/* * @(#)Graphics2D.java 1.81 04/05/05 * * Copyright 2004 Sun Microsystems, Inc. All rights reserved. * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. */ package java.awt; import java.awt.RenderingHints.Key; import java.awt.geom.AffineTransform; import java.awt.image.ImageObserver; import java.awt.image.BufferedImageOp; import java.awt.image.BufferedImage; import java.awt.image.RenderedImage; import java.awt.image.renderable.RenderableImage; import java.awt.font.GlyphVector; import java.awt.font.FontRenderContext; import java.awt.font.TextAttribute; import java.text.AttributedCharacterIterator; import java.util.Map; /** * This Graphics2D class extends the * {@link Graphics} 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 a Graphics2D object are specified * in a device-independent coordinate system called User Space, which is * used by applications. The Graphics2D object contains * an {@link AffineTransform} 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, the Graphics2D 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. A * {@link GraphicsConfiguration} object defines the characteristics * of the rendering target, such as pixel format and resolution. * The same rendering target is used throughout the life of a * Graphics2D object. *

* When creating a Graphics2D object, the * GraphicsConfiguration * specifies the default transform for * the target of the Graphics2D (a * {@link Component} or {@link Image}). 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 the * Identity transform. * *

Rendering Process

* The Rendering Process can be broken down into four phases that are * controlled by the Graphics2D 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: *

    *
  1. * Determine what to render. *
  2. * Constrain the rendering operation to the current Clip. * The Clip is specified by a {@link Shape} in user * space and is controlled by the program using the various clip * manipulation methods of Graphics and * Graphics2D. This user clip * is transformed into device space by the current * Transform 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. *
  3. * Determine what colors to render. *
  4. * Apply the colors to the destination drawing surface using the current * {@link Composite} attribute in the Graphics2D context. *
*
* The three types of rendering operations, along with details of each * of their particular rendering processes are: *
    *
  1. * Shape operations *
      *
    1. * If the operation is a draw(Shape) operation, then * the {@link Stroke#createStrokedShape(Shape) createStrokedShape} * method on the current {@link Stroke} attribute in the * Graphics2D context is used to construct a new * Shape object that contains the outline of the specified * Shape. *
    2. * The Shape is transformed from user space to device space * using the current Transform * in the Graphics2D context. *
    3. * The outline of the Shape is extracted using the * {@link Shape#getPathIterator(AffineTransform) getPathIterator} method of * Shape, which returns a * {@link java.awt.geom.PathIterator PathIterator} * object that iterates along the boundary of the Shape. *
    4. * If the Graphics2D object cannot handle the curved segments * that the PathIterator object returns then it can call the * alternate * {@link Shape#getPathIterator(AffineTransform, double) getPathIterator} * method of Shape, which flattens the Shape. *
    5. * The current {@link Paint} in the Graphics2D context * is queried for a {@link PaintContext}, which specifies the * colors to render in device space. *
    *
  2. * Text operations *
      *
    1. * The following steps are used to determine the set of glyphs required * to render the indicated String: *
        *
      1. * If the argument is a String, then the current * Font in the Graphics2D context is asked to * convert the Unicode characters in the String into a set of * glyphs for presentation with whatever basic layout and shaping * algorithms the font implements. *
      2. * If the argument is an * {@link AttributedCharacterIterator}, * the iterator is asked to convert itself to a * {@link java.awt.font.TextLayout TextLayout} * using its embedded font attributes. The TextLayout * implements more sophisticated glyph layout algorithms that * perform Unicode bi-directional layout adjustments automatically * for multiple fonts of differing writing directions. *
      3. * If the argument is a * {@link GlyphVector}, then the * GlyphVector object already contains the appropriate * font-specific glyph codes with explicit coordinates for the position of * each glyph. *
      *
    2. * 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. *
    3. * The character outlines are filled as indicated above * under Shape operations. *
    4. * The current Paint is queried for a * PaintContext, which specifies * the colors to render in device space. *
    *
  3. * Image Operations *
      *
    1. * The region of interest is defined by the bounding box of the source * Image. * This bounding box is specified in Image Space, which is the * Image object's local coordinate system. *
    2. * If an AffineTransform is passed to * {@link #drawImage(java.awt.Image, java.awt.geom.AffineTransform, java.awt.image.ImageObserver) drawImage(Image, AffineTransform, ImageObserver)}, * the AffineTransform is used to transform the bounding * box from image space to user space. If no AffineTransform * is supplied, the bounding box is treated as if it is already in user space. *
    3. * The bounding box of the source Image is transformed from user * space into device space using the current Transform. * Note that the result of transforming the bounding box does not * necessarily result in a rectangular region in device space. *
    4. * The Image object determines what colors to render, * sampled according to the source to destination * coordinate mapping specified by the current Transform and the * optional image transform. *
    *
* *

