- java.lang.Object
-
- java.awt.Graphics
-
- java.awt.Graphics2D
-
public abstract class Graphics2D extends Graphics
ThisGraphics2D
class extends theGraphics
class to provide more sophisticated control over geometry, coordinate transformations, color management, and text layout. This is the fundamental class for rendering 2-dimensional shapes, text and images on the Java(tm) platform.Coordinate Spaces
All coordinates passed to aGraphics2D
object are specified in a device-independent coordinate system called User Space, which is used by applications. TheGraphics2D
object contains anAffineTransform
object as part of its rendering state that defines how to convert coordinates from user space to device-dependent coordinates in Device Space.Coordinates in device space usually refer to individual device pixels and are aligned on the infinitely thin gaps between these pixels. Some
Graphics2D
objects can be used to capture rendering operations for storage into a graphics metafile for playback on a concrete device of unknown physical resolution at a later time. Since the resolution might not be known when the rendering operations are captured, theGraphics2D
Transform
is set up to transform user coordinates to a virtual device space that approximates the expected resolution of the target device. Further transformations might need to be applied at playback time if the estimate is incorrect.Some of the operations performed by the rendering attribute objects occur in the device space, but all
Graphics2D
methods take user space coordinates.Every
Graphics2D
object is associated with a target that defines where rendering takes place. AGraphicsConfiguration
object defines the characteristics of the rendering target, such as pixel format and resolution. The same rendering target is used throughout the life of aGraphics2D
object.When creating a
Graphics2D
object, theGraphicsConfiguration
specifies the default transform for the target of theGraphics2D
(aComponent
orImage
). This default transform maps the user space coordinate system to screen and printer device coordinates such that the origin maps to the upper left hand corner of the target region of the device with increasing X coordinates extending to the right and increasing Y coordinates extending downward. The scaling of the default transform is set to identity for those devices that are close to 72 dpi, such as screen devices. The scaling of the default transform is set to approximately 72 user space coordinates per square inch for high resolution devices, such as printers. For image buffers, the default transform is theIdentity
transform.Rendering Process
The Rendering Process can be broken down into four phases that are controlled by theGraphics2D
rendering attributes. The renderer can optimize many of these steps, either by caching the results for future calls, by collapsing multiple virtual steps into a single operation, or by recognizing various attributes as common simple cases that can be eliminated by modifying other parts of the operation.The steps in the rendering process are:
- Determine what to render.
-
Constrain the rendering operation to the current
Clip
. TheClip
is specified by aShape
in user space and is controlled by the program using the various clip manipulation methods ofGraphics
andGraphics2D
. This user clip is transformed into device space by the currentTransform
and combined with the device clip, which is defined by the visibility of windows and device extents. The combination of the user clip and device clip defines the composite clip, which determines the final clipping region. The user clip is not modified by the rendering system to reflect the resulting composite clip. - Determine what colors to render.
-
Apply the colors to the destination drawing surface using the current
Composite
attribute in theGraphics2D
context.
The three types of rendering operations, along with details of each of their particular rendering processes are:-
Shape
operations-
If the operation is a
draw(Shape)
operation, then thecreateStrokedShape
method on the currentStroke
attribute in theGraphics2D
context is used to construct a newShape
object that contains the outline of the specifiedShape
. -
The
Shape
is transformed from user space to device space using the currentTransform
in theGraphics2D
context. -
The outline of the
Shape
is extracted using thegetPathIterator
method ofShape
, which returns aPathIterator
object that iterates along the boundary of theShape
. -
If the
Graphics2D
object cannot handle the curved segments that thePathIterator
object returns then it can call the alternategetPathIterator
method ofShape
, which flattens theShape
. -
The current
Paint
in theGraphics2D
context is queried for aPaintContext
, which specifies the colors to render in device space.
-
If the operation is a
-
Text operations
-
The following steps are used to determine the set of glyphs required
to render the indicated
String
:-
If the argument is a
String
, then the currentFont
in theGraphics2D
context is asked to convert the Unicode characters in theString
into a set of glyphs for presentation with whatever basic layout and shaping algorithms the font implements. -
If the argument is an
AttributedCharacterIterator
, the iterator is asked to convert itself to aTextLayout
using its embedded font attributes. TheTextLayout
implements more sophisticated glyph layout algorithms that perform Unicode bi-directional layout adjustments automatically for multiple fonts of differing writing directions. -
If the argument is a
GlyphVector
, then theGlyphVector
object already contains the appropriate font-specific glyph codes with explicit coordinates for the position of each glyph.
-
If the argument is a
-
The current
Font
is queried to obtain outlines for the indicated glyphs. These outlines are treated as shapes in user space relative to the position of each glyph that was determined in step 1. -
The character outlines are filled as indicated above
under
Shape
operations. -
The current
Paint
is queried for aPaintContext
, which specifies the colors to render in device space.
-
The following steps are used to determine the set of glyphs required
to render the indicated
-
Image
Operations-
The region of interest is defined by the bounding box of the source
Image
. This bounding box is specified in Image Space, which is theImage
object's local coordinate system. -
If an
AffineTransform
is passed todrawImage(Image, AffineTransform, ImageObserver)
, theAffineTransform
is used to transform the bounding box from image space to user space. If noAffineTransform
is supplied, the bounding box is treated as if it is already in user space. -
The bounding box of the source
Image
is transformed from user space into device space using the currentTransform
. Note that the result of transforming the bounding box does not necessarily result in a rectangular region in device space. -
The
Image
object determines what colors to render, sampled according to the source to destination coordinate mapping specified by the currentTransform
and the optional image transform.
