing canvas for 3D rendering. It is used either for on-screen rendering or off-screen rendering. Canvas3D is an extension of the AWT Canvas class that users may further subclass to implement additional functionality.

The Canvas3D object extends the Canvas object to include 3D-related information such as the size of the canvas in pixels, the Canvas3D's location, also in pixels, within a Screen3D object, and whether or not the canvas has stereo enabled.

Because all Canvas3D objects contain a reference to a Screen3D object and because Screen3D objects define the size of a pixel in physical units, Java 3D can convert a Canvas3D size in pixels to a physical world size in meters. It can also determine the Canvas3D's position and orientation in the physical world.

On-screen Rendering vs. Off-screen Rendering

The Canvas3D class is used either for on-screen rendering or off-screen rendering. On-screen Canvas3Ds are added to AWT or Swing Container objects like any other canvas. Java 3D automatically and continuously renders to all on-screen canvases that are attached to an active View object. On-screen Canvas3Ds can be either single or double buffered and they can be either stereo or monoscopic.

Off-screen Canvas3Ds must not be added to any Container. Java 3D renders to off-screen canvases in response to the renderOffScreenBuffer method. Off-screen Canvas3Ds are single buffered. However, on many systems, the actual rendering is done to an off-screen hardware buffer or to a 3D library-specific buffer and only copied to the off-screen buffer of the Canvas when the rendering is complete, at "buffer swap" time. Off-screen Canvas3Ds are monoscopic.

The setOffScreenBuffer method sets the off-screen buffer for this Canvas3D. The specified image is written into by the Java 3D renderer. The size of the specified ImageComponent determines the size, in pixels, of this Canvas3D - the size inherited from Component is ignored. Note that the size, physical width, and physical height of the associated Screen3D must be set explicitly prior to rendering. Failure to do so will result in an exception.

The getOffScreenBuffer method retrieves the off-screen buffer for this Canvas3D.

The renderOffScreenBuffer method schedules the rendering of a frame into this Canvas3D's off-screen buffer. The rendering is done from the point of view of the View object to which this Canvas3D has been added. No rendering is performed if this Canvas3D object has not been added to an active View. This method does not wait for the rendering to actually happen. An application that wishes to know when the rendering is complete must either subclass Canvas3D and override the postSwap method, or call waitForOffScreenRendering.

The setOfScreenLocation methods set the location of this off-screen Canvas3D. The location is the upper-left corner of the Canvas3D relative to the upper-left corner of the corresponding off-screen Screen3D. The function of these methods is similar to that of Component.setLocation for on-screen Canvas3D objects. The default location is (0,0).

Accessing and Modifying an Eye's Image Plate Position

A Canvas3D object provides sophisticated applications with access to the eye's position information in head-tracked, room-mounted runtime environments. It also allows applications to manipulate the position of an eye relative to an image plate in non-head-tracked runtime environments.

The setLeftManualEyeInImagePlate and setRightManualEyeInImagePlate methods set the position of the manual left and right eyes in image plate coordinates. These values determine eye placement when a head tracker is not in use and the application is directly controlling the eye position in image plate coordinates. In head-tracked mode or when the windowEyepointPolicy is RELATIVE_TO_FIELD_OF_VIEW or RELATIVE_TO_COEXISTENCE, this value is ignored. When the windowEyepointPolicy is RELATIVE_TO_WINDOW, only the Z value is used.

The getLeftEyeInImagePlate, getRightEyeInImagePlate, and getCenterEyeInImagePlate methods retrieve the actual position of the left eye, right eye, and center eye in image plate coordinates and copy that value into the object provided. The center eye is the fictional eye half-way between the left and right eye. These three values are a function of the windowEyepointPolicy, the tracking enable flag, and the manual left, right, and center eye positions.

Monoscopic View Policy

The setMonoscopicViewPolicy and getMonoscopicViewPolicy methods set and retrieve the policy regarding how Java 3D generates monoscopic view. If the policy is set to View.LEFT_EYE_VIEW, the view generated corresponds to the view as seen from the left eye. If set to View.RIGHT_EYE_VIEW, the view generated corresponds to the view as seen from the right eye. If set to View.CYCLOPEAN_EYE_VIEW, the view generated corresponds to the view as seen from the "center eye," the fictional eye half-way between the left and right eye. The default monoscopic view policy is View.CYCLOPEAN_EYE_VIEW.

Immediate Mode Rendering

Pure immediate-mode rendering provides for those applications and applets that do not want Java 3D to do any automatic rendering of the scene graph. Such applications may not even wish to build a scene graph to represent their graphical data. However, they use Java 3D's attribute objects to set graphics state and Java 3D's geometric objects to render geometry.

A pure immediate mode application must create a minimal set of Java 3D objects before rendering. In addition to a Canvas3D object, the application must create a View object, with its associated PhysicalBody and PhysicalEnvironment objects, and the following scene graph elements: a VirtualUniverse object, a high-resolution Locale object, a BranchGroup node object, a TransformGroup node object with associated transform, and a ViewPlatform leaf node object that defines the position and orientation within the virtual universe that generates the view.