Default Rendering Attributes

* The default values for the Graphics2D rendering attributes are: *
*
Paint *
The color of the Component. *
Font *
The Font of the Component. *
Stroke *
A square pen with a linewidth of 1, no dashing, miter segment joins * and square end caps. *
Transform *
The * {@link GraphicsConfiguration#getDefaultTransform() getDefaultTransform} * for the GraphicsConfiguration of the Component. *
Composite *
The {@link AlphaComposite#SRC_OVER} rule. *
Clip *
No rendering Clip, the output is clipped to the * Component. *
* *

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 * {@link RenderingHints#KEY_ANTIALIASING KEY_ANTIALIASING} hint key * to the * {@link RenderingHints#VALUE_ANTIALIAS_OFF VALUE_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 the * {@link RenderingHints#KEY_ANTIALIASING KEY_ANTIALIASING} hint * key to * {@link RenderingHints#VALUE_ANTIALIAS_ON VALUE_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 and * fill methods are defined, which clearly indicates * how Graphics2D extends Graphics based * on settings of Stroke and Transform * attributes and rendering hints. The definition * performs identically under default attribute settings. * For example, the default Stroke is a * BasicStroke 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. *

*

* The following definitions of general legacy methods * perform identically to previously specified behavior under default * attribute settings: *

* The Graphics class defines only the setColor * method to control the color to be painted. Since the Java 2D API extends * the Color object to implement the new Paint * interface, the existing * setColor method is now a convenience method for setting the * current Paint attribute to a Color object. * setColor(c) is equivalent to setPaint(c). *

* The Graphics class defines two methods for controlling * how colors are applied to the destination. *

    *
  1. * The setPaintMode method is implemented as a convenience * method to set the default Composite, equivalent to * setComposite(new AlphaComposite.SrcOver). *
  2. * The setXORMode(Color xorcolor) method is implemented * as a convenience method to set a special Composite object that * ignores the Alpha components of source colors and sets the * destination color to the value: *
     * dstpixel = (PixelOf(srccolor) ^ PixelOf(xorcolor) ^ dstpixel);
     * 
    *
* * @version 1.81, 05/05/04 * @author Jim Graham * @see java.awt.RenderingHints */ public abstract class Graphics2D extends Graphics { /** * Constructs a new Graphics2D object. Since * Graphics2D 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 another * Graphics2D object, created by a * Component, or obtained from images such as * {@link BufferedImage} objects. * @see java.awt.Component#getGraphics * @see java.awt.Graphics#create */ protected Graphics2D() { } /** * 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 * by height + 1 pixels tall. This method * uses the current Color exclusively and ignores * the current Paint. * @param x the x coordinate of the rectangle to be drawn. * @param y the y coordinate of the rectangle to be drawn. * @param width the width of the rectangle to be drawn. * @param height the height of the rectangle to be drawn. * @param raised a boolean that determines whether the rectangle * appears to be raised above the surface * or sunk into the surface. * @see java.awt.Graphics#fill3DRect */ public void draw3DRect(int