-
The region of interest is defined by the bounding box of the source
Default Rendering Attributes
The default values for theGraphics2D
rendering attributes are:Paint
- The color of the
Component
. Font
- The
Font
of theComponent
. Stroke
- A square pen with a linewidth of 1, no dashing, miter segment joins and square end caps.
Transform
- The
getDefaultTransform
for theGraphicsConfiguration
of theComponent
. Composite
- The
AlphaComposite.SRC_OVER
rule. Clip
- No rendering
Clip
, the output is clipped to theComponent
.
Rendering Compatibility Issues
The JDK(tm) 1.1 rendering model is based on a pixelization model that specifies that coordinates are infinitely thin, lying between the pixels. Drawing operations are performed using a one-pixel wide pen that fills the pixel below and to the right of the anchor point on the path. The JDK 1.1 rendering model is consistent with the capabilities of most of the existing class of platform renderers that need to resolve integer coordinates to a discrete pen that must fall completely on a specified number of pixels.The Java 2D(tm) (Java(tm) 2 platform) API supports antialiasing renderers. A pen with a width of one pixel does not need to fall completely on pixel N as opposed to pixel N+1. The pen can fall partially on both pixels. It is not necessary to choose a bias direction for a wide pen since the blending that occurs along the pen traversal edges makes the sub-pixel position of the pen visible to the user. On the other hand, when antialiasing is turned off by setting the
KEY_ANTIALIASING
hint key to theVALUE_ANTIALIAS_OFF
hint value, the renderer might need to apply a bias to determine which pixel to modify when the pen is straddling a pixel boundary, such as when it is drawn along an integer coordinate in device space. While the capabilities of an antialiasing renderer make it no longer necessary for the rendering model to specify a bias for the pen, it is desirable for the antialiasing and non-antialiasing renderers to perform similarly for the common cases of drawing one-pixel wide horizontal and vertical lines on the screen. To ensure that turning on antialiasing by setting theKEY_ANTIALIASING
hint key toVALUE_ANTIALIAS_ON
does not cause such lines to suddenly become twice as wide and half as opaque, it is desirable to have the model specify a path for such lines so that they completely cover a particular set of pixels to help increase their crispness.Java 2D API maintains compatibility with JDK 1.1 rendering behavior, such that legacy operations and existing renderer behavior is unchanged under Java 2D API. Legacy methods that map onto general
draw
andfill
methods are defined, which clearly indicates howGraphics2D
extendsGraphics
based on settings ofStroke
andTransform
attributes and rendering hints. The definition performs identically under default attribute settings. For example, the defaultStroke
is aBasicStroke
with a width of 1 and no dashing and the default Transform for screen drawing is an Identity transform.The following two rules provide predictable rendering behavior whether aliasing or antialiasing is being used.
- Device coordinates are defined to be between device pixels which avoids any inconsistent results between aliased and antaliased rendering. If coordinates were defined to be at a pixel's center, some of the pixels covered by a shape, such as a rectangle, would only be half covered. With aliased rendering, the half covered pixels would either be rendered inside the shape or outside the shape. With anti-aliased rendering, the pixels on the entire edge of the shape would be half covered. On the other hand, since coordinates are defined to be between pixels, a shape like a rectangle would have no half covered pixels, whether or not it is rendered using antialiasing.
- Lines and paths stroked using the
BasicStroke
object may be "normalized" to provide consistent rendering of the outlines when positioned at various points on the drawable and whether drawn with aliased or antialiased rendering. This normalization process is controlled by theKEY_STROKE_CONTROL
hint. The exact normalization algorithm is not specified, but the goals of this normalization are to ensure that lines are rendered with consistent visual appearance regardless of how they fall on the pixel grid and to promote more solid horizontal and vertical lines in antialiased mode so that they resemble their non-antialiased counterparts more closely. A typical normalization step might promote antialiased line endpoints to pixel centers to reduce the amount of blending or adjust the subpixel positioning of non-antialiased lines so that the floating point line widths round to even or odd pixel counts with equal likelihood. This process can move endpoints by up to half a pixel (usually towards positive infinity along both axes) to promote these consistent results.
The following definitions of general legacy methods perform identically to previously specified behavior under default attribute settings:
-
For
fill
operations, includingfillRect
,fillRoundRect
,fillOval
,fillArc
,fillPolygon
, andclearRect
,fill
can now be called with the desiredShape
. For example, when filling a rectangle:fill(new Rectangle(x, y, w, h));
is called. -
Similarly, for draw operations, including
drawLine
,drawRect
,drawRoundRect
,drawOval
,drawArc
,drawPolyline
, anddrawPolygon
,draw
can now be called with the desiredShape
. For example, when drawing a rectangle:draw(new Rectangle(x, y, w, h));
is called. -
The
draw3DRect
andfill3DRect
methods were implemented in terms of thedrawLine
andfillRect
methods in theGraphics
class which would predicate their behavior upon the currentStroke
andPaint
objects in aGraphics2D
context. This class overrides those implementations with versions that use the currentColor
exclusively, overriding the currentPaint
and which usesfillRect
to describe the exact same behavior as the preexisting methods regardless of the setting of the currentStroke
.
