de.javagl.viewer

Class Viewer

java.lang.Object

java.awt.Component

java.awt.Container

javax.swing.JComponent

javax.swing.JPanel

de.javagl.viewer.Viewer

All Implemented Interfaces:

java.awt.image.ImageObserver, java.awt.MenuContainer, java.io.Serializable, javax.accessibility.Accessible

public class Viewer
extends javax.swing.JPanel

A panel that allows translating, rotating and zooming.

Instances of classes implementing the Painter interface may be added to this viewer and perform painting operations. Their paint method will receive the world-to-screen transform, as determined by the current translation, rotation and zoom of the viewer.

The viewer supports multiple layers. The layer may be specified when a Painter is added using the addPainter(Painter, int) method. The Painter instances will be called starting at the lowest layer. Inside one layer, the Painters will be called in the order in which they have been added.

A viewer has several methods that affect the translation, rotation and zoom factor:

• translate(double, double)
• rotate(double, double, double)
• zoom(double, double, double, double)

These methods will usually not be called by clients or users of the viewer. Instead, they are called by a class that implements the MouseControl interface, and has been set using setMouseControl(MouseControl). These classes are responsible for making sure that these methods are called with valid parameters. Particularly, they should not be called with NaN or infinite values, and the zooming factors should not be 0.0. The viewer class itself does not perform any sanity checks on these arguments.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class javax.swing.JPanel

javax.swing.JPanel.AccessibleJPanel

Nested classes/interfaces inherited from class javax.swing.JComponent

javax.swing.JComponent.AccessibleJComponent

Nested classes/interfaces inherited from class java.awt.Container

java.awt.Container.AccessibleAWTContainer

Nested classes/interfaces inherited from class java.awt.Component

java.awt.Component.AccessibleAWTComponent, java.awt.Component.BaselineResizeBehavior, java.awt.Component.BltBufferStrategy, java.awt.Component.FlipBufferStrategy

Field Summary

Fields inherited from class javax.swing.JComponent

listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW

Fields inherited from class java.awt.Component

accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

Constructors

Constructor and Description
Viewer() Creates a new Viewer.

Method Summary

Modifier and Type	Method and Description
boolean	addPainter(Painter painter) Add the given Painter, which will perform painting operations in the paintComponent(Graphics) method.
boolean	addPainter(Painter painter, int layer) Add the given Painter, which will perform painting operations in the paintComponent(Graphics) method, on the specified layer.
java.awt.geom.AffineTransform	getScreenToWorld() Returns a copy of the screen-to-world transform
java.awt.geom.AffineTransform	getWorldToScreen() Returns a copy of the current world-to-screen transform
boolean	isAntialiasing() Return whether the antialiasing rendering hint is enabled by default
boolean	isFlippedVertically() Set whether the y-axis is flipped to point from the bottom of the screen to the top
boolean	isMaintainAspectRatio() Returns whether the aspect ratio is maintained during resize operations or when setDisplayedWorldArea(Rectangle2D) is called
boolean	isResizingContents() Returns whether this viewer is configured so that the contents should be resized when the screen is resized.
protected void	paintComponent(java.awt.Graphics gr)
boolean	removePainter(Painter painter) Remove the given Painter from all layers that it is contained in
boolean	removePainter(Painter painter, int layer) Remove the given Painter from the specified layer
void	resetTransform() Reset this viewer to the identity transform
void	rotate(double screenCenterX, double screenCenterY, double angleRad) Rotate about the specified point (in screen coordinates) by the given angle (in radians)
void	setAntialiasing(boolean antialiasing) Set whether the antialiasing rendering hint should be enabled by default
void	setDisplayedWorldArea(double x, double y, double w, double h) Set the area (in world coordinates) that should be shown.
void	setDisplayedWorldArea(java.awt.geom.Rectangle2D newWorldArea) Set the area (in world coordinates) that should be shown.
void	setFlippedVertically(boolean flippedVertically) Set whether the y-axis should be flipped to point from the bottom of the screen to the top
void	setMaintainAspectRatio(boolean maintainAspectRatio) Set whether the aspect ratio of the displayed world area is maintained during resize operations of this panel, or when setDisplayedWorldArea(Rectangle2D) is called.
void	setMouseControl(MouseControl newMouseControl) Set the given MouseControl as a MouseListener, MouseMotionListener and MouseWheelListener for this viewer.
void	setResizingContents(boolean resizingContents) Set whether the contents should be resized when the screen is resized.
void	setTransform(java.awt.geom.AffineTransform t) Set the world-to-screen transform of this viewer to the given transform.
void	transform(java.awt.geom.AffineTransform t) Transform the contents of this viewer with the given transform
void	translate(double screenDx, double screenDy) Translate this viewer by the given delta, in screen coordinates
void	zoom(double screenCenterX, double screenCenterY, double factorX, double factorY) Zoom about the specified point (in screen coordinates) by the given factor.