In immediate mode, all rendering is done completely under user control. It is necessary for the user to clear the 3D canvas, render all geometry, and swap the buffers. Additionally, rendering the right and left eye for stereo viewing becomes the sole responsibility of the application. In pure immediate mode, the user must stop the Java 3D renderer, via the Canvas3D object stopRenderer method, prior to adding the Canvas3D object to an active View object (that is, one that is attached to a live ViewPlatform object).

Other Canvas3D methods related to immediate mode rendering are:

getGraphicsContext3D retrieves the immediate-mode 3D graphics context associated with this Canvas3D. It creates a new graphics context if one does not already exist.

getGraphics2D retrieves the 2D graphics object associated with this Canvas3D. It creates a new 2D graphics object if one does not already exist.

preRender called by the Java 3D rendering loop after clearing the canvas and before any rendering has been done for this frame.

postRender called by the Java 3D rendering loop after completing all rendering to the canvas for this frame and before the buffer swap.

postSwap called by the Java 3D rendering loop after completing all rendering to the canvas, and all other canvases associated with this view, for this frame following the buffer swap.

renderField called by the Java 3D rendering loop during the execution of the rendering loop. It is called once for each field (i.e., once per frame on a mono system or once each for the right eye and left eye on a two-pass stereo system.

swap synchronizes and swaps buffers on a double-buffered canvas for this Canvas3D object. This method should only be called if the Java 3D renderer has been stopped. In the normal case, the renderer automatically swaps the buffer.

Mixed Mode Rendering

Mixing immediate mode and retained or compiled-retained mode requires more structure than pure immediate mode. In mixed mode, the Java 3D renderer is running continuously, rendering the scene graph into the canvas. The basic Java 3D stereo rendering loop, executed for each Canvas3D, is as follows:

 clear canvas (both eyes)
 call preRender()                           // user-supplied method
 set left eye view
 render opaque scene graph objects
 call renderField(FIELD_LEFT)               // user-supplied method
 render transparent scene graph objects
 set right eye view
 render opaque scene graph objects again
 call renderField(FIELD_RIGHT)              // user-supplied method
 render transparent scene graph objects again
 call postRender()                          // user-supplied method
 synchronize and swap buffers
 call postSwap()                            // user-supplied method
 

The basic Java 3D monoscopic rendering loop is as follows:

 clear canvas
 call preRender()                            // user-supplied method
 set view
 render opaque scene graph objects
 call renderField(FIELD_ALL)                 // user-supplied method
 render transparent scene graph objects
 call postRender()                           // user-supplied method
 synchronize and swap buffers
 call postSwap()                             // user-supplied method
 

In both cases, the entire loop, beginning with clearing the canvas and ending with swapping the buffers, defines a frame. The application is given the opportunity to render immediate-mode geometry at any of the clearly identified spots in the rendering loop. A user specifies his or her own rendering methods by extending the Canvas3D class and overriding the preRender, postRender, postSwap, and/or renderField methods.

See Also:

Screen3D, View, GraphicsContext3D, Serialized Form

Field Summary

static int	FIELD_ALL Specifies a single-field rendering loop.
static int	FIELD_LEFT Specifies the left field of a field-sequential stereo rendering loop.
static int	FIELD_RIGHT Specifies the right field of a field-sequential stereo rendering loop.

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Constructor Summary

Canvas3D(java.awt.GraphicsConfiguration graphicsConfiguration)
Constructs and initializes a new Canvas3D object that Java 3D can render into.

Canvas3D(java.awt.GraphicsConfiguration graphicsConfiguration, boolean offScreen)
Constructs and initializes a new Canvas3D object that Java 3D can render into.