Graphics
class defines only thesetColor
method to control the color to be painted. Since the Java 2D API extends theColor
object to implement the newPaint
interface, the existingsetColor
method is now a convenience method for setting the currentPaint
attribute to aColor
object.setColor(c)
is equivalent tosetPaint(c)
.The
Graphics
class defines two methods for controlling how colors are applied to the destination.-
The
setPaintMode
method is implemented as a convenience method to set the defaultComposite
, equivalent tosetComposite(new AlphaComposite.SrcOver)
. -
The
setXORMode(Color xorcolor)
method is implemented as a convenience method to set a specialComposite
object that ignores theAlpha
components of source colors and sets the destination color to the value:dstpixel = (PixelOf(srccolor) ^ PixelOf(xorcolor) ^ dstpixel);
- See Also:
RenderingHints
-
-
Constructor Summary
Constructors Modifier Constructor and Description protected
Graphics2D()
Constructs a newGraphics2D
object.
-
Method Summary
Methods Modifier and Type Method and Description abstract void
addRenderingHints(Map<?,?> hints)
Sets the values of an arbitrary number of preferences for the rendering algorithms.abstract void
clip(Shape s)
Intersects the currentClip
with the interior of the specifiedShape
and sets theClip
to the resulting intersection.abstract void
draw(Shape s)
Strokes the outline of aShape
using the settings of the currentGraphics2D
context.void
draw3DRect(int x, int y, int width, int height, boolean raised)
Draws a 3-D highlighted outline of the specified rectangle.abstract void
drawGlyphVector(GlyphVector g, float x, float y)
Renders the text of the specifiedGlyphVector
using theGraphics2D
context's rendering attributes.abstract void
drawImage(BufferedImage img, BufferedImageOp op, int x, int y)
Renders aBufferedImage
that is filtered with aBufferedImageOp
.abstract boolean
drawImage(Image img, AffineTransform xform, ImageObserver obs)
Renders an image, applying a transform from image space into user space before drawing.abstract void
drawRenderableImage(RenderableImage img, AffineTransform xform)
Renders aRenderableImage
, applying a transform from image space into user space before drawing.abstract void
drawRenderedImage(RenderedImage img, AffineTransform xform)
Renders aRenderedImage
, applying a transform from image space into user space before drawing.abstract void
drawString(AttributedCharacterIterator iterator, float x, float y)
Renders the text of the specified iterator applying its attributes in accordance with the specification of theTextAttribute
class.abstract void
drawString(AttributedCharacterIterator iterator, int x, int y)
Renders the text of the specified iterator applying its attributes in accordance with the specification of theTextAttribute
class.abstract void
drawString(String str, float x, float y)
Renders the text specified by the specifiedString
, using the current text attribute state in theGraphics2D
context.abstract void
drawString(String str, int x, int y)
Renders the text of the specifiedString
, using the current text attribute state in theGraphics2D
context.abstract void
fill(Shape s)
Fills the interior of aShape
using the settings of theGraphics2D
context.void
fill3DRect(int x, int y, int width, int height, boolean raised)
Paints a 3-D highlighted rectangle filled with the current color.abstract Color
getBackground()
Returns the background color used for clearing a region.abstract Composite
getComposite()
Returns the currentComposite
in theGraphics2D
context.abstract GraphicsConfiguration
getDeviceConfiguration()
Returns the device configuration associated with thisGraphics2D
.abstract FontRenderContext
getFontRenderContext()
Get the rendering context of theFont
within thisGraphics2D
context.abstract Paint
getPaint()
Returns the currentPaint
of theGraphics2D
context.abstract Object
getRenderingHint(RenderingHints.Key hintKey)
Returns the value of a single preference for the rendering algorithms.abstract RenderingHints
getRenderingHints()
Gets the preferences for the rendering algorithms.abstract Stroke
getStroke()
Returns the currentStroke
in theGraphics2D
context.abstract AffineTransform
getTransform()
Returns a copy of the currentTransform
in theGraphics2D
context.abstract boolean
hit(Rectangle rect, Shape s, boolean onStroke)
Checks whether or not the specifiedShape
intersects the specifiedRectangle
, which is in device space.abstract void
rotate(double theta)
Concatenates the currentGraphics2D
Transform
with a rotation transform.abstract void
rotate(double theta, double x, double y)
Concatenates the currentGraphics2D
Transform
with a translated rotation transform.abstract void
scale(double sx, double sy)
Concatenates the currentGraphics2D
Transform
with a scaling transformation Subsequent rendering is resized according to the specified scaling factors relative to the previous scaling.abstract void
setBackground(Color color)
Sets the background color for theGraphics2D
context.abstract void
setComposite(Composite comp)
Sets theComposite
for theGraphics2D
context.abstract void
setPaint(Paint paint)
Sets thePaint
attribute for theGraphics2D
context.abstract void
setRenderingHint(RenderingHints.Key hintKey, Object hintValue)
Sets the value of a single preference for the rendering algorithms.abstract void
setRenderingHints(Map<?,?> hints)
Replaces the values of all preferences for the rendering algorithms with the specifiedhints
.abstract void
setStroke(Stroke s)
Sets theStroke
for theGraphics2D
context.abstract void
setTransform(AffineTransform Tx)
Overwrites the Transform in theGraphics2D
context.abstract void
shear(double shx, double shy)
Concatenates the currentGraphics2D
Transform
with a shearing transform.abstract void
transform(AffineTransform Tx)
Composes anAffineTransform
object with theTransform