Methods inherited from class javax.swing.JPanel

getAccessibleContext, getUI, getUIClassID, paramString, setUI, updateUI

Methods inherited from class javax.swing.JComponent

addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paint, paintBorder, paintChildren, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTree

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods inherited from class java.lang.Object

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

Constructor Detail

Viewer

public Viewer()

Creates a new Viewer.

The default settings are as follows:

• isResizingContents() is false
• isMaintainAspectRatio() is true
• isAntialiasing() is true

A default MouseControl, where rotation and non-uniform scaling are allowed, will be installed by calling setMouseControl(MouseControl)

Method Detail

setMouseControl

public final void setMouseControl(MouseControl newMouseControl)

Set the given MouseControl as a MouseListener, MouseMotionListener and MouseWheelListener for this viewer. Any previously registered MouseControl will be removed.

Parameters:

newMouseControl - The MouseControl to set. This may be null to remove any MouseControl

setFlippedVertically

public final void setFlippedVertically(boolean flippedVertically)

Set whether the y-axis should be flipped to point from the bottom of the screen to the top

Parameters:

flippedVertically - Whether the y-axis should be flipped

isFlippedVertically

public final boolean isFlippedVertically()

Set whether the y-axis is flipped to point from the bottom of the screen to the top

Returns:

Whether the y-axis is be flipped

setResizingContents

public final void setResizingContents(boolean resizingContents)

Set whether the contents should be resized when the screen is resized. When this is set to true, then resizing this panel will adjust the scale factors accordingly, so that the world area that is displayed remains the same while resizing.

Note that this usually only makes sense when the aspect ratio is not maintained - that is, when setMaintainAspectRatio(boolean) was set to false.

Parameters:

resizingContents - The resizing behavior

isResizingContents

public final boolean isResizingContents()

Returns whether this viewer is configured so that the contents should be resized when the screen is resized. See setResizingContents(boolean).

Returns:

The resizing behavior

setMaintainAspectRatio

public final void setMaintainAspectRatio(boolean maintainAspectRatio)

Set whether the aspect ratio of the displayed world area is maintained during resize operations of this panel, or when setDisplayedWorldArea(Rectangle2D) is called.

Note that this should usually be set to false when setResizingContents(boolean) is set to true.

Parameters:

maintainAspectRatio - Whether the aspect ratio is maintained

isMaintainAspectRatio

public final boolean isMaintainAspectRatio()

Returns whether the aspect ratio is maintained during resize operations or when setDisplayedWorldArea(Rectangle2D) is called

Returns:

Whether the aspect ratio is maintained during resize operations

setAntialiasing

public final void setAntialiasing(boolean antialiasing)

Set whether the antialiasing rendering hint should be enabled by default

Parameters:

antialiasing - Whether antialiasing should be enabled

isAntialiasing

public final boolean isAntialiasing()

Return whether the antialiasing rendering hint is enabled by default

Returns:

Whether antialiasing is enabled

addPainter

public final boolean addPainter(Painter painter)

Add the given Painter, which will perform painting operations in the paintComponent(Graphics) method. The painter will be added at the default layer (0). If the given painter is null, then this call will have no effect and false will be returned.

Parameters:

painter - The Painter to add

Returns:

Whether the painter was not yet contained in this viewer

addPainter

public final boolean addPainter(Painter painter,
                                int layer)

Add the given Painter, which will perform painting operations in the paintComponent(Graphics) method, on the specified layer. If the given painter is null, then this call will have no effect and false will be returned.