Method Summary

void	addNotify() Canvas3D uses the addNotify callback to track when it is added to a container.
void	getCenterEyeInImagePlate(Point3d position) Retrieves the actual position of the center eye in image-plate coordinates and copies that value into the object provided.
boolean	getDoubleBufferAvailable() Returns a status flag indicating whether or not double buffering is available.
boolean	getDoubleBufferEnable() Returns a status flag indicating whether or not double buffering is enabled.
J3DGraphics2D	getGraphics2D() Get the 2D graphics object associated with this Canvas3D.
GraphicsContext3D	getGraphicsContext3D() Get the immediate mode 3D graphics context associated with this Canvas3D.
void	getImagePlateToVworld(Transform3D t) Retrieves the current ImagePlate coordinates to Virtual World coordinates transform and places it into the specified object.
void	getLeftEyeInImagePlate(Point3d position) Retrieves the actual position of the left eye in image-plate coordinates and copies that value into the object provided.
void	getLeftManualEyeInImagePlate(Point3d position) Retrieves the position of the user-specified, manual left eye in image-plate coordinates and copies that value into the object provided.
int	getMonoscopicViewPolicy() Returns policy on how Java 3D generates monoscopic view.
ImageComponent2D	getOffScreenBuffer() Retrieves the off-screen buffer for this Canvas3D.
java.awt.Point	getOffScreenLocation() Retrieves the location of this off-screen Canvas3D.
java.awt.Point	getOffScreenLocation(java.awt.Point rv) Retrieves the location of this off-screen Canvas3D and stores it in the specified Point object.
double	getPhysicalHeight() Retrieves the physical height of this canvas window in meters.
double	getPhysicalWidth() Retrieves the physical width of this canvas window in meters.
void	getPixelLocationFromImagePlate(Point3d imagePlatePoint, Point2d pixelLocation) Projects the specified point from image plate coordinates into AWT pixel coordinates.
void	getPixelLocationInImagePlate(int x, int y, Point3d imagePlatePoint) Computes the position of the specified AWT pixel value in image-plate coordinates and copies that value into the object provided.
void	getPixelLocationInImagePlate(Point2d pixelLocation, Point3d imagePlatePoint) Computes the position of the specified AWT pixel value in image-plate coordinates and copies that value into the object provided.
void	getRightEyeInImagePlate(Point3d position) Retrieves the actual position of the right eye in image-plate coordinates and copies that value into the object provided.
void	getRightManualEyeInImagePlate(Point3d position) Retrieves the position of the user-specified, manual right eye in image-plate coordinates and copies that value into the object provided.
boolean	getSceneAntialiasingAvailable() Returns a status flag indicating whether or not scene antialiasing is available.
Screen3D	getScreen3D() Retrieve the Screen3D object that this Canvas3D is attached to.
java.awt.Dimension	getSize()
boolean	getStereoAvailable() Returns a status flag indicating whether or not stereo is available.
boolean	getStereoEnable() Returns a status flag indicating whether or not stereo is enabled.
View	getView() Gets view that points to this Canvas3D.
void	getVworldToImagePlate(Transform3D t) Retrieves the current Virtual World coordinates to ImagePlate coordinates transform and places it into the specified object.
boolean	isOffScreen() Retrieves a flag indicating whether this Canvas3D is an off-screen canvas.
boolean	isRendererRunning() Retrieves the state of the renderer for this Canvas3D object.
void	paint(java.awt.Graphics g) Canvas3D uses the paint callback to track when it is possible to render into the canvas.
void	postRender() This routine is called by the Java 3D rendering loop after completing all rendering to the canvas for this frame and before the buffer swap.
void	postSwap() This routine is called by the Java 3D rendering loop after completing all rendering to the canvas, and all other canvases associated with this view, for this frame following the buffer swap.
void	preRender() This routine is called by the Java 3D rendering loop after clearing the canvas and before any rendering has been done for this frame.
java.util.Map	queryProperties() Returns a read-only Map object containing key-value pairs that define various properties for this Canvas3D.
void	removeNotify() Canvas3D uses the removeNotify callback to track when it is removed from a container.
void	renderField(int fieldDesc) This routine is called by the Java 3D rendering loop during the execution of the rendering loop.
void	renderOffScreenBuffer() Schedules the rendering of a frame into this Canvas3D's off-screen buffer.
void	setDoubleBufferEnable(boolean flag) Turns double buffering on or off.
void	setLeftManualEyeInImagePlate(Point3d position) Sets the position of the manual left eye in image-plate coordinates.
void	setMonoscopicViewPolicy(int policy) Specifies how Java 3D generates monoscopic view.
void	setOffScreenBuffer(ImageComponent2D buffer) Sets the off-screen buffer for this Canvas3D.
void	setOffScreenLocation(int x, int y) Sets the location of this off-screen Canvas3D.
void	setOffScreenLocation(java.awt.Point p) Sets the location of this off-screen Canvas3D.
void	setRightManualEyeInImagePlate(Point3d position) Sets the position of the manual right eye in image-plate coordinates.
void	setStereoEnable(boolean flag) Turns stereo on or off.
void	startRenderer() Start the Java 3D renderer on this Canvas3D object.
void	stopRenderer() Stop the Java 3D renderer on this Canvas3D object.
void	swap() Synchronize and swap buffers on a double buffered canvas for this Canvas3D object.
void	waitForOffScreenRendering() Waits for this Canvas3D's off-screen rendering to be done.