in thisGraphics2D
according to the rule last-specified-first-applied.abstract void
translate(double tx, double ty)
Concatenates the currentGraphics2D
Transform
with a translation transform.abstract void
translate(int x, int y)
Translates the origin of theGraphics2D
context to the point (x, y) in the current coordinate system.-
Methods inherited from class java.awt.Graphics
clearRect, clipRect, copyArea, create, create, dispose, drawArc, drawBytes, drawChars, drawImage, drawImage, drawImage, drawImage, drawImage, drawImage, drawLine, drawOval, drawPolygon, drawPolygon, drawPolyline, drawRect, drawRoundRect, fillArc, fillOval, fillPolygon, fillPolygon, fillRect, fillRoundRect, finalize, getClip, getClipBounds, getClipBounds, getClipRect, getColor, getFont, getFontMetrics, getFontMetrics, hitClip, setClip, setClip, setColor, setFont, setPaintMode, setXORMode, toString
-
-
-
-
Constructor Detail
-
Graphics2D
protected Graphics2D()
Constructs a newGraphics2D
object. SinceGraphics2D
is an abstract class, and since it must be customized by subclasses for different output devices,Graphics2D
objects cannot be created directly. Instead,Graphics2D
objects must be obtained from anotherGraphics2D
object, created by aComponent
, or obtained from images such asBufferedImage
objects.- See Also:
Component.getGraphics()
,Graphics.create()
-
-
Method Detail
-
draw3DRect
public void draw3DRect(int x, int y, int width, int height, boolean raised)
Draws a 3-D highlighted outline of the specified rectangle. The edges of the rectangle are highlighted so that they appear to be beveled and lit from the upper left corner.The colors used for the highlighting effect are determined based on the current color. The resulting rectangle covers an area that is
width + 1
pixels wide byheight + 1
pixels tall. This method uses the currentColor
exclusively and ignores the currentPaint
.- Overrides:
draw3DRect
in classGraphics
- Parameters:
x
- the x coordinate of the rectangle to be drawn.y
- the y coordinate of the rectangle to be drawn.width
- the width of the rectangle to be drawn.height
- the height of the rectangle to be drawn.raised
- a boolean that determines whether the rectangle appears to be raised above the surface or sunk into the surface.- See Also:
Graphics.fill3DRect(int, int, int, int, boolean)
-
fill3DRect
public void fill3DRect(int x, int y, int width, int height, boolean raised)
Paints a 3-D highlighted rectangle filled with the current color. The edges of the rectangle are highlighted so that it appears as if the edges were beveled and lit from the upper left corner. The colors used for the highlighting effect and for filling are determined from the currentColor
. This method uses the currentColor
exclusively and ignores the currentPaint
.- Overrides:
fill3DRect
in classGraphics
- Parameters:
x
- the x coordinate of the rectangle to be filled.y
- the y coordinate of the rectangle to be filled.width
- the width of the rectangle to be filled.height
- the height of the rectangle to be filled.raised
- a boolean value that determines whether the rectangle appears to be raised above the surface or etched into the surface.- See Also:
Graphics.draw3DRect(int, int, int, int, boolean)
-
draw
public abstract void draw(Shape s)
Strokes the outline of aShape
using the settings of the currentGraphics2D
context. The rendering attributes applied include theClip
,Transform
,Paint
,Composite
andStroke
attributes.- Parameters:
s
- theShape
to be rendered- See Also:
setStroke(java.awt.Stroke)
,setPaint(java.awt.Paint)
,Graphics.setColor(java.awt.Color)
,transform(java.awt.geom.AffineTransform)
,setTransform(java.awt.geom.AffineTransform)
,clip(java.awt.Shape)
,Graphics.setClip(int, int, int, int)
,setComposite(java.awt.Composite)
-
drawImage
public abstract boolean drawImage(Image img, AffineTransform xform, ImageObserver obs)
Renders an image, applying a transform from image space into user space before drawing. The transformation from user space into device space is done with the currentTransform
in theGraphics2D
. The specified transformation is applied to the image before the transform attribute in theGraphics2D
context is applied. The rendering attributes applied include theClip
,Transform
, andComposite
attributes. Note that no rendering is done if the specified transform is noninvertible.- Parameters:
img
- the specified image to be rendered. This method does nothing ifimg
is null.xform
- the transformation from image space into user spaceobs
- theImageObserver
to be notified as more of theImage
is converted- Returns:
true
if theImage
is fully loaded and completely rendered, or if it's null;false
if theImage
is still being loaded.- See Also:
transform(java.awt.geom.AffineTransform)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,clip(java.awt.Shape)
,Graphics.setClip(int, int, int, int)
-
drawImage
public abstract void drawImage(BufferedImage img, BufferedImageOp op, int x, int y)
Renders aBufferedImage
that is filtered with aBufferedImageOp
. The rendering attributes applied include theClip
,Transform
andComposite
attributes. This is equivalent to:img1 = op.filter(img, null); drawImage(img1, new AffineTransform(1f,0f,0f,1f,x,y), null);
- Parameters:
op
- the filter to be applied to the image before renderingimg
- the specifiedBufferedImage
to be rendered. This method does nothing ifimg
is null.x
- the x coordinate of the location in user space where the upper left corner of the image is renderedy
- the y coordinate of the location in user space where the upper left corner of the image is rendered- See Also:
transform(java.awt.geom.AffineTransform)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,clip(java.awt.Shape)
,Graphics.setClip(int, int, int, int)
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drawRenderedImage