x, int y, int width, int height, boolean raised) { Paint p = getPaint(); Color c = getColor(); Color brighter = c.brighter(); Color darker = c.darker(); setColor(raised ? brighter : darker); //drawLine(x, y, x, y + height); fillRect(x, y, 1, height + 1); //drawLine(x + 1, y, x + width - 1, y); fillRect(x + 1, y, width - 1, 1); setColor(raised ? darker : brighter); //drawLine(x + 1, y + height, x + width, y + height); fillRect(x + 1, y + height, width, 1); //drawLine(x + width, y, x + width, y + height - 1); fillRect(x + width, y, 1, height); setPaint(p); } /** * 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 current Color. This method uses * the current Color exclusively and ignores the current * Paint. * @param x the x coordinate of the rectangle to be filled. * @param y the y coordinate of the rectangle to be filled. * @param width the width of the rectangle to be filled. * @param height the height of the rectangle to be filled. * @param raised a boolean value that determines whether the * rectangle appears to be raised above the surface * or etched into the surface. * @see java.awt.Graphics#draw3DRect */ public void fill3DRect(int x, int y, int width, int height, boolean raised) { Paint p = getPaint(); Color c = getColor(); Color brighter = c.brighter(); Color darker = c.darker(); if (!raised) { setColor(darker); } else if (p != c) { setColor(c); } fillRect(x+1, y+1, width-2, height-2); setColor(raised ? brighter : darker); //drawLine(x, y, x, y + height - 1); fillRect(x, y, 1, height); //drawLine(x + 1, y, x + width - 2, y); fillRect(x + 1, y, width - 2, 1); setColor(raised ? darker : brighter); //drawLine(x + 1, y + height - 1, x + width - 1, y + height - 1); fillRect(x + 1, y + height - 1, width - 1, 1); //drawLine(x + width - 1, y, x + width - 1, y + height - 2); fillRect(x + width - 1, y, 1, height - 1); setPaint(p); } /** * Strokes the outline of a Shape using the settings of the * current Graphics2D context. The rendering attributes * applied include the Clip, Transform, * Paint, Composite and * Stroke attributes. * @param s the Shape to be rendered * @see #setStroke * @see #setPaint * @see java.awt.Graphics#setColor * @see #transform * @see #setTransform * @see #clip * @see #setClip * @see #setComposite */ public abstract void draw(Shape s); /** * 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 current Transform in the Graphics2D. * The specified transformation is applied to the image before the * transform attribute in the Graphics2D context is applied. * The rendering attributes applied include the Clip, * Transform, and Composite attributes. * Note that no rendering is done if the specified transform is * noninvertible. * @param img the specified image to be rendered. * This method does nothing if img is null. * @param xform the transformation from image space into user space * @param obs the {@link ImageObserver} * to be notified as more of the Image * is converted * @return true if the Image is * fully loaded and completely rendered, or if it's null; * false if the Image is still being loaded. * @see #transform * @see #setTransform * @see #setComposite * @see #clip * @see #setClip */ public abstract boolean drawImage(Image img, AffineTransform xform, ImageObserver obs); /** * Renders a BufferedImage that is * filtered with a * {@link BufferedImageOp}. * The rendering attributes applied include the Clip, * Transform * and Composite attributes. This is equivalent to: *