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addPropertyChangeListener, addPropertyChangeListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, deliverEvent, disable, disableEvents, dispatchEvent, doLayout, enable, enable, enableEvents, enableInputMethods, firePropertyChange, getAlignmentX, getAlignmentY, getBackground, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentOrientation, getCursor, getDropTarget, getFont, getFontMetrics, getForeground, getGraphics, getHeight, getInputContext, getInputMethodRequests, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMinimumSize, getName, getParent, getPeer, getPreferredSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, invalidate, isDisplayable, isDoubleBuffered, isEnabled, isFocusTraversable, isLightweight, isOpaque, isShowing, isValid, isVisible, keyDown, keyUp, layout, list, list, list, list, list, locate, location, lostFocus, minimumSize, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, paramString, postEvent, preferredSize, prepareImage, prepareImage, print, printAll, processComponentEvent, processEvent, processFocusEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, remove, removeComponentListener, removeFocusListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, reshape, resize, resize, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFont, setForeground, setLocale, setLocation, setLocation, setName, setSize, setSize, setVisible, show, show, size, toString, transferFocus, update, validate

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

FIELD_LEFT

public static final int FIELD_LEFT

Specifies the left field of a field-sequential stereo rendering loop. A left field always precedes a right field.

FIELD_RIGHT

public static final int FIELD_RIGHT

Specifies the right field of a field-sequential stereo rendering loop. A right field always follows a left field.

FIELD_ALL

public static final int FIELD_ALL

Specifies a single-field rendering loop.

Constructor Detail

Canvas3D

public Canvas3D(java.awt.GraphicsConfiguration graphicsConfiguration)

Constructs and initializes a new Canvas3D object that Java 3D can render into. The following Canvas3D attributes are initialized to default values as shown:

left manual eye in image plate : (0.142, 0.135, 0.4572)
right manual eye in image plate : (0.208, 0.135, 0.4572)
stereo enable : true
double buffer enable : true
monoscopic view policy : View.CYCLOPEAN_EYE_VIEW
off-screen mode : false
off-screen buffer : null
off-screen location : (0,0)

Parameters:

graphicsConfiguration - a valid GraphicsConfiguration object that will be used to create the canvas. This object should not be null. For backward compatibility with earlier versions of Java 3D, a null GraphicsConfiguration will still work when used to create a Canvas3D on the default screen, but a warning message will be printed.

Canvas3D

public Canvas3D(java.awt.GraphicsConfiguration graphicsConfiguration,
                boolean offScreen)

Constructs and initializes a new Canvas3D object that Java 3D can render into.

Parameters:

graphicsConfiguration - a valid GraphicsConfiguration object that will be used to create the canvas.

offScreen - a flag that indicates whether this canvas is an off-screen 3D rendering canvas. Note that if offScreen is set to true, this Canvas3D object cannot be used for normal rendering; it should not be added to any Container object.

Throws:

NullPointerException - if the GraphicsConfiguration is null.

Since:

Java 3D 1.2

Method Detail

paint

public void paint(java.awt.Graphics g)

Canvas3D uses the paint callback to track when it is possible to render into the canvas. Subclasses of Canvas3D that override this method need to call super.paint() in their paint method for Java 3D to function properly.

Overrides:

paint in class java.awt.Canvas

Parameters:

g - the graphics context

addNotify

public void addNotify()

Canvas3D uses the addNotify callback to track when it is added to a container. Subclasses of Canvas3D that override this method need to call super.addNotify() in their addNotify() method for Java 3D to function properly.

Overrides:

addNotify in class java.awt.Canvas

removeNotify

public void removeNotify()

Canvas3D uses the removeNotify callback to track when it is removed from a container. Subclasses of Canvas3D that override this method need to call super.removeNotify() in their removeNotify() method for Java 3D to function properly.

Overrides:

removeNotify in class java.awt.Component

getScreen3D

public Screen3D getScreen3D()

Retrieve the Screen3D object that this Canvas3D is attached to. If this Canvas3D is an off-screen buffer, a new Screen3D object is created corresponding to the off-screen buffer.

Returns:

the 3D screen object that this Canvas3D is attached to

getGraphicsContext3D

public GraphicsContext3D getGraphicsContext3D()

Get the immediate mode 3D graphics context associated with this Canvas3D. A new graphics context object is created if one does not already exist.

Returns:

a GraphicsContext3D object that can be used for immediate mode rendering to this Canvas3D.

getGraphics2D

public J3DGraphics2D getGraphics2D()

Get the 2D graphics object associated with this Canvas3D. A new 2D graphics object is created if one does not already exist.

Returns:

a Graphics2D object that can be used for Java 2D rendering into this Canvas3D.

Since:

Java 3D 1.2

preRender

public void preRender()

This routine is called by the Java 3D rendering loop after clearing the canvas and before any rendering has been done for this frame. Applications that wish to perform operations in the rendering loop, prior to any actual rendering may override this function.
NOTE: Applications should not call this method.

postRender

public void postRender()

This routine is called by the Java 3D rendering loop after completing all rendering to the canvas for this frame and before the buffer swap. Applications that wish to perform operations in the rendering loop, following any actual rendering may override this function.
NOTE: Applications should not call this method.

postSwap

public void postSwap()

This routine is called by the Java 3D rendering loop after completing all rendering to the canvas, and all other canvases associated with this view, for this frame following the buffer swap. Applications that wish to perform operations at the very end of the rendering loop may override this function. In off-screen mode, all rendering is copied to the off-screen buffer before this method is called.
NOTE: Applications should not call this method.

renderField

public void renderField(int fieldDesc)

This routine is called by the Java 3D rendering loop during the execution of the rendering loop. It is called once for each field (i.e., once per frame on a mono system or once each for the right eye and left eye on a two-pass stereo system. This is intended for use by applications that want to mix retained/compiled-retained mode rendering with some immediate mode rendering. Applications that wish to perform operations during the rendering loop, may override this function.
NOTE: Applications should not call this method.