public abstract void drawRenderedImage(RenderedImage img, AffineTransform xform)
Renders aRenderedImage
, applying a transform from image space into user space before drawing. The transformation from user space into device space is done with the currentTransform
in theGraphics2D
. The specified transformation is applied to the image before the transform attribute in theGraphics2D
context is applied. The rendering attributes applied include theClip
,Transform
, andComposite
attributes. Note that no rendering is done if the specified transform is noninvertible.- Parameters:
img
- the image to be rendered. This method does nothing ifimg
is null.xform
- the transformation from image space into user space- See Also:
transform(java.awt.geom.AffineTransform)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,clip(java.awt.Shape)
,Graphics.setClip(int, int, int, int)
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drawRenderableImage
public abstract void drawRenderableImage(RenderableImage img, AffineTransform xform)
Renders aRenderableImage
, applying a transform from image space into user space before drawing. The transformation from user space into device space is done with the currentTransform
in theGraphics2D
. The specified transformation is applied to the image before the transform attribute in theGraphics2D
context is applied. The rendering attributes applied include theClip
,Transform
, andComposite
attributes. Note that no rendering is done if the specified transform is noninvertible.Rendering hints set on the
Graphics2D
object might be used in rendering theRenderableImage
. If explicit control is required over specific hints recognized by a specificRenderableImage
, or if knowledge of which hints are used is required, then aRenderedImage
should be obtained directly from theRenderableImage
and rendered usingdrawRenderedImage
.- Parameters:
img
- the image to be rendered. This method does nothing ifimg
is null.xform
- the transformation from image space into user space- See Also:
transform(java.awt.geom.AffineTransform)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,clip(java.awt.Shape)
,Graphics.setClip(int, int, int, int)
,drawRenderedImage(java.awt.image.RenderedImage, java.awt.geom.AffineTransform)
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drawString
public abstract void drawString(String str, int x, int y)
Renders the text of the specifiedString
, using the current text attribute state in theGraphics2D
context. The baseline of the first character is at position (x, y) in the User Space. The rendering attributes applied include theClip
,Transform
,Paint
,Font
andComposite
attributes. For characters in script systems such as Hebrew and Arabic, the glyphs can be rendered from right to left, in which case the coordinate supplied is the location of the leftmost character on the baseline.- Specified by:
drawString
in classGraphics
- Parameters:
str
- the string to be renderedx
- the x coordinate of the location where theString
should be renderedy
- the y coordinate of the location where theString
should be rendered- Throws:
NullPointerException
- ifstr
isnull
- Since:
- JDK1.0
- See Also:
Graphics.drawBytes(byte[], int, int, int, int)
,Graphics.drawChars(char[], int, int, int, int)
-
drawString
public abstract void drawString(String str, float x, float y)
Renders the text specified by the specifiedString
, using the current text attribute state in theGraphics2D
context. The baseline of the first character is at position (x, y) in the User Space. The rendering attributes applied include theClip
,Transform
,Paint
,Font
andComposite
attributes. For characters in script systems such as Hebrew and Arabic, the glyphs can be rendered from right to left, in which case the coordinate supplied is the location of the leftmost character on the baseline.- Parameters:
str
- theString
to be renderedx
- the x coordinate of the location where theString
should be renderedy
- the y coordinate of the location where theString
should be rendered- Throws:
NullPointerException
- ifstr
isnull
- See Also:
setPaint(java.awt.Paint)
,Graphics.setColor(java.awt.Color)
,Graphics.setFont(java.awt.Font)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,Graphics.setClip(int, int, int, int)
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drawString
public abstract void drawString(AttributedCharacterIterator iterator, int x, int y)
Renders the text of the specified iterator applying its attributes in accordance with the specification of theTextAttribute
class.The baseline of the first character is at position (x, y) in User Space. For characters in script systems such as Hebrew and Arabic, the glyphs can be rendered from right to left, in which case the coordinate supplied is the location of the leftmost character on the baseline.
- Specified by:
drawString
in classGraphics
- Parameters:
iterator
- the iterator whose text is to be renderedx
- the x coordinate where the iterator's text is to be renderedy
- the y coordinate where the iterator's text is to be rendered- Throws:
NullPointerException
- ifiterator
isnull
- See Also:
setPaint(java.awt.Paint)
,Graphics.setColor(java.awt.Color)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,Graphics.setClip(int, int, int, int)
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drawString
public abstract void drawString(AttributedCharacterIterator iterator, float x, float y)
Renders the text of the specified iterator applying its attributes in accordance with the specification of theTextAttribute
class.The baseline of the first character is at position (x, y) in User Space. For characters in script systems such as Hebrew and Arabic, the glyphs can be rendered from right to left, in which case the coordinate supplied is the location of the leftmost character on the baseline.