Parameters:

painter - The Painter to add

layer - The layer for the Painter

Returns:

Whether the painter was not yet contained in this viewer

removePainter

public final boolean removePainter(Painter painter)

Remove the given Painter from all layers that it is contained in

Parameters:

painter - The Painter to remove

Returns:

Whether the painter was contained in this viewer

removePainter

public final boolean removePainter(Painter painter,
                                   int layer)

Remove the given Painter from the specified layer

Parameters:

painter - The Painter to remove

layer - The layer from which the painter should be removed

Returns:

Whether the painter was contained in this layer

paintComponent

protected void paintComponent(java.awt.Graphics gr)

Overrides:

paintComponent in class javax.swing.JComponent

getWorldToScreen

public final java.awt.geom.AffineTransform getWorldToScreen()

Returns a copy of the current world-to-screen transform

Returns:

The world-to-screen transform

getScreenToWorld

public final java.awt.geom.AffineTransform getScreenToWorld()

Returns a copy of the screen-to-world transform

Returns:

The screen-to-world transform

transform

public final void transform(java.awt.geom.AffineTransform t)

Transform the contents of this viewer with the given transform

Parameters:

t - The transform

Throws:

java.lang.NullPointerException - if the given transform is null

java.lang.IllegalArgumentException - if the determinant of the given transform is 0.0, or NaN, or infinite

resetTransform

public final void resetTransform()

Reset this viewer to the identity transform

setTransform

public final void setTransform(java.awt.geom.AffineTransform t)

Set the world-to-screen transform of this viewer to the given transform.

Parameters:

t - The transform to set

Throws:

java.lang.NullPointerException - if the given transform is null

java.lang.IllegalArgumentException - if the determinant of the given transform is 0.0, or NaN, or infinite

zoom

public final void zoom(double screenCenterX,
                       double screenCenterY,
                       double factorX,
                       double factorY)

Zoom about the specified point (in screen coordinates) by the given factor.

This method will try to limit the zooming factor of this viewer in order to prevent rendering errors: When the zooming factor already is very large, then this method may not allow zooming in any further (and similarly, for zooming out when the zooming factor already is very small). But due to the limited precision of double computations, this limitation of the zoom may not always be effective - for example, when the translation is very large.

Parameters:

screenCenterX - The x-coordinate of the zooming center, in screen coordinates

screenCenterY - The y-coordinate of the zooming center, in screen coordinates

factorX - The zooming factor for the x-axis

factorY - The zooming factor for the y-axis

translate

public final void translate(double screenDx,
                            double screenDy)

Translate this viewer by the given delta, in screen coordinates

Parameters:

screenDx - The movement delta in x-direction, in screen coordinates

screenDy - The movement delta in y-direction, in screen coordinates

rotate

public final void rotate(double screenCenterX,
                         double screenCenterY,
                         double angleRad)

Rotate about the specified point (in screen coordinates) by the given angle (in radians)

Parameters:

screenCenterX - The x-coordinate of the zooming center, in screen coordinates

screenCenterY - The y-coordinate of the zooming center, in screen coordinates

angleRad - The angle, in radians

setDisplayedWorldArea

public final void setDisplayedWorldArea(double x,
                                        double y,
                                        double w,
                                        double h)

Set the area (in world coordinates) that should be shown.

This will adjust the scaling and translation so that at least the specified rectangle is visible (even when the view is rotated).

If this viewer is maintaining the aspect ratio, then the smallest area with the current aspect ratio will be visible that entirely contains the specified rectangle.

Parameters:

x - The x-coordinate

y - The y-coordinate

w - The width

h - The height

setDisplayedWorldArea

public final void setDisplayedWorldArea(java.awt.geom.Rectangle2D newWorldArea)

Set the area (in world coordinates) that should be shown.

This will adjust the scaling and translation so that at least the given rectangle is visible (even when the view is rotated).

If this viewer is maintaining the aspect ratio, then the smallest area with the current aspect ratio will be visible that entirely contains the given rectangle.

Parameters:

newWorldArea - The world area