Parameters:

fieldDesc - field description, one of: FIELD_LEFT, FIELD_RIGHT or FIELD_ALL. Applications that wish to work correctly in stereo mode should render the same image for both FIELD_LEFT and FIELD_RIGHT calls. If Java 3D calls the renderer with FIELD_ALL then the immediate mode rendering only needs to be done once.

stopRenderer

public final void stopRenderer()

Stop the Java 3D renderer on this Canvas3D object. If the Java 3D renderer is currently running, the rendering will be synchronized before being stopped. No further rendering will be done to this canvas by Java 3D until the renderer is started again. In pure immediate mode this method should be called prior to adding this canvas to an active View object.

Throws:

java.lang.IllegalStateException - if this Canvas3D is in off-screen mode.

startRenderer

public final void startRenderer()

Start the Java 3D renderer on this Canvas3D object. If the Java 3D renderer is not currently running, any rendering to other Canvas3D objects sharing the same View will be synchronized before this Canvas3D's renderer is (re)started. When a Canvas3D is created, it is initially marked as being started. This means that as soon as the Canvas3D is added to an active View object, the rendering loop will render the scene graph to the canvas.

isRendererRunning

public final boolean isRendererRunning()

Retrieves the state of the renderer for this Canvas3D object.

Returns:

the state of the renderer

Since:

Java 3D 1.2

isOffScreen

public boolean isOffScreen()

Retrieves a flag indicating whether this Canvas3D is an off-screen canvas.

Returns:

true if this Canvas3D is an off-screen canvas; false if this is an on-screen canvas.

Since:

Java 3D 1.2

setOffScreenBuffer

public void setOffScreenBuffer(ImageComponent2D buffer)

Sets the off-screen buffer for this Canvas3D. The specified image is written into by the Java 3D renderer. The size of the specified ImageComponent determines the size, in pixels, of this Canvas3D--the size inherited from Component is ignored.
NOTE: the size, physical width, and physical height of the associated Screen3D must be set explicitly prior to rendering. Failure to do so will result in an exception.

Parameters:

buffer - the image component that will be rendered into by subsequent calls to renderOffScreenBuffer.

Throws:

java.lang.IllegalStateException - if this Canvas3D is not in off-screen mode.

RestrictedAccessException - if an off-screen rendering is in process for this Canvas3D.

IllegalSharingException - if the specified ImageComponent2D is used by more than one Canvas3D.

java.lang.IllegalArgumentException - if the specified ImageComponent2D is in by-reference mode and its RenderedImage is not an instance of a BufferedImage.

Since:

Java 3D 1.2

See Also:

renderOffScreenBuffer(), Screen3D.setSize(int, int), Screen3D.setSize(Dimension), Screen3D.setPhysicalScreenWidth(double), Screen3D.setPhysicalScreenHeight(double)

getOffScreenBuffer

public ImageComponent2D getOffScreenBuffer()

Retrieves the off-screen buffer for this Canvas3D.

Returns:

the current off-screen buffer for this Canvas3D.

Throws:

java.lang.IllegalStateException - if this Canvas3D is not in off-screen mode.

Since:

Java 3D 1.2

renderOffScreenBuffer

public void renderOffScreenBuffer()

Schedules the rendering of a frame into this Canvas3D's off-screen buffer. The rendering is done from the point of view of the View object to which this Canvas3D has been added. No rendering is performed if this Canvas3D object has not been added to an active View. This method does not wait for the rendering to actually happen. An application that wishes to know when the rendering is complete must either subclass Canvas3D and override the postSwap method, or call waitForOffScreenRendering.

Throws:

NullPointerException - if the off-screen buffer is null.

java.lang.IllegalStateException - if this Canvas3D is not in off-screen mode, or if either the width or the height of the associated Screen3D's size is <= 0, or if the associated Screen3D's physical width or height is <= 0.

RestrictedAccessException - if an off-screen rendering is already in process for this Canvas3D or if the Java 3D renderer is stopped.

Since:

Java 3D 1.2

See Also:

setOffScreenBuffer(javax.media.j3d.ImageComponent2D), Screen3D.setSize(int, int), Screen3D.setSize(Dimension), Screen3D.setPhysicalScreenWidth(double), Screen3D.setPhysicalScreenHeight(double), waitForOffScreenRendering(), postSwap()

waitForOffScreenRendering

public void waitForOffScreenRendering()

Waits for this Canvas3D's off-screen rendering to be done. This method will wait until the postSwap method of this off-screen Canvas3D has completed. If this Canvas3D has not been added to an active view or if the renderer is stopped for this Canvas3D, then this method will return immediately. This method must not be called from a render callback method of an off-screen Canvas3D.

Throws:

java.lang.IllegalStateException - if this Canvas3D is not in off-screen mode, or if this method is called from a render callback method of an off-screen Canvas3D.

Since:

Java 3D 1.2

See Also:

renderOffScreenBuffer(), postSwap()

setOffScreenLocation

public void setOffScreenLocation(int x,
                                 int y)

Sets the location of this off-screen Canvas3D. The location is the upper-left corner of the Canvas3D relative to the upper-left corner of the corresponding off-screen Screen3D. The function of this method is similar to that of Component.setLocation for on-screen Canvas3D objects. The default location is (0,0).

Parameters:

x - the x coordinate of the upper-left corner of the new location.

y - the y coordinate of the upper-left corner of the new location.

Throws:

java.lang.IllegalStateException - if this Canvas3D is not in off-screen mode.

Since:

Java 3D 1.2

setOffScreenLocation

public void setOffScreenLocation(java.awt.Point p)

Sets the location of this off-screen Canvas3D. The location is the upper-left corner of the Canvas3D relative to the upper-left corner of the corresponding off-screen Screen3D. The function of this method is similar to that of Component.setLocation for on-screen Canvas3D objects. The default location is (0,0).

Parameters:

p - the point defining the upper-left corner of the new location.

Throws:

java.lang.IllegalStateException - if this Canvas3D is not in off-screen mode.

Since:

Java 3D 1.2

getOffScreenLocation

public java.awt.Point getOffScreenLocation()

Retrieves the location of this off-screen Canvas3D. The location is the upper-left corner of the Canvas3D relative to the upper-left corner of the corresponding off-screen Screen3D. The function of this method is similar to that of Component.getLocation for on-screen Canvas3D objects.

Returns:

a new point representing the upper-left corner of the location of this off-screen Canvas3D.

Throws:

java.lang.IllegalStateException - if this Canvas3D is not in off-screen mode.

Since:

Java 3D 1.2

getOffScreenLocation

public java.awt.Point getOffScreenLocation(java.awt.Point rv)

Retrieves the location of this off-screen Canvas3D and stores it in the specified Point object. The location is the upper-left corner of the Canvas3D relative to the upper-left corner of the corresponding off-screen Screen3D. The function of this method is similar to that of Component.getLocation for on-screen Canvas3D objects. This version of getOffScreenLocation is useful if the caller wants to avoid allocating a new Point object on the heap.

Parameters:

rv - Point object into which the upper-left corner of the location of this off-screen Canvas3D is copied. If rv is null, a new Point is allocated.

Returns:

rv

Throws:

java.lang.IllegalStateException - if this Canvas3D is not in off-screen mode.

Since:

Java 3D 1.2

swap

public void swap()

Synchronize and swap buffers on a double buffered canvas for this Canvas3D object. This method should only be called if the Java 3D renderer has been stopped. In the normal case, the renderer automatically swaps the buffer. This method calls the flush(true) methods of the associated 2D and 3D graphics contexts, if they have been allocated.

Throws:

RestrictedAccessException - if the Java 3D renderer is running.

java.lang.IllegalStateException - if this Canvas3D is in off-screen mode.

See Also:

stopRenderer(), GraphicsContext3D.flush(boolean), J3DGraphics2D.flush(boolean)

setLeftManualEyeInImagePlate

public void setLeftManualEyeInImagePlate(Point3d position)

Sets the position of the manual left eye in image-plate coordinates. This value determines eye placement when a head tracker is not in use and the application is directly controlling the eye position in image-plate coordinates. In head-tracked mode or when the windowEyePointPolicy is RELATIVE_TO_FIELD_OF_VIEW or RELATIVE_TO_COEXISTENCE, this value is ignored. When the windowEyepointPolicy is RELATIVE_TO_WINDOW only the Z value is used.

Parameters:

position - the new manual left eye position

setRightManualEyeInImagePlate

public void setRightManualEyeInImagePlate(Point3d position)

Sets the position of the manual right eye in image-plate coordinates. This value determines eye placement when a head tracker is not in use and the application is directly controlling the eye position in image-plate coordinates. In head-tracked mode or when the windowEyePointPolicy is RELATIVE_TO_FIELD_OF_VIEW or RELATIVE_TO_COEXISTENCE, this value is ignored. When the windowEyepointPolicy is RELATIVE_TO_WINDOW only the Z value is used.

Parameters:

position - the new manual right eye position

getLeftManualEyeInImagePlate

public void getLeftManualEyeInImagePlate(Point3d position)

Retrieves the position of the user-specified, manual left eye in image-plate coordinates and copies that value into the object provided.