- Parameters:
iterator
- the iterator whose text is to be renderedx
- the x coordinate where the iterator's text is to be renderedy
- the y coordinate where the iterator's text is to be rendered- Throws:
NullPointerException
- ifiterator
isnull
- See Also:
setPaint(java.awt.Paint)
,Graphics.setColor(java.awt.Color)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,Graphics.setClip(int, int, int, int)
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drawGlyphVector
public abstract void drawGlyphVector(GlyphVector g, float x, float y)
Renders the text of the specifiedGlyphVector
using theGraphics2D
context's rendering attributes. The rendering attributes applied include theClip
,Transform
,Paint
, andComposite
attributes. TheGlyphVector
specifies individual glyphs from aFont
. TheGlyphVector
can also contain the glyph positions. This is the fastest way to render a set of characters to the screen.- Parameters:
g
- theGlyphVector
to be renderedx
- the x position in User Space where the glyphs should be renderedy
- the y position in User Space where the glyphs should be rendered- Throws:
NullPointerException
- ifg
isnull
.- See Also:
Font.createGlyphVector(java.awt.font.FontRenderContext, java.lang.String)
,GlyphVector
,setPaint(java.awt.Paint)
,Graphics.setColor(java.awt.Color)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,Graphics.setClip(int, int, int, int)
-
fill
public abstract void fill(Shape s)
Fills the interior of aShape
using the settings of theGraphics2D
context. The rendering attributes applied include theClip
,Transform
,Paint
, andComposite
.- Parameters:
s
- theShape
to be filled- See Also:
setPaint(java.awt.Paint)
,Graphics.setColor(java.awt.Color)
,transform(java.awt.geom.AffineTransform)
,setTransform(java.awt.geom.AffineTransform)
,setComposite(java.awt.Composite)
,clip(java.awt.Shape)
,Graphics.setClip(int, int, int, int)
-
hit
public abstract boolean hit(Rectangle rect, Shape s, boolean onStroke)
Checks whether or not the specifiedShape
intersects the specifiedRectangle
, which is in device space. IfonStroke
is false, this method checks whether or not the interior of the specifiedShape
intersects the specifiedRectangle
. IfonStroke
istrue
, this method checks whether or not theStroke
of the specifiedShape
outline intersects the specifiedRectangle
. The rendering attributes taken into account include theClip
,Transform
, andStroke
attributes.- Parameters:
rect
- the area in device space to check for a hits
- theShape
to check for a hitonStroke
- flag used to choose between testing the stroked or the filled shape. If the flag istrue
, theStroke
oultine is tested. If the flag isfalse
, the filledShape
is tested.- Returns:
true
if there is a hit;false
otherwise.- See Also:
setStroke(java.awt.Stroke)
,fill(java.awt.Shape)
,draw(java.awt.Shape)
,transform(java.awt.geom.AffineTransform)
,setTransform(java.awt.geom.AffineTransform)
,clip(java.awt.Shape)
,Graphics.setClip(int, int, int, int)
-
getDeviceConfiguration
public abstract GraphicsConfiguration getDeviceConfiguration()
Returns the device configuration associated with thisGraphics2D
.- Returns:
- the device configuration of this
Graphics2D
.
-
setComposite
public abstract void setComposite(Composite comp)
Sets theComposite
for theGraphics2D
context. TheComposite
is used in all drawing methods such asdrawImage
,drawString
,draw
, andfill
. It specifies how new pixels are to be combined with the existing pixels on the graphics device during the rendering process.If this
Graphics2D
context is drawing to aComponent
on the display screen and theComposite
is a custom object rather than an instance of theAlphaComposite
class, and if there is a security manager, itscheckPermission
method is called with anAWTPermission("readDisplayPixels")
permission.- Parameters:
comp
- theComposite
object to be used for rendering- Throws:
SecurityException
- if a customComposite
object is being used to render to the screen and a security manager is set and itscheckPermission
method does not allow the operation.- See Also:
Graphics.setXORMode(java.awt.Color)
,Graphics.setPaintMode()
,getComposite()
,AlphaComposite
,SecurityManager.checkPermission(java.security.Permission)
,AWTPermission
-
setPaint
public abstract void setPaint(Paint paint)
Sets thePaint
attribute for theGraphics2D
context. Calling this method with anull
Paint
object does not have any effect on the currentPaint
attribute of thisGraphics2D
.- Parameters:
paint
- thePaint
object to be used to generate color during the rendering process, ornull
- See Also:
Graphics.setColor(java.awt.Color)
,getPaint()
,GradientPaint
,TexturePaint
-
setStroke
public abstract void setStroke(Stroke s)
Sets theStroke
for theGraphics2D
context.- Parameters:
s
- theStroke
object to be used to stroke aShape
during the rendering process- See Also:
BasicStroke
,getStroke()
-
setRenderingHint
public abstract void setRenderingHint(RenderingHints.Key hintKey, Object hintValue)
Sets the value of a single preference for the rendering algorithms. Hint categories include controls for rendering quality and overall time/quality trade-off in the rendering process. Refer to theRenderingHints
class for definitions of some common keys and values.- Parameters:
hintKey
- the key of the hint to be set.hintValue
- the value indicating preferences for the specified hint category.- See Also:
getRenderingHint(RenderingHints.Key)
,RenderingHints
-
getRenderingHint
public abstract Object getRenderingHint(RenderingHints.Key hintKey)
Returns the value of a single preference for the rendering algorithms. Hint categories include controls for rendering quality and overall time/quality trade-off in the rendering process. Refer to theRenderingHints
class for definitions of some common keys and values.- Parameters:
hintKey
- the key corresponding to the hint to get.- Returns:
- an object representing the value for the specified hint key.