     * img1 = op.filter(img, null);
     * drawImage(img1, new AffineTransform(1f,0f,0f,1f,x,y), null);
     * 
* @param op the filter to be applied to the image before rendering * @param img the specified BufferedImage to be rendered. * This method does nothing if img is null. * @param x the x coordinate of the location in user space where * the upper left corner of the image is rendered * @param y the y coordinate of the location in user space where * the upper left corner of the image is rendered * * @see #transform * @see #setTransform * @see #setComposite * @see #clip * @see #setClip */ public abstract void drawImage(BufferedImage img, BufferedImageOp op, int x, int y); /** * Renders a {@link RenderedImage}, * applying a transform from image * space into user space before drawing. * The transformation from user space into device space is done with * the current Transform in the Graphics2D. * The specified transformation is applied to the image before the * transform attribute in the Graphics2D context is applied. * The rendering attributes applied include the Clip, * Transform, and Composite attributes. Note * that no rendering is done if the specified transform is * noninvertible. * @param img the image to be rendered. This method does * nothing if img is null. * @param xform the transformation from image space into user space * @see #transform * @see #setTransform * @see #setComposite * @see #clip * @see #setClip */ public abstract void drawRenderedImage(RenderedImage img, AffineTransform xform); /** * Renders a * {@link RenderableImage}, * applying a transform from image space into user space before drawing. * The transformation from user space into device space is done with * the current Transform in the Graphics2D. * The specified transformation is applied to the image before the * transform attribute in the Graphics2D context is applied. * The rendering attributes applied include the Clip, * Transform, and Composite 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 the RenderableImage. * If explicit control is required over specific hints recognized by a * specific RenderableImage, or if knowledge of which hints * are used is required, then a RenderedImage should be * obtained directly from the RenderableImage * and rendered using *{@link #drawRenderedImage(RenderedImage, AffineTransform) drawRenderedImage}. * @param img the image to be rendered. This method does * nothing if img is null. * @param xform the transformation from image space into user space * @see #transform * @see #setTransform * @see #setComposite * @see #clip * @see #setClip * @see #drawRenderedImage */ public abstract void drawRenderableImage(RenderableImage img, AffineTransform xform); /** * Renders the text of the specified String, using the * current text attribute state in the Graphics2D context. * The baseline of the * first character is at position (xy) in * the User Space. * The rendering attributes applied include the Clip, * Transform, Paint, Font and * Composite 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. * @param str the string to be rendered * @param x the x coordinate of the location where the * String should be rendered * @param y the y coordinate of the location where the * String should be rendered * @throws NullPointerException if str is * null * @see java.awt.Graphics#drawBytes * @see java.awt.Graphics#drawChars * @since JDK1.0 */ public abstract void drawString(String str, int x, int y); /** * Renders the text specified by the specified String, * using the current text attribute state in the Graphics2D context. * The baseline of the first character is at position * (xy) in the User Space. * The rendering attributes applied include the Clip, * Transform, Paint, Font and * Composite 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. * @param s the String to be rendered * @param x the x coordinate of the location where the * String should be rendered * @param y the y coordinate of the location where the * String should be rendered * @throws NullPointerException if str is * null * @see #setPaint * @see java.awt.Graphics#setColor * @see java.awt.Graphics#setFont * @see #setTransform * @see #setComposite * @see #setClip */ public abstract void drawString(String s, float x, float y); /** * Renders the text of the specified iterator, using the * Graphics2D context's current Paint. The * iterator has to specify a font * for each character. The baseline of the * first character is at position (xy) in the * User Space. * The rendering attributes applied include the Clip, * Transform, Paint, and * Composite 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. * @param iterator the iterator whose text is to be rendered * @param x the x coordinate where the iterator's text is to be * rendered * @param y the y coordinate where the iterator's text is to be * rendered * @see #setPaint * @see java.awt.Graphics#setColor * @see #setTransform * @see #setComposite * @see #setClip */ public abstract void drawString(AttributedCharacterIterator iterator, int x, int y); /** * Renders the text of the specified iterator, using the * Graphics2D context's current Paint. The * iterator must specify a font * for each character. The baseline of the * first character is at position (xy) in the * User Space. * The rendering attributes applied include the Clip, * Transform, Paint, and * Composite 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. * @param iterator the iterator whose text is to be rendered * @param x the x coordinate where the iterator's text is to be * rendered * @param y the y coordinate where the iterator's text is to be * rendered * @see #setPaint * @see java.awt.Graphics#setColor * @see #setTransform * @see #setComposite * @see #setClip */ public abstract void drawString(AttributedCharacterIterator iterator, float x, float y); /** * Renders the text of the specified * {@link GlyphVector} using * the Graphics2D context's rendering attributes. * The rendering attributes applied include the Clip, * Transform, Paint, and * Composite attributes. The GlyphVector * specifies individual glyphs from a {@link Font}. * The GlyphVector can also contain the glyph positions. * This is the fastest way to render a set of characters to the * screen. * @param g the GlyphVector to be rendered * @param x the x position in User