Parameters:

position - the object that will receive the position

getRightManualEyeInImagePlate

public void getRightManualEyeInImagePlate(Point3d position)

Retrieves the position of the user-specified, manual right eye in image-plate coordinates and copies that value into the object provided.

Parameters:

position - the object that will receive the position

getLeftEyeInImagePlate

public void getLeftEyeInImagePlate(Point3d position)

Retrieves the actual position of the left eye in image-plate coordinates and copies that value into the object provided. This value is a function of the windowEyepointPolicy, the tracking enable flag, and the manual left eye position.

Parameters:

position - the object that will receive the position

getRightEyeInImagePlate

public void getRightEyeInImagePlate(Point3d position)

Retrieves the actual position of the right eye in image-plate coordinates and copies that value into the object provided. This value is a function of the windowEyepointPolicy, the tracking enable flag, and the manual right eye position.

Parameters:

position - the object that will receive the position

getCenterEyeInImagePlate

public void getCenterEyeInImagePlate(Point3d position)

Retrieves the actual position of the center eye in image-plate coordinates and copies that value into the object provided. The center eye is the fictional eye half-way between the left and right eye. This value is a function of the windowEyepointPolicy, the tracking enable flag, and the manual right and left eye positions.

Parameters:

position - the object that will receive the position

See Also:

setMonoscopicViewPolicy(int)

getImagePlateToVworld

public void getImagePlateToVworld(Transform3D t)

Retrieves the current ImagePlate coordinates to Virtual World coordinates transform and places it into the specified object.

Parameters:

t - the Transform3D object that will receive the transform

getPixelLocationInImagePlate

public void getPixelLocationInImagePlate(int x,
                                         int y,
                                         Point3d imagePlatePoint)

Computes the position of the specified AWT pixel value in image-plate coordinates and copies that value into the object provided.

Parameters:

x - the X coordinate of the pixel relative to the upper-left hand corner of the window.

y - the Y coordinate of the pixel relative to the upper-left hand corner of the window.

imagePlatePoint - the object that will receive the position in physical image plate coordinates (relative to the lower-left corner of the screen).

getPixelLocationInImagePlate

public void getPixelLocationInImagePlate(Point2d pixelLocation,
                                         Point3d imagePlatePoint)

Computes the position of the specified AWT pixel value in image-plate coordinates and copies that value into the object provided.

Parameters:

pixelLocation - the coordinates of the pixel relative to the upper-left hand corner of the window.

imagePlatePoint - the object that will receive the position in physical image plate coordinates (relative to the lower-left corner of the screen).

Since:

Java 3D 1.2

getPixelLocationFromImagePlate

public void getPixelLocationFromImagePlate(Point3d imagePlatePoint,
                                           Point2d pixelLocation)

Projects the specified point from image plate coordinates into AWT pixel coordinates. The AWT pixel coordinates are copied into the object provided.

Parameters:

imagePlatePoint - the position in physical image plate coordinates (relative to the lower-left corner of the screen).

pixelLocation - the object that will receive the coordinates of the pixel relative to the upper-left hand corner of the window.

Since:

Java 3D 1.2

getPhysicalWidth

public double getPhysicalWidth()

Retrieves the physical width of this canvas window in meters.

Returns:

the physical window width in meters.

getPhysicalHeight

public double getPhysicalHeight()

Retrieves the physical height of this canvas window in meters.

Returns:

the physical window height in meters.

getVworldToImagePlate

public void getVworldToImagePlate(Transform3D t)

Retrieves the current Virtual World coordinates to ImagePlate coordinates transform and places it into the specified object.

Parameters:

t - the Transform3D object that will receive the transform

getView

public View getView()

Gets view that points to this Canvas3D.

Returns:

view object that points to this Canvas3D

getStereoAvailable

public boolean getStereoAvailable()

Returns a status flag indicating whether or not stereo is available. This is equivalent to:

((Boolean)queryProperties(). get("stereoAvailable")). booleanValue()

Returns:

a flag indicating whether stereo is available

setStereoEnable

public void setStereoEnable(boolean flag)

Turns stereo on or off. Note that this attribute is used only when stereo is available. Enabling stereo on a Canvas3D that does not support stereo has no effect.

Parameters:

flag - enables or disables the display of stereo

See Also:

queryProperties()

getStereoEnable

public boolean getStereoEnable()

Returns a status flag indicating whether or not stereo is enabled.

Returns:

a flag indicating whether stereo is enabled

setMonoscopicViewPolicy

public void setMonoscopicViewPolicy(int policy)

Specifies how Java 3D generates monoscopic view. If set to View.LEFT_EYE_VIEW, the view generated corresponds to the view as seen from the left eye. If set to View.RIGHT_EYE_VIEW, the view generated corresponds to the view as seen from the right eye. If set to View.CYCLOPEAN_EYE_VIEW, the view generated corresponds to the view as seen from the 'center eye', the fictional eye half-way between the left and right eye. The default monoscopic view policy is View.CYCLOPEAN_EYE_VIEW.