Some of the keys and their associated values are defined in the
RenderingHints
class. - See Also:
RenderingHints
,setRenderingHint(RenderingHints.Key, Object)
-
setRenderingHints
public abstract void setRenderingHints(Map<?,?> hints)
Replaces the values of all preferences for the rendering algorithms with the specifiedhints
. The existing values for all rendering hints are discarded and the new set of known hints and values are initialized from the specifiedMap
object. Hint categories include controls for rendering quality and overall time/quality trade-off in the rendering process. Refer to theRenderingHints
class for definitions of some common keys and values.- Parameters:
hints
- the rendering hints to be set- See Also:
getRenderingHints()
,RenderingHints
-
addRenderingHints
public abstract void addRenderingHints(Map<?,?> hints)
Sets the values of an arbitrary number of preferences for the rendering algorithms. Only values for the rendering hints that are present in the specifiedMap
object are modified. All other preferences not present in the specified object are left unmodified. Hint categories include controls for rendering quality and overall time/quality trade-off in the rendering process. Refer to theRenderingHints
class for definitions of some common keys and values.- Parameters:
hints
- the rendering hints to be set- See Also:
RenderingHints
-
getRenderingHints
public abstract RenderingHints getRenderingHints()
Gets the preferences for the rendering algorithms. Hint categories include controls for rendering quality and overall time/quality trade-off in the rendering process. Returns all of the hint key/value pairs that were ever specified in one operation. Refer to theRenderingHints
class for definitions of some common keys and values.- Returns:
- a reference to an instance of
RenderingHints
that contains the current preferences. - See Also:
RenderingHints
,setRenderingHints(Map)
-
translate
public abstract void translate(int x, int y)
Translates the origin of theGraphics2D
context to the point (x, y) in the current coordinate system. Modifies theGraphics2D
context so that its new origin corresponds to the point (x, y) in theGraphics2D
context's former coordinate system. All coordinates used in subsequent rendering operations on this graphics context are relative to this new origin.
-
translate
public abstract void translate(double tx, double ty)
Concatenates the currentGraphics2D
Transform
with a translation transform. Subsequent rendering is translated by the specified distance relative to the previous position. This is equivalent to calling transform(T), where T is anAffineTransform
represented by the following matrix:[ 1 0 tx ] [ 0 1 ty ] [ 0 0 1 ]
- Parameters:
tx
- the distance to translate along the x-axisty
- the distance to translate along the y-axis
-
rotate
public abstract void rotate(double theta)
Concatenates the currentGraphics2D
Transform
with a rotation transform. Subsequent rendering is rotated by the specified radians relative to the previous origin. This is equivalent to callingtransform(R)
, where R is anAffineTransform
represented by the following matrix:[ cos(theta) -sin(theta) 0 ] [ sin(theta) cos(theta) 0 ] [ 0 0 1 ]
Rotating with a positive angle theta rotates points on the positive x axis toward the positive y axis.- Parameters:
theta
- the angle of rotation in radians
-
rotate
public abstract void rotate(double theta, double x, double y)
Concatenates the currentGraphics2D
Transform
with a translated rotation transform. Subsequent rendering is transformed by a transform which is constructed by translating to the specified location, rotating by the specified radians, and translating back by the same amount as the original translation. This is equivalent to the following sequence of calls:translate(x, y); rotate(theta); translate(-x, -y);
Rotating with a positive angle theta rotates points on the positive x axis toward the positive y axis.- Parameters:
theta
- the angle of rotation in radiansx
- the x coordinate of the origin of the rotationy
- the y coordinate of the origin of the rotation
-
scale
public abstract void scale(double sx, double sy)
Concatenates the currentGraphics2D
Transform
with a scaling transformation Subsequent rendering is resized according to the specified scaling factors relative to the previous scaling. This is equivalent to callingtransform(S)
, where S is anAffineTransform
represented by the following matrix:[ sx 0 0 ] [ 0 sy 0 ] [ 0 0 1 ]
- Parameters:
sx
- the amount by which X coordinates in subsequent rendering operations are multiplied relative to previous rendering operations.sy
- the amount by which Y coordinates in subsequent rendering operations are multiplied relative to previous rendering operations.