Space where the glyphs should * be rendered * @param y the y position in User Space where the glyphs should * be rendered * * @see java.awt.Font#createGlyphVector * @see java.awt.font.GlyphVector * @see #setPaint * @see java.awt.Graphics#setColor * @see #setTransform * @see #setComposite * @see #setClip */ public abstract void drawGlyphVector(GlyphVector g, float x, float y); /** * Fills the interior of a Shape using the settings of the * Graphics2D context. The rendering attributes applied * include the Clip, Transform, * Paint, and Composite. * @param s the Shape to be filled * @see #setPaint * @see java.awt.Graphics#setColor * @see #transform * @see #setTransform * @see #setComposite * @see #clip * @see #setClip */ public abstract void fill(Shape s); /** * Checks whether or not the specified Shape intersects * the specified {@link Rectangle}, which is in device * space. If onStroke is false, this method checks * whether or not the interior of the specified Shape * intersects the specified Rectangle. If * onStroke is true, this method checks * whether or not the Stroke of the specified * Shape outline intersects the specified * Rectangle. * The rendering attributes taken into account include the * Clip, Transform, and Stroke * attributes. * @param rect the area in device space to check for a hit * @param s the Shape to check for a hit * @param onStroke flag used to choose between testing the * stroked or the filled shape. If the flag is true, the * Stroke oultine is tested. If the flag is * false, the filled Shape is tested. * @return true if there is a hit; false * otherwise. * @see #setStroke * @see #fill * @see #draw * @see #transform * @see #setTransform * @see #clip * @see #setClip */ public abstract boolean hit(Rectangle rect, Shape s, boolean onStroke); /** * Returns the device configuration associated with this * Graphics2D. * @return the device configuration of this Graphics2D. */ public abstract GraphicsConfiguration getDeviceConfiguration(); /** * Sets the Composite for the Graphics2D context. * The Composite is used in all drawing methods such as * drawImage, drawString, draw, * and fill. 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 a * Component on the display screen and the * Composite is a custom object rather than an * instance of the AlphaComposite class, and if * there is a security manager, its checkPermission * method is called with an AWTPermission("readDisplayPixels") * permission. * @throws SecurityException * if a custom Composite object is being * used to render to the screen and a security manager * is set and its checkPermission method * does not allow the operation. * @param comp the Composite object to be used for rendering * @see java.awt.Graphics#setXORMode * @see java.awt.Graphics#setPaintMode * @see #getComposite * @see AlphaComposite * @see SecurityManager#checkPermission * @see java.awt.AWTPermission */ public abstract void setComposite(Composite comp); /** * Sets the Paint attribute for the * Graphics2D context. Calling this method * with a null Paint object does * not have any effect on the current Paint attribute * of this Graphics2D. * @param paint the Paint object to be used to generate * color during the rendering process, or null * @see java.awt.Graphics#setColor * @see #getPaint * @see GradientPaint * @see TexturePaint */ public abstract void setPaint( Paint paint ); /** * Sets the Stroke for the Graphics2D context. * @param s the Stroke object to be used to stroke a * Shape during the rendering process * @see BasicStroke * @see #getStroke */ public abstract void setStroke(Stroke s); /** * 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 the * RenderingHints class for definitions of some common * keys and values. * @param hintKey the key of the hint to be set. * @param hintValue the value indicating preferences for the specified * hint category. * @see #getRenderingHint(RenderingHints.Key) * @see RenderingHints */ public abstract void setRenderingHint(Key hintKey, Object hintValue); /** * 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 the * RenderingHints class for definitions of some common * keys and values. * @param hintKey the key corresponding to the hint to get. * @return 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 RenderingHints * @see #setRenderingHint(RenderingHints.Key, Object) */ public abstract Object getRenderingHint(Key hintKey); /** * Replaces the values of all preferences for the rendering * algorithms with the specified hints. * The existing values for all rendering hints are discarded and * the new set of known hints and values are initialized from the * specified {@link Map} object. * Hint categories include controls for rendering quality and * overall time/quality trade-off in the rendering process. * Refer to the RenderingHints class for definitions of * some common keys and values. * @param hints the rendering hints to be set * @see #getRenderingHints * @see RenderingHints */ public abstract void setRenderingHints(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 * specified Map 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 the RenderingHints class for definitions of * some common keys and values. * @param hints the rendering hints to be set * @see RenderingHints */ public abstract void addRenderingHints(Map hints); /** * 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 the * RenderingHints class for definitions of some common * keys and values. * @return a reference to an instance of RenderingHints * that contains the current preferences. * @see RenderingHints * @see #setRenderingHints(Map) */ public abstract RenderingHints getRenderingHints(); /** * Translates the origin of the Graphics2D context to the * point (xy) in the current coordinate system. * Modifies the Graphics2D context so that its new origin * corresponds to the point (xy) in the * Graphics2D context's former coordinate system. All * coordinates used in subsequent rendering operations on this graphics * context are relative to this new origin. * @param x the specified x coordinate * @param y the specified y coordinate * @since JDK1.0 */ public abstract void translate(int x, int y); /** * Concatenates the current * Graphics2D 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 an * AffineTransform represented by the following matrix: *

     *		[   1    0    tx  ]
     *		[   0    1    ty  ]
     *		[   0    0    1   ]
     * 
* @param tx the distance to translate along the x-axis * @param ty the distance to translate along the y-axis */ public abstract void translate(double tx, double ty); /** * Concatenates the current Graphics2D * Transform with a rotation transform. * Subsequent rendering is rotated by the specified radians relative * to the previous origin. * This is equivalent to calling transform(R), where R is an * AffineTransform 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. * @param theta the angle of rotation in radians */ public abstract void rotate(double theta); /** * Concatenates the current Graphics2D * 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. * @param theta the angle of rotation in radians * @param x the x coordinate of the origin of the rotation * @param y the y coordinate of the origin of the rotation */ public abstract void rotate(double theta, double x, double y); /** * Concatenates the current Graphics2D * Transform with a scaling transformation * Subsequent rendering is resized according to the specified scaling * factors relative to the previous scaling. * This is equivalent to calling transform(S), where S is an * AffineTransform represented by the following matrix: *
     *		[   sx   0    0   ]
     *		[   0    sy   0   ]
     *		[   0    0    1   ]
     * 
* @param sx the amount by which X coordinates in subsequent * rendering operations are multiplied relative to previous * rendering operations. * @param sy the amount by which Y coordinates in subsequent * rendering operations are multiplied relative to previous * rendering operations. */ public abstract void scale(double sx, double sy); /** * Concatenates the current Graphics2D * Transform with a shearing transform. * Subsequent renderings are sheared by the specified * multiplier relative to the previous position. * This is equivalent to calling transform(SH), where SH * is an AffineTransform represented by the following * matrix: *
     *		[   1   shx   0   ]
     *		[  shy   1    0   ]
     *		[   0    0    1   ]
     * 
* @param shx the multiplier by which coordinates are shifted in * the positive X axis direction as a function of their Y coordinate * @param shy the multiplier by which coordinates are shifted in * the positive Y axis direction as a function of their X coordinate */ public abstract void shear(double shx, double shy); /** * Composes an AffineTransform object with the * Transform in this Graphics2D according * to the rule last-specified-first-applied. If the current * Transform is Cx, the result of composition * with Tx is a new Transform Cx'. Cx' becomes the * current Transform for this Graphics2D. * Transforming a point p by the updated Transform Cx' is * equivalent to first transforming p by Tx and then transforming * the result by the original Transform 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. * @param Tx the AffineTransform object to be composed with * the current Transform * @see #setTransform * @see AffineTransform */ public abstract void transform(AffineTransform Tx); /** * Overwrites the Transform in the Graphics2D context. * WARNING: This method should never be used to apply a new * coordinate transform on top of an existing transform because the * Graphics2D 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, * or shear methods. The setTransform * method is intended only for restoring the original * Graphics2D 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); *
* * @param Tx the AffineTransform that was retrieved * from the getTransform method * @see #transform * @see #getTransform * @see AffineTransform */ public abstract void setTransform(AffineTransform Tx); /** * Returns a copy of the current Transform in the * Graphics2D context. * @return the current AffineTransform in the * Graphics2D context. * @see #transform * @see #setTransform */ public abstract AffineTransform getTransform(); /** * Returns the current Paint of the * Graphics2D context. * @return the current Graphics2D Paint, * which defines a color or pattern. * @see #setPaint * @see java.awt.Graphics#setColor */ public abstract Paint getPaint(); /** * Returns the current Composite in the * Graphics2D context. * @return the current Graphics2D Composite, * which defines a compositing style. * @see #setComposite */ public abstract Composite getComposite(); /** * Sets the background color for the Graphics2D context. * The background color is used for clearing a region. * When a Graphics2D is constructed for a * Component, the background color is * inherited from the Component. Setting the background color * in the Graphics2D context only affects the subsequent * clearRect calls and not the background color of the * Component. To change the background * of the Component, use appropriate methods of * the Component. * @param color the background color that isused in * subsequent calls to clearRect * @see #getBackground * @see java.awt.Graphics#clearRect */ public abstract void setBackground(Color color); /** * Returns the background color used for clearing a region. * @return the current Graphics2D Color, * which defines the background color. * @see #setBackground */ public abstract Color getBackground(); /** * Returns the current Stroke in the * Graphics2D context. * @return the current Graphics2D Stroke, * which defines the line style. * @see #setStroke */ public abstract Stroke getStroke(); /** * Intersects the current Clip with the interior of the * specified Shape and sets the Clip to the * resulting intersection. The specified Shape is * transformed with the current Graphics2D * Transform before being intersected with the current * Clip. This method is used to make the current * Clip smaller. * To make the Clip larger, use setClip. * 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 using * {@link Graphics#setClip(Shape) setClip} with a null * argument, the specified Shape becomes the new * user clip. * @param s the Shape to be intersected with the current * Clip. If s is null, * this method clears the current Clip. */ public abstract void clip(Shape s); /** * Get the rendering context of the Font within this * Graphics2D context. * The {@link FontRenderContext} * 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 as Font and * TextLayout. 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. * * @return a reference to an instance of FontRenderContext. * @see java.awt.font.FontRenderContext * @see java.awt.Font#createGlyphVector * @see java.awt.font.TextLayout * @since 1.2 */ public abstract FontRenderContext getFontRenderContext(); }