NOTE: for backward compatibility with Java 3D 1.1, if this attribute is set to its default value of View.CYCLOPEAN_EYE_VIEW, the monoscopic view policy in the View object will be used. An application should not use both the deprecated View method and this Canvas3D method at the same time.

Parameters:

policy - one of View.LEFT_EYE_VIEW, View.RIGHT_EYE_VIEW, or View.CYCLOPEAN_EYE_VIEW.

Throws:

java.lang.IllegalStateException - if the specified policy is CYCLOPEAN_EYE_VIEW, the canvas is a stereo canvas, and the viewPolicy for the associated view is HMD_VIEW

Since:

Java 3D 1.2

getMonoscopicViewPolicy

public int getMonoscopicViewPolicy()

Returns policy on how Java 3D generates monoscopic view.

Returns:

policy one of View.LEFT_EYE_VIEW, View.RIGHT_EYE_VIEW or View.CYCLOPEAN_EYE_VIEW.

Since:

Java 3D 1.2

getDoubleBufferAvailable

public boolean getDoubleBufferAvailable()

Returns a status flag indicating whether or not double buffering is available. This is equivalent to:

((Boolean)queryProperties(). get("doubleBufferAvailable")). booleanValue()

Returns:

a flag indicating whether double buffering is available.

setDoubleBufferEnable

public void setDoubleBufferEnable(boolean flag)

Turns double buffering on or off. If double buffering is off, all drawing is to the front buffer and no buffer swap is done between frames. It should be stressed that running Java 3D with double buffering disabled is not recommended. Enabling double buffering on a Canvas3D that does not support double buffering has no effect.

Parameters:

flag - enables or disables double buffering.

See Also:

queryProperties()

getDoubleBufferEnable

public boolean getDoubleBufferEnable()

Returns a status flag indicating whether or not double buffering is enabled.

Returns:

a flag indicating if double buffering is enabled.

getSceneAntialiasingAvailable

public boolean getSceneAntialiasingAvailable()

Returns a status flag indicating whether or not scene antialiasing is available. This is equivalent to:

((Boolean)queryProperties(). get("sceneAntialiasingAvailable")). booleanValue()

Returns:

a flag indicating whether scene antialiasing is available.

queryProperties

public final java.util.Map queryProperties()

Returns a read-only Map object containing key-value pairs that define various properties for this Canvas3D. All of the keys are String objects. The values are key-specific, but most will be Boolean, Integer, Double, or String objects.

The currently defined keys are:

Key (String)	Value Type
doubleBufferAvailable	Boolean
stereoAvailable	Boolean
sceneAntialiasingAvailable	Boolean
texture3DAvailable	Boolean
textureColorTableSize	Integer
compressedGeometry.majorVersionNumber	Integer
compressedGeometry.minorVersionNumber	Integer
compressedGeometry.minorMinorVersionNumber	Integer

The descriptions of the values returned for each key are as follows:

• doubleBufferAvailable
  A Boolean indicating whether or not double buffering is available for this Canvas3D. This is equivalent to the getDoubleBufferAvailable method. If this flag is false, the Canvas3D will be rendered in single buffer mode; requests to enable double buffering will be ignored.
• stereoAvailable
  A Boolean indicating whether or not stereo is available for this Canvas3D. This is equivalent to the getStereoAvailable method. If this flag is false, the Canvas3D will be rendered in monoscopic mode; requests to enable stereo will be ignored.
• sceneAntialiasingAvailable
  A Boolean indicating whether or not scene antialiasing is available for this Canvas3D. This is equivalent to the getSceneAntialiasingAvailable method. If this flag is false, requests to enable scene antialiasing will be ignored.
• texture3DAvailable
  A Boolean indicating whether or not 3D Texture mapping is available for this Canvas3D. If this flag is false, 3D texture mapping is either not supported by the underlying rendering layer or is otherwise unavailable for this particular Canvas3D. All use of 3D texture mapping will be ignored in this case.
• textureColorTableSize
  An Integer indicating the maximum size of the texture color table for this Canvas3D. If the size is 0, the texture color table is either not supported by the underlying rendering layer or is otherwise unavailable for this particular Canvas3D. An attempt to use a texture color table larger than textureColorTableSize will be ignored; no color lookup will be performed.
• compressedGeometry.majorVersionNumber
compressedGeometry.minorVersionNumber
compressedGeometry.minorMinorVersionNumber
  Integers indicating the major, minor, and minor-minor version numbers, respectively, of the version of compressed geometry supported by this version of Java 3D.

Returns:

the properties of this Canavs3D

Since:

Java 3D 1.2

getSize

public java.awt.Dimension getSize()

Overrides:

getSize in class java.awt.Component