-
shear
public abstract void shear(double shx, double shy)
Concatenates the currentGraphics2D
Transform
with a shearing transform. Subsequent renderings are sheared by the specified multiplier relative to the previous position. This is equivalent to callingtransform(SH)
, where SH is anAffineTransform
represented by the following matrix:[ 1 shx 0 ] [ shy 1 0 ] [ 0 0 1 ]
- Parameters:
shx
- the multiplier by which coordinates are shifted in the positive X axis direction as a function of their Y coordinateshy
- the multiplier by which coordinates are shifted in the positive Y axis direction as a function of their X coordinate
-
transform
public abstract void transform(AffineTransform Tx)
Composes anAffineTransform
object with theTransform
in thisGraphics2D
according to the rule last-specified-first-applied. If the currentTransform
is Cx, the result of composition with Tx is a newTransform
Cx'. Cx' becomes the currentTransform
for thisGraphics2D
. Transforming a point p by the updatedTransform
Cx' is equivalent to first transforming p by Tx and then transforming the result by the originalTransform
Cx. In other words, Cx'(p) = Cx(Tx(p)). A copy of the Tx is made, if necessary, so further modifications to Tx do not affect rendering.- Parameters:
Tx
- theAffineTransform
object to be composed with the currentTransform
- See Also:
setTransform(java.awt.geom.AffineTransform)
,AffineTransform
-
setTransform
public abstract void setTransform(AffineTransform Tx)
Overwrites the Transform in theGraphics2D
context. WARNING: This method should never be used to apply a new coordinate transform on top of an existing transform because theGraphics2D
might already have a transform that is needed for other purposes, such as rendering Swing components or applying a scaling transformation to adjust for the resolution of a printer.To add a coordinate transform, use the
transform
,rotate
,scale
, orshear
methods. ThesetTransform
method is intended only for restoring the originalGraphics2D
transform after rendering, as shown in this example:// Get the current transform AffineTransform saveAT = g2.getTransform(); // Perform transformation g2d.transform(...); // Render g2d.draw(...); // Restore original transform g2d.setTransform(saveAT);
- Parameters:
Tx
- theAffineTransform
that was retrieved from thegetTransform
method- See Also:
transform(java.awt.geom.AffineTransform)
,getTransform()
,AffineTransform
-
getTransform
public abstract AffineTransform getTransform()
Returns a copy of the currentTransform
in theGraphics2D
context.- Returns:
- the current
AffineTransform
in theGraphics2D
context. - See Also:
transform(java.awt.geom.AffineTransform)
,setTransform(java.awt.geom.AffineTransform)
-
getPaint
public abstract Paint getPaint()
Returns the currentPaint
of theGraphics2D
context.- Returns:
- the current
Graphics2D
Paint
, which defines a color or pattern. - See Also:
setPaint(java.awt.Paint)
,Graphics.setColor(java.awt.Color)
-
getComposite
public abstract Composite getComposite()
Returns the currentComposite
in theGraphics2D
context.- Returns:
- the current
Graphics2D
Composite
, which defines a compositing style. - See Also:
setComposite(java.awt.Composite)
-
setBackground
public abstract void setBackground(Color color)
Sets the background color for theGraphics2D
context. The background color is used for clearing a region. When aGraphics2D
is constructed for aComponent
, the background color is inherited from theComponent
. Setting the background color in theGraphics2D
context only affects the subsequentclearRect
calls and not the background color of theComponent
. To change the background of theComponent
, use appropriate methods of theComponent
.- Parameters:
color
- the background color that isused in subsequent calls toclearRect
- See Also:
getBackground()
,Graphics.clearRect(int, int, int, int)
-
getBackground
public abstract Color getBackground()
Returns the background color used for clearing a region.- Returns:
- the current
Graphics2D
Color
, which defines the background color. - See Also:
setBackground(java.awt.Color)
-
getStroke
public abstract Stroke getStroke()
Returns the currentStroke
in theGraphics2D
context.- Returns:
- the current
Graphics2D
Stroke
, which defines the line style. - See Also:
setStroke(java.awt.Stroke)
-
clip
public abstract void clip(Shape s)
Intersects the currentClip
with the interior of the specifiedShape
and sets theClip
to the resulting intersection. The specifiedShape
is transformed with the currentGraphics2D
Transform
before being intersected with the currentClip
. This method is used to make the currentClip
smaller. To make theClip
larger, usesetClip
. The user clip modified by this method is independent of the clipping associated with device bounds and visibility. If no clip has previously been set, or if the clip has been cleared usingsetClip
with anull
argument, the specifiedShape
becomes the new user clip.- Parameters:
s
- theShape
to be intersected with the currentClip
. Ifs
isnull
, this method clears the currentClip
.
-
getFontRenderContext
public abstract FontRenderContext getFontRenderContext()
Get the rendering context of theFont
within thisGraphics2D
context. TheFontRenderContext
encapsulates application hints such as anti-aliasing and fractional metrics, as well as target device specific information such as dots-per-inch. This information should be provided by the application when using objects that perform typographical formatting, such asFont
andTextLayout
. This information should also be provided by applications that perform their own layout and need accurate measurements of various characteristics of glyphs such as advance and line height when various rendering hints have been applied to the text rendering.- Returns:
- a reference to an instance of FontRenderContext.
- Since:
- 1.2
- See Also:
FontRenderContext
,Font.createGlyphVector(java.awt.font.FontRenderContext, java.lang.String)
,TextLayout
-
-
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