| /* |
| * Copyright (c) 1995, 2006, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package java.awt; |
| |
| import java.io.*; |
| import java.lang.*; |
| import java.util.*; |
| import java.awt.image.ImageObserver; |
| import java.text.AttributedCharacterIterator; |
| |
| /** |
| * The <code>Graphics</code> class is the abstract base class for |
| * all graphics contexts that allow an application to draw onto |
| * components that are realized on various devices, as well as |
| * onto off-screen images. |
| * <p> |
| * A <code>Graphics</code> object encapsulates state information needed |
| * for the basic rendering operations that Java supports. This |
| * state information includes the following properties: |
| * <p> |
| * <ul> |
| * <li>The <code>Component</code> object on which to draw. |
| * <li>A translation origin for rendering and clipping coordinates. |
| * <li>The current clip. |
| * <li>The current color. |
| * <li>The current font. |
| * <li>The current logical pixel operation function (XOR or Paint). |
| * <li>The current XOR alternation color |
| * (see {@link Graphics#setXORMode}). |
| * </ul> |
| * <p> |
| * Coordinates are infinitely thin and lie between the pixels of the |
| * output device. |
| * Operations that draw the outline of a figure operate by traversing |
| * an infinitely thin path between pixels with a pixel-sized pen that hangs |
| * down and to the right of the anchor point on the path. |
| * Operations that fill a figure operate by filling the interior |
| * of that infinitely thin path. |
| * Operations that render horizontal text render the ascending |
| * portion of character glyphs entirely above the baseline coordinate. |
| * <p> |
| * The graphics pen hangs down and to the right from the path it traverses. |
| * This has the following implications: |
| * <p><ul> |
| * <li>If you draw a figure that covers a given rectangle, that |
| * figure occupies one extra row of pixels on the right and bottom edges |
| * as compared to filling a figure that is bounded by that same rectangle. |
| * <li>If you draw a horizontal line along the same <i>y</i> coordinate as |
| * the baseline of a line of text, that line is drawn entirely below |
| * the text, except for any descenders. |
| * </ul><p> |
| * All coordinates that appear as arguments to the methods of this |
| * <code>Graphics</code> object are considered relative to the |
| * translation origin of this <code>Graphics</code> object prior to |
| * the invocation of the method. |
| * <p> |
| * All rendering operations modify only pixels which lie within the |
| * area bounded by the current clip, which is specified by a {@link Shape} |
| * in user space and is controlled by the program using the |
| * <code>Graphics</code> object. This <i>user clip</i> |
| * is transformed into device space and combined with the |
| * <i>device clip</i>, which is defined by the visibility of windows and |
| * device extents. The combination of the user clip and device clip |
| * defines the <i>composite clip</i>, which determines the final clipping |
| * region. The user clip cannot be modified by the rendering |
| * system to reflect the resulting composite clip. The user clip can only |
| * be changed through the <code>setClip</code> or <code>clipRect</code> |
| * methods. |
| * All drawing or writing is done in the current color, |
| * using the current paint mode, and in the current font. |
| * |
| * @author Sami Shaio |
| * @author Arthur van Hoff |
| * @see java.awt.Component |
| * @see java.awt.Graphics#clipRect(int, int, int, int) |
| * @see java.awt.Graphics#setColor(java.awt.Color) |
| * @see java.awt.Graphics#setPaintMode() |
| * @see java.awt.Graphics#setXORMode(java.awt.Color) |
| * @see java.awt.Graphics#setFont(java.awt.Font) |
| * @since JDK1.0 |
| */ |
| public abstract class Graphics { |
| |
| /** |
| * Constructs a new <code>Graphics</code> object. |
| * This constructor is the default contructor for a graphics |
| * context. |
| * <p> |
| * Since <code>Graphics</code> is an abstract class, applications |
| * cannot call this constructor directly. Graphics contexts are |
| * obtained from other graphics contexts or are created by calling |
| * <code>getGraphics</code> on a component. |
| * @see java.awt.Graphics#create() |
| * @see java.awt.Component#getGraphics |
| */ |
| protected Graphics() { |
| } |
| |
| /** |
| * Creates a new <code>Graphics</code> object that is |
| * a copy of this <code>Graphics</code> object. |
| * @return a new graphics context that is a copy of |
| * this graphics context. |
| */ |
| public abstract Graphics create(); |
| |
| /** |
| * Creates a new <code>Graphics</code> object based on this |
| * <code>Graphics</code> object, but with a new translation and clip area. |
| * The new <code>Graphics</code> object has its origin |
| * translated to the specified point (<i>x</i>, <i>y</i>). |
| * Its clip area is determined by the intersection of the original |
| * clip area with the specified rectangle. The arguments are all |
| * interpreted in the coordinate system of the original |
| * <code>Graphics</code> object. The new graphics context is |
| * identical to the original, except in two respects: |
| * <p> |
| * <ul> |
| * <li> |
| * The new graphics context is translated by (<i>x</i>, <i>y</i>). |
| * That is to say, the point (<code>0</code>, <code>0</code>) in the |
| * new graphics context is the same as (<i>x</i>, <i>y</i>) in |
| * the original graphics context. |
| * <li> |
| * The new graphics context has an additional clipping rectangle, in |
| * addition to whatever (translated) clipping rectangle it inherited |
| * from the original graphics context. The origin of the new clipping |
| * rectangle is at (<code>0</code>, <code>0</code>), and its size |
| * is specified by the <code>width</code> and <code>height</code> |
| * arguments. |
| * </ul> |
| * <p> |
| * @param x the <i>x</i> coordinate. |
| * @param y the <i>y</i> coordinate. |
| * @param width the width of the clipping rectangle. |
| * @param height the height of the clipping rectangle. |
| * @return a new graphics context. |
| * @see java.awt.Graphics#translate |
| * @see java.awt.Graphics#clipRect |
| */ |
| public Graphics create(int x, int y, int width, int height) { |
| Graphics g = create(); |
| if (g == null) return null; |
| g.translate(x, y); |
| g.clipRect(0, 0, width, height); |
| return g; |
| } |
| |
| /** |
| * Translates the origin of the graphics context to the point |
| * (<i>x</i>, <i>y</i>) in the current coordinate system. |
| * Modifies this graphics context so that its new origin corresponds |
| * to the point (<i>x</i>, <i>y</i>) in this graphics context's |
| * original coordinate system. All coordinates used in subsequent |
| * rendering operations on this graphics context will be relative |
| * to this new origin. |
| * @param x the <i>x</i> coordinate. |
| * @param y the <i>y</i> coordinate. |
| */ |
| public abstract void translate(int x, int y); |
| |
| /** |
| * Gets this graphics context's current color. |
| * @return this graphics context's current color. |
| * @see java.awt.Color |
| * @see java.awt.Graphics#setColor(Color) |
| */ |
| public abstract Color getColor(); |
| |
| /** |
| * Sets this graphics context's current color to the specified |
| * color. All subsequent graphics operations using this graphics |
| * context use this specified color. |
| * @param c the new rendering color. |
| * @see java.awt.Color |
| * @see java.awt.Graphics#getColor |
| */ |
| public abstract void setColor(Color c); |
| |
| /** |
| * Sets the paint mode of this graphics context to overwrite the |
| * destination with this graphics context's current color. |
| * This sets the logical pixel operation function to the paint or |
| * overwrite mode. All subsequent rendering operations will |
| * overwrite the destination with the current color. |
| */ |
| public abstract void setPaintMode(); |
| |
| /** |
| * Sets the paint mode of this graphics context to alternate between |
| * this graphics context's current color and the new specified color. |
| * This specifies that logical pixel operations are performed in the |
| * XOR mode, which alternates pixels between the current color and |
| * a specified XOR color. |
| * <p> |
| * When drawing operations are performed, pixels which are the |
| * current color are changed to the specified color, and vice versa. |
| * <p> |
| * Pixels that are of colors other than those two colors are changed |
| * in an unpredictable but reversible manner; if the same figure is |
| * drawn twice, then all pixels are restored to their original values. |
| * @param c1 the XOR alternation color |
| */ |
| public abstract void setXORMode(Color c1); |
| |
| /** |
| * Gets the current font. |
| * @return this graphics context's current font. |
| * @see java.awt.Font |
| * @see java.awt.Graphics#setFont(Font) |
| */ |
| public abstract Font getFont(); |
| |
| /** |
| * Sets this graphics context's font to the specified font. |
| * All subsequent text operations using this graphics context |
| * use this font. A null argument is silently ignored. |
| * @param font the font. |
| * @see java.awt.Graphics#getFont |
| * @see java.awt.Graphics#drawString(java.lang.String, int, int) |
| * @see java.awt.Graphics#drawBytes(byte[], int, int, int, int) |
| * @see java.awt.Graphics#drawChars(char[], int, int, int, int) |
| */ |
| public abstract void setFont(Font font); |
| |
| /** |
| * Gets the font metrics of the current font. |
| * @return the font metrics of this graphics |
| * context's current font. |
| * @see java.awt.Graphics#getFont |
| * @see java.awt.FontMetrics |
| * @see java.awt.Graphics#getFontMetrics(Font) |
| */ |
| public FontMetrics getFontMetrics() { |
| return getFontMetrics(getFont()); |
| } |
| |
| /** |
| * Gets the font metrics for the specified font. |
| * @return the font metrics for the specified font. |
| * @param f the specified font |
| * @see java.awt.Graphics#getFont |
| * @see java.awt.FontMetrics |
| * @see java.awt.Graphics#getFontMetrics() |
| */ |
| public abstract FontMetrics getFontMetrics(Font f); |
| |
| |
| /** |
| * Returns the bounding rectangle of the current clipping area. |
| * This method refers to the user clip, which is independent of the |
| * clipping associated with device bounds and window visibility. |
| * If no clip has previously been set, or if the clip has been |
| * cleared using <code>setClip(null)</code>, this method returns |
| * <code>null</code>. |
| * The coordinates in the rectangle are relative to the coordinate |
| * system origin of this graphics context. |
| * @return the bounding rectangle of the current clipping area, |
| * or <code>null</code> if no clip is set. |
| * @see java.awt.Graphics#getClip |
| * @see java.awt.Graphics#clipRect |
| * @see java.awt.Graphics#setClip(int, int, int, int) |
| * @see java.awt.Graphics#setClip(Shape) |
| * @since JDK1.1 |
| */ |
| public abstract Rectangle getClipBounds(); |
| |
| /** |
| * Intersects the current clip with the specified rectangle. |
| * The resulting clipping area is the intersection of the current |
| * clipping area and the specified rectangle. If there is no |
| * current clipping area, either because the clip has never been |
| * set, or the clip has been cleared using <code>setClip(null)</code>, |
| * the specified rectangle becomes the new clip. |
| * This method sets the user clip, which is independent of the |
| * clipping associated with device bounds and window visibility. |
| * This method can only be used to make the current clip smaller. |
| * To set the current clip larger, use any of the setClip methods. |
| * Rendering operations have no effect outside of the clipping area. |
| * @param x the x coordinate of the rectangle to intersect the clip with |
| * @param y the y coordinate of the rectangle to intersect the clip with |
| * @param width the width of the rectangle to intersect the clip with |
| * @param height the height of the rectangle to intersect the clip with |
| * @see #setClip(int, int, int, int) |
| * @see #setClip(Shape) |
| */ |
| public abstract void clipRect(int x, int y, int width, int height); |
| |
| /** |
| * Sets the current clip to the rectangle specified by the given |
| * coordinates. This method sets the user clip, which is |
| * independent of the clipping associated with device bounds |
| * and window visibility. |
| * Rendering operations have no effect outside of the clipping area. |
| * @param x the <i>x</i> coordinate of the new clip rectangle. |
| * @param y the <i>y</i> coordinate of the new clip rectangle. |
| * @param width the width of the new clip rectangle. |
| * @param height the height of the new clip rectangle. |
| * @see java.awt.Graphics#clipRect |
| * @see java.awt.Graphics#setClip(Shape) |
| * @see java.awt.Graphics#getClip |
| * @since JDK1.1 |
| */ |
| public abstract void setClip(int x, int y, int width, int height); |
| |
| /** |
| * Gets the current clipping area. |
| * This method returns the user clip, which is independent of the |
| * clipping associated with device bounds and window visibility. |
| * If no clip has previously been set, or if the clip has been |
| * cleared using <code>setClip(null)</code>, this method returns |
| * <code>null</code>. |
| * @return a <code>Shape</code> object representing the |
| * current clipping area, or <code>null</code> if |
| * no clip is set. |
| * @see java.awt.Graphics#getClipBounds |
| * @see java.awt.Graphics#clipRect |
| * @see java.awt.Graphics#setClip(int, int, int, int) |
| * @see java.awt.Graphics#setClip(Shape) |
| * @since JDK1.1 |
| */ |
| public abstract Shape getClip(); |
| |
| /** |
| * Sets the current clipping area to an arbitrary clip shape. |
| * Not all objects that implement the <code>Shape</code> |
| * interface can be used to set the clip. The only |
| * <code>Shape</code> objects that are guaranteed to be |
| * supported are <code>Shape</code> objects that are |
| * obtained via the <code>getClip</code> method and via |
| * <code>Rectangle</code> objects. This method sets the |
| * user clip, which is independent of the clipping associated |
| * with device bounds and window visibility. |
| * @param clip the <code>Shape</code> to use to set the clip |
| * @see java.awt.Graphics#getClip() |
| * @see java.awt.Graphics#clipRect |
| * @see java.awt.Graphics#setClip(int, int, int, int) |
| * @since JDK1.1 |
| */ |
| public abstract void setClip(Shape clip); |
| |
| /** |
| * Copies an area of the component by a distance specified by |
| * <code>dx</code> and <code>dy</code>. From the point specified |
| * by <code>x</code> and <code>y</code>, this method |
| * copies downwards and to the right. To copy an area of the |
| * component to the left or upwards, specify a negative value for |
| * <code>dx</code> or <code>dy</code>. |
| * If a portion of the source rectangle lies outside the bounds |
| * of the component, or is obscured by another window or component, |
| * <code>copyArea</code> will be unable to copy the associated |
| * pixels. The area that is omitted can be refreshed by calling |
| * the component's <code>paint</code> method. |
| * @param x the <i>x</i> coordinate of the source rectangle. |
| * @param y the <i>y</i> coordinate of the source rectangle. |
| * @param width the width of the source rectangle. |
| * @param height the height of the source rectangle. |
| * @param dx the horizontal distance to copy the pixels. |
| * @param dy the vertical distance to copy the pixels. |
| */ |
| public abstract void copyArea(int x, int y, int width, int height, |
| int dx, int dy); |
| |
| /** |
| * Draws a line, using the current color, between the points |
| * <code>(x1, y1)</code> and <code>(x2, y2)</code> |
| * in this graphics context's coordinate system. |
| * @param x1 the first point's <i>x</i> coordinate. |
| * @param y1 the first point's <i>y</i> coordinate. |
| * @param x2 the second point's <i>x</i> coordinate. |
| * @param y2 the second point's <i>y</i> coordinate. |
| */ |
| public abstract void drawLine(int x1, int y1, int x2, int y2); |
| |
| /** |
| * Fills the specified rectangle. |
| * The left and right edges of the rectangle are at |
| * <code>x</code> and <code>x + width - 1</code>. |
| * The top and bottom edges are at |
| * <code>y</code> and <code>y + height - 1</code>. |
| * The resulting rectangle covers an area |
| * <code>width</code> pixels wide by |
| * <code>height</code> pixels tall. |
| * The rectangle is filled using the graphics context's current color. |
| * @param x the <i>x</i> coordinate |
| * of the rectangle to be filled. |
| * @param y the <i>y</i> 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. |
| * @see java.awt.Graphics#clearRect |
| * @see java.awt.Graphics#drawRect |
| */ |
| public abstract void fillRect(int x, int y, int width, int height); |
| |
| /** |
| * Draws the outline of the specified rectangle. |
| * The left and right edges of the rectangle are at |
| * <code>x</code> and <code>x + width</code>. |
| * The top and bottom edges are at |
| * <code>y</code> and <code>y + height</code>. |
| * The rectangle is drawn using the graphics context's current color. |
| * @param x the <i>x</i> coordinate |
| * of the rectangle to be drawn. |
| * @param y the <i>y</i> 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. |
| * @see java.awt.Graphics#fillRect |
| * @see java.awt.Graphics#clearRect |
| */ |
| public void drawRect(int x, int y, int width, int height) { |
| if ((width < 0) || (height < 0)) { |
| return; |
| } |
| |
| if (height == 0 || width == 0) { |
| drawLine(x, y, x + width, y + height); |
| } else { |
| drawLine(x, y, x + width - 1, y); |
| drawLine(x + width, y, x + width, y + height - 1); |
| drawLine(x + width, y + height, x + 1, y + height); |
| drawLine(x, y + height, x, y + 1); |
| } |
| } |
| |
| /** |
| * Clears the specified rectangle by filling it with the background |
| * color of the current drawing surface. This operation does not |
| * use the current paint mode. |
| * <p> |
| * Beginning with Java 1.1, the background color |
| * of offscreen images may be system dependent. Applications should |
| * use <code>setColor</code> followed by <code>fillRect</code> to |
| * ensure that an offscreen image is cleared to a specific color. |
| * @param x the <i>x</i> coordinate of the rectangle to clear. |
| * @param y the <i>y</i> coordinate of the rectangle to clear. |
| * @param width the width of the rectangle to clear. |
| * @param height the height of the rectangle to clear. |
| * @see java.awt.Graphics#fillRect(int, int, int, int) |
| * @see java.awt.Graphics#drawRect |
| * @see java.awt.Graphics#setColor(java.awt.Color) |
| * @see java.awt.Graphics#setPaintMode |
| * @see java.awt.Graphics#setXORMode(java.awt.Color) |
| */ |
| public abstract void clearRect(int x, int y, int width, int height); |
| |
| /** |
| * Draws an outlined round-cornered rectangle using this graphics |
| * context's current color. The left and right edges of the rectangle |
| * are at <code>x</code> and <code>x + width</code>, |
| * respectively. The top and bottom edges of the rectangle are at |
| * <code>y</code> and <code>y + height</code>. |
| * @param x the <i>x</i> coordinate of the rectangle to be drawn. |
| * @param y the <i>y</i> 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 arcWidth the horizontal diameter of the arc |
| * at the four corners. |
| * @param arcHeight the vertical diameter of the arc |
| * at the four corners. |
| * @see java.awt.Graphics#fillRoundRect |
| */ |
| public abstract void drawRoundRect(int x, int y, int width, int height, |
| int arcWidth, int arcHeight); |
| |
| /** |
| * Fills the specified rounded corner rectangle with the current color. |
| * The left and right edges of the rectangle |
| * are at <code>x</code> and <code>x + width - 1</code>, |
| * respectively. The top and bottom edges of the rectangle are at |
| * <code>y</code> and <code>y + height - 1</code>. |
| * @param x the <i>x</i> coordinate of the rectangle to be filled. |
| * @param y the <i>y</i> 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 arcWidth the horizontal diameter |
| * of the arc at the four corners. |
| * @param arcHeight the vertical diameter |
| * of the arc at the four corners. |
| * @see java.awt.Graphics#drawRoundRect |
| */ |
| public abstract void fillRoundRect(int x, int y, int width, int height, |
| int arcWidth, int arcHeight); |
| |
| /** |
| * 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. |
| * <p> |
| * The colors used for the highlighting effect are determined |
| * based on the current color. |
| * The resulting rectangle covers an area that is |
| * <code>width + 1</code> pixels wide |
| * by <code>height + 1</code> pixels tall. |
| * @param x the <i>x</i> coordinate of the rectangle to be drawn. |
| * @param y the <i>y</i> 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) { |
| Color c = getColor(); |
| Color brighter = c.brighter(); |
| Color darker = c.darker(); |
| |
| setColor(raised ? brighter : darker); |
| drawLine(x, y, x, y + height); |
| drawLine(x + 1, y, x + width - 1, y); |
| setColor(raised ? darker : brighter); |
| drawLine(x + 1, y + height, x + width, y + height); |
| drawLine(x + width, y, x + width, y + height - 1); |
| setColor(c); |
| } |
| |
| /** |
| * Paints a 3-D highlighted rectangle filled with the current color. |
| * The edges of the rectangle will be 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 will be determined from |
| * the current color. |
| * @param x the <i>x</i> coordinate of the rectangle to be filled. |
| * @param y the <i>y</i> 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) { |
| Color c = getColor(); |
| Color brighter = c.brighter(); |
| Color darker = c.darker(); |
| |
| if (!raised) { |
| setColor(darker); |
| } |
| fillRect(x+1, y+1, width-2, height-2); |
| setColor(raised ? brighter : darker); |
| drawLine(x, y, x, y + height - 1); |
| drawLine(x + 1, y, x + width - 2, y); |
| setColor(raised ? darker : brighter); |
| drawLine(x + 1, y + height - 1, x + width - 1, y + height - 1); |
| drawLine(x + width - 1, y, x + width - 1, y + height - 2); |
| setColor(c); |
| } |
| |
| /** |
| * Draws the outline of an oval. |
| * The result is a circle or ellipse that fits within the |
| * rectangle specified by the <code>x</code>, <code>y</code>, |
| * <code>width</code>, and <code>height</code> arguments. |
| * <p> |
| * The oval covers an area that is |
| * <code>width + 1</code> pixels wide |
| * and <code>height + 1</code> pixels tall. |
| * @param x the <i>x</i> coordinate of the upper left |
| * corner of the oval to be drawn. |
| * @param y the <i>y</i> coordinate of the upper left |
| * corner of the oval to be drawn. |
| * @param width the width of the oval to be drawn. |
| * @param height the height of the oval to be drawn. |
| * @see java.awt.Graphics#fillOval |
| */ |
| public abstract void drawOval(int x, int y, int width, int height); |
| |
| /** |
| * Fills an oval bounded by the specified rectangle with the |
| * current color. |
| * @param x the <i>x</i> coordinate of the upper left corner |
| * of the oval to be filled. |
| * @param y the <i>y</i> coordinate of the upper left corner |
| * of the oval to be filled. |
| * @param width the width of the oval to be filled. |
| * @param height the height of the oval to be filled. |
| * @see java.awt.Graphics#drawOval |
| */ |
| public abstract void fillOval(int x, int y, int width, int height); |
| |
| /** |
| * Draws the outline of a circular or elliptical arc |
| * covering the specified rectangle. |
| * <p> |
| * The resulting arc begins at <code>startAngle</code> and extends |
| * for <code>arcAngle</code> degrees, using the current color. |
| * Angles are interpreted such that 0 degrees |
| * is at the 3 o'clock position. |
| * A positive value indicates a counter-clockwise rotation |
| * while a negative value indicates a clockwise rotation. |
| * <p> |
| * The center of the arc is the center of the rectangle whose origin |
| * is (<i>x</i>, <i>y</i>) and whose size is specified by the |
| * <code>width</code> and <code>height</code> arguments. |
| * <p> |
| * The resulting arc covers an area |
| * <code>width + 1</code> pixels wide |
| * by <code>height + 1</code> pixels tall. |
| * <p> |
| * The angles are specified relative to the non-square extents of |
| * the bounding rectangle such that 45 degrees always falls on the |
| * line from the center of the ellipse to the upper right corner of |
| * the bounding rectangle. As a result, if the bounding rectangle is |
| * noticeably longer in one axis than the other, the angles to the |
| * start and end of the arc segment will be skewed farther along the |
| * longer axis of the bounds. |
| * @param x the <i>x</i> coordinate of the |
| * upper-left corner of the arc to be drawn. |
| * @param y the <i>y</i> coordinate of the |
| * upper-left corner of the arc to be drawn. |
| * @param width the width of the arc to be drawn. |
| * @param height the height of the arc to be drawn. |
| * @param startAngle the beginning angle. |
| * @param arcAngle the angular extent of the arc, |
| * relative to the start angle. |
| * @see java.awt.Graphics#fillArc |
| */ |
| public abstract void drawArc(int x, int y, int width, int height, |
| int startAngle, int arcAngle); |
| |
| /** |
| * Fills a circular or elliptical arc covering the specified rectangle. |
| * <p> |
| * The resulting arc begins at <code>startAngle</code> and extends |
| * for <code>arcAngle</code> degrees. |
| * Angles are interpreted such that 0 degrees |
| * is at the 3 o'clock position. |
| * A positive value indicates a counter-clockwise rotation |
| * while a negative value indicates a clockwise rotation. |
| * <p> |
| * The center of the arc is the center of the rectangle whose origin |
| * is (<i>x</i>, <i>y</i>) and whose size is specified by the |
| * <code>width</code> and <code>height</code> arguments. |
| * <p> |
| * The resulting arc covers an area |
| * <code>width + 1</code> pixels wide |
| * by <code>height + 1</code> pixels tall. |
| * <p> |
| * The angles are specified relative to the non-square extents of |
| * the bounding rectangle such that 45 degrees always falls on the |
| * line from the center of the ellipse to the upper right corner of |
| * the bounding rectangle. As a result, if the bounding rectangle is |
| * noticeably longer in one axis than the other, the angles to the |
| * start and end of the arc segment will be skewed farther along the |
| * longer axis of the bounds. |
| * @param x the <i>x</i> coordinate of the |
| * upper-left corner of the arc to be filled. |
| * @param y the <i>y</i> coordinate of the |
| * upper-left corner of the arc to be filled. |
| * @param width the width of the arc to be filled. |
| * @param height the height of the arc to be filled. |
| * @param startAngle the beginning angle. |
| * @param arcAngle the angular extent of the arc, |
| * relative to the start angle. |
| * @see java.awt.Graphics#drawArc |
| */ |
| public abstract void fillArc(int x, int y, int width, int height, |
| int startAngle, int arcAngle); |
| |
| /** |
| * Draws a sequence of connected lines defined by |
| * arrays of <i>x</i> and <i>y</i> coordinates. |
| * Each pair of (<i>x</i>, <i>y</i>) coordinates defines a point. |
| * The figure is not closed if the first point |
| * differs from the last point. |
| * @param xPoints an array of <i>x</i> points |
| * @param yPoints an array of <i>y</i> points |
| * @param nPoints the total number of points |
| * @see java.awt.Graphics#drawPolygon(int[], int[], int) |
| * @since JDK1.1 |
| */ |
| public abstract void drawPolyline(int xPoints[], int yPoints[], |
| int nPoints); |
| |
| /** |
| * Draws a closed polygon defined by |
| * arrays of <i>x</i> and <i>y</i> coordinates. |
| * Each pair of (<i>x</i>, <i>y</i>) coordinates defines a point. |
| * <p> |
| * This method draws the polygon defined by <code>nPoint</code> line |
| * segments, where the first <code>nPoint - 1</code> |
| * line segments are line segments from |
| * <code>(xPoints[i - 1], yPoints[i - 1])</code> |
| * to <code>(xPoints[i], yPoints[i])</code>, for |
| * 1 ≤ <i>i</i> ≤ <code>nPoints</code>. |
| * The figure is automatically closed by drawing a line connecting |
| * the final point to the first point, if those points are different. |
| * @param xPoints a an array of <code>x</code> coordinates. |
| * @param yPoints a an array of <code>y</code> coordinates. |
| * @param nPoints a the total number of points. |
| * @see java.awt.Graphics#fillPolygon |
| * @see java.awt.Graphics#drawPolyline |
| */ |
| public abstract void drawPolygon(int xPoints[], int yPoints[], |
| int nPoints); |
| |
| /** |
| * Draws the outline of a polygon defined by the specified |
| * <code>Polygon</code> object. |
| * @param p the polygon to draw. |
| * @see java.awt.Graphics#fillPolygon |
| * @see java.awt.Graphics#drawPolyline |
| */ |
| public void drawPolygon(Polygon p) { |
| drawPolygon(p.xpoints, p.ypoints, p.npoints); |
| } |
| |
| /** |
| * Fills a closed polygon defined by |
| * arrays of <i>x</i> and <i>y</i> coordinates. |
| * <p> |
| * This method draws the polygon defined by <code>nPoint</code> line |
| * segments, where the first <code>nPoint - 1</code> |
| * line segments are line segments from |
| * <code>(xPoints[i - 1], yPoints[i - 1])</code> |
| * to <code>(xPoints[i], yPoints[i])</code>, for |
| * 1 ≤ <i>i</i> ≤ <code>nPoints</code>. |
| * The figure is automatically closed by drawing a line connecting |
| * the final point to the first point, if those points are different. |
| * <p> |
| * The area inside the polygon is defined using an |
| * even-odd fill rule, also known as the alternating rule. |
| * @param xPoints a an array of <code>x</code> coordinates. |
| * @param yPoints a an array of <code>y</code> coordinates. |
| * @param nPoints a the total number of points. |
| * @see java.awt.Graphics#drawPolygon(int[], int[], int) |
| */ |
| public abstract void fillPolygon(int xPoints[], int yPoints[], |
| int nPoints); |
| |
| /** |
| * Fills the polygon defined by the specified Polygon object with |
| * the graphics context's current color. |
| * <p> |
| * The area inside the polygon is defined using an |
| * even-odd fill rule, also known as the alternating rule. |
| * @param p the polygon to fill. |
| * @see java.awt.Graphics#drawPolygon(int[], int[], int) |
| */ |
| public void fillPolygon(Polygon p) { |
| fillPolygon(p.xpoints, p.ypoints, p.npoints); |
| } |
| |
| /** |
| * Draws the text given by the specified string, using this |
| * graphics context's current font and color. The baseline of the |
| * leftmost character is at position (<i>x</i>, <i>y</i>) in this |
| * graphics context's coordinate system. |
| * @param str the string to be drawn. |
| * @param x the <i>x</i> coordinate. |
| * @param y the <i>y</i> coordinate. |
| * @throws NullPointerException if <code>str</code> is <code>null</code>. |
| * @see java.awt.Graphics#drawBytes |
| * @see java.awt.Graphics#drawChars |
| */ |
| public abstract void drawString(String str, int x, int y); |
| |
| /** |
| * Renders the text of the specified iterator applying its attributes |
| * in accordance with the specification of the |
| * {@link java.awt.font.TextAttribute TextAttribute} class. |
| * <p> |
| * The baseline of the leftmost character is at position |
| * (<i>x</i>, <i>y</i>) in this graphics context's coordinate system. |
| * @param iterator the iterator whose text is to be drawn |
| * @param x the <i>x</i> coordinate. |
| * @param y the <i>y</i> coordinate. |
| * @throws NullPointerException if <code>iterator</code> is |
| * <code>null</code>. |
| * @see java.awt.Graphics#drawBytes |
| * @see java.awt.Graphics#drawChars |
| */ |
| public abstract void drawString(AttributedCharacterIterator iterator, |
| int x, int y); |
| |
| /** |
| * Draws the text given by the specified character array, using this |
| * graphics context's current font and color. The baseline of the |
| * first character is at position (<i>x</i>, <i>y</i>) in this |
| * graphics context's coordinate system. |
| * @param data the array of characters to be drawn |
| * @param offset the start offset in the data |
| * @param length the number of characters to be drawn |
| * @param x the <i>x</i> coordinate of the baseline of the text |
| * @param y the <i>y</i> coordinate of the baseline of the text |
| * @throws NullPointerException if <code>data</code> is <code>null</code>. |
| * @throws IndexOutOfBoundsException if <code>offset</code> or |
| * <code>length</code>is less than zero, or |
| * <code>offset+length</code> is greater than the length of the |
| * <code>data</code> array. |
| * @see java.awt.Graphics#drawBytes |
| * @see java.awt.Graphics#drawString |
| */ |
| public void drawChars(char data[], int offset, int length, int x, int y) { |
| drawString(new String(data, offset, length), x, y); |
| } |
| |
| /** |
| * Draws the text given by the specified byte array, using this |
| * graphics context's current font and color. The baseline of the |
| * first character is at position (<i>x</i>, <i>y</i>) in this |
| * graphics context's coordinate system. |
| * <p> |
| * Use of this method is not recommended as each byte is interpreted |
| * as a Unicode code point in the range 0 to 255, and so can only be |
| * used to draw Latin characters in that range. |
| * @param data the data to be drawn |
| * @param offset the start offset in the data |
| * @param length the number of bytes that are drawn |
| * @param x the <i>x</i> coordinate of the baseline of the text |
| * @param y the <i>y</i> coordinate of the baseline of the text |
| * @throws NullPointerException if <code>data</code> is <code>null</code>. |
| * @throws IndexOutOfBoundsException if <code>offset</code> or |
| * <code>length</code>is less than zero, or <code>offset+length</code> |
| * is greater than the length of the <code>data</code> array. |
| * @see java.awt.Graphics#drawChars |
| * @see java.awt.Graphics#drawString |
| */ |
| public void drawBytes(byte data[], int offset, int length, int x, int y) { |
| drawString(new String(data, 0, offset, length), x, y); |
| } |
| |
| /** |
| * Draws as much of the specified image as is currently available. |
| * The image is drawn with its top-left corner at |
| * (<i>x</i>, <i>y</i>) in this graphics context's coordinate |
| * space. Transparent pixels in the image do not affect whatever |
| * pixels are already there. |
| * <p> |
| * This method returns immediately in all cases, even if the |
| * complete image has not yet been loaded, and it has not been dithered |
| * and converted for the current output device. |
| * <p> |
| * If the image has completely loaded and its pixels are |
| * no longer being changed, then |
| * <code>drawImage</code> returns <code>true</code>. |
| * Otherwise, <code>drawImage</code> returns <code>false</code> |
| * and as more of |
| * the image becomes available |
| * or it is time to draw another frame of animation, |
| * the process that loads the image notifies |
| * the specified image observer. |
| * @param img the specified image to be drawn. This method does |
| * nothing if <code>img</code> is null. |
| * @param x the <i>x</i> coordinate. |
| * @param y the <i>y</i> coordinate. |
| * @param observer object to be notified as more of |
| * the image is converted. |
| * @return <code>false</code> if the image pixels are still changing; |
| * <code>true</code> otherwise. |
| * @see java.awt.Image |
| * @see java.awt.image.ImageObserver |
| * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int) |
| */ |
| public abstract boolean drawImage(Image img, int x, int y, |
| ImageObserver observer); |
| |
| /** |
| * Draws as much of the specified image as has already been scaled |
| * to fit inside the specified rectangle. |
| * <p> |
| * The image is drawn inside the specified rectangle of this |
| * graphics context's coordinate space, and is scaled if |
| * necessary. Transparent pixels do not affect whatever pixels |
| * are already there. |
| * <p> |
| * This method returns immediately in all cases, even if the |
| * entire image has not yet been scaled, dithered, and converted |
| * for the current output device. |
| * If the current output representation is not yet complete, then |
| * <code>drawImage</code> returns <code>false</code>. As more of |
| * the image becomes available, the process that loads the image notifies |
| * the image observer by calling its <code>imageUpdate</code> method. |
| * <p> |
| * A scaled version of an image will not necessarily be |
| * available immediately just because an unscaled version of the |
| * image has been constructed for this output device. Each size of |
| * the image may be cached separately and generated from the original |
| * data in a separate image production sequence. |
| * @param img the specified image to be drawn. This method does |
| * nothing if <code>img</code> is null. |
| * @param x the <i>x</i> coordinate. |
| * @param y the <i>y</i> coordinate. |
| * @param width the width of the rectangle. |
| * @param height the height of the rectangle. |
| * @param observer object to be notified as more of |
| * the image is converted. |
| * @return <code>false</code> if the image pixels are still changing; |
| * <code>true</code> otherwise. |
| * @see java.awt.Image |
| * @see java.awt.image.ImageObserver |
| * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int) |
| */ |
| public abstract boolean drawImage(Image img, int x, int y, |
| int width, int height, |
| ImageObserver observer); |
| |
| /** |
| * Draws as much of the specified image as is currently available. |
| * The image is drawn with its top-left corner at |
| * (<i>x</i>, <i>y</i>) in this graphics context's coordinate |
| * space. Transparent pixels are drawn in the specified |
| * background color. |
| * <p> |
| * This operation is equivalent to filling a rectangle of the |
| * width and height of the specified image with the given color and then |
| * drawing the image on top of it, but possibly more efficient. |
| * <p> |
| * This method returns immediately in all cases, even if the |
| * complete image has not yet been loaded, and it has not been dithered |
| * and converted for the current output device. |
| * <p> |
| * If the image has completely loaded and its pixels are |
| * no longer being changed, then |
| * <code>drawImage</code> returns <code>true</code>. |
| * Otherwise, <code>drawImage</code> returns <code>false</code> |
| * and as more of |
| * the image becomes available |
| * or it is time to draw another frame of animation, |
| * the process that loads the image notifies |
| * the specified image observer. |
| * @param img the specified image to be drawn. This method does |
| * nothing if <code>img</code> is null. |
| * @param x the <i>x</i> coordinate. |
| * @param y the <i>y</i> coordinate. |
| * @param bgcolor the background color to paint under the |
| * non-opaque portions of the image. |
| * @param observer object to be notified as more of |
| * the image is converted. |
| * @return <code>false</code> if the image pixels are still changing; |
| * <code>true</code> otherwise. |
| * @see java.awt.Image |
| * @see java.awt.image.ImageObserver |
| * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int) |
| */ |
| public abstract boolean drawImage(Image img, int x, int y, |
| Color bgcolor, |
| ImageObserver observer); |
| |
| /** |
| * Draws as much of the specified image as has already been scaled |
| * to fit inside the specified rectangle. |
| * <p> |
| * The image is drawn inside the specified rectangle of this |
| * graphics context's coordinate space, and is scaled if |
| * necessary. Transparent pixels are drawn in the specified |
| * background color. |
| * This operation is equivalent to filling a rectangle of the |
| * width and height of the specified image with the given color and then |
| * drawing the image on top of it, but possibly more efficient. |
| * <p> |
| * This method returns immediately in all cases, even if the |
| * entire image has not yet been scaled, dithered, and converted |
| * for the current output device. |
| * If the current output representation is not yet complete then |
| * <code>drawImage</code> returns <code>false</code>. As more of |
| * the image becomes available, the process that loads the image notifies |
| * the specified image observer. |
| * <p> |
| * A scaled version of an image will not necessarily be |
| * available immediately just because an unscaled version of the |
| * image has been constructed for this output device. Each size of |
| * the image may be cached separately and generated from the original |
| * data in a separate image production sequence. |
| * @param img the specified image to be drawn. This method does |
| * nothing if <code>img</code> is null. |
| * @param x the <i>x</i> coordinate. |
| * @param y the <i>y</i> coordinate. |
| * @param width the width of the rectangle. |
| * @param height the height of the rectangle. |
| * @param bgcolor the background color to paint under the |
| * non-opaque portions of the image. |
| * @param observer object to be notified as more of |
| * the image is converted. |
| * @return <code>false</code> if the image pixels are still changing; |
| * <code>true</code> otherwise. |
| * @see java.awt.Image |
| * @see java.awt.image.ImageObserver |
| * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int) |
| */ |
| public abstract boolean drawImage(Image img, int x, int y, |
| int width, int height, |
| Color bgcolor, |
| ImageObserver observer); |
| |
| /** |
| * Draws as much of the specified area of the specified image as is |
| * currently available, scaling it on the fly to fit inside the |
| * specified area of the destination drawable surface. Transparent pixels |
| * do not affect whatever pixels are already there. |
| * <p> |
| * This method returns immediately in all cases, even if the |
| * image area to be drawn has not yet been scaled, dithered, and converted |
| * for the current output device. |
| * If the current output representation is not yet complete then |
| * <code>drawImage</code> returns <code>false</code>. As more of |
| * the image becomes available, the process that loads the image notifies |
| * the specified image observer. |
| * <p> |
| * This method always uses the unscaled version of the image |
| * to render the scaled rectangle and performs the required |
| * scaling on the fly. It does not use a cached, scaled version |
| * of the image for this operation. Scaling of the image from source |
| * to destination is performed such that the first coordinate |
| * of the source rectangle is mapped to the first coordinate of |
| * the destination rectangle, and the second source coordinate is |
| * mapped to the second destination coordinate. The subimage is |
| * scaled and flipped as needed to preserve those mappings. |
| * @param img the specified image to be drawn. This method does |
| * nothing if <code>img</code> is null. |
| * @param dx1 the <i>x</i> coordinate of the first corner of the |
| * destination rectangle. |
| * @param dy1 the <i>y</i> coordinate of the first corner of the |
| * destination rectangle. |
| * @param dx2 the <i>x</i> coordinate of the second corner of the |
| * destination rectangle. |
| * @param dy2 the <i>y</i> coordinate of the second corner of the |
| * destination rectangle. |
| * @param sx1 the <i>x</i> coordinate of the first corner of the |
| * source rectangle. |
| * @param sy1 the <i>y</i> coordinate of the first corner of the |
| * source rectangle. |
| * @param sx2 the <i>x</i> coordinate of the second corner of the |
| * source rectangle. |
| * @param sy2 the <i>y</i> coordinate of the second corner of the |
| * source rectangle. |
| * @param observer object to be notified as more of the image is |
| * scaled and converted. |
| * @return <code>false</code> if the image pixels are still changing; |
| * <code>true</code> otherwise. |
| * @see java.awt.Image |
| * @see java.awt.image.ImageObserver |
| * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int) |
| * @since JDK1.1 |
| */ |
| public abstract boolean drawImage(Image img, |
| int dx1, int dy1, int dx2, int dy2, |
| int sx1, int sy1, int sx2, int sy2, |
| ImageObserver observer); |
| |
| /** |
| * Draws as much of the specified area of the specified image as is |
| * currently available, scaling it on the fly to fit inside the |
| * specified area of the destination drawable surface. |
| * <p> |
| * Transparent pixels are drawn in the specified background color. |
| * This operation is equivalent to filling a rectangle of the |
| * width and height of the specified image with the given color and then |
| * drawing the image on top of it, but possibly more efficient. |
| * <p> |
| * This method returns immediately in all cases, even if the |
| * image area to be drawn has not yet been scaled, dithered, and converted |
| * for the current output device. |
| * If the current output representation is not yet complete then |
| * <code>drawImage</code> returns <code>false</code>. As more of |
| * the image becomes available, the process that loads the image notifies |
| * the specified image observer. |
| * <p> |
| * This method always uses the unscaled version of the image |
| * to render the scaled rectangle and performs the required |
| * scaling on the fly. It does not use a cached, scaled version |
| * of the image for this operation. Scaling of the image from source |
| * to destination is performed such that the first coordinate |
| * of the source rectangle is mapped to the first coordinate of |
| * the destination rectangle, and the second source coordinate is |
| * mapped to the second destination coordinate. The subimage is |
| * scaled and flipped as needed to preserve those mappings. |
| * @param img the specified image to be drawn. This method does |
| * nothing if <code>img</code> is null. |
| * @param dx1 the <i>x</i> coordinate of the first corner of the |
| * destination rectangle. |
| * @param dy1 the <i>y</i> coordinate of the first corner of the |
| * destination rectangle. |
| * @param dx2 the <i>x</i> coordinate of the second corner of the |
| * destination rectangle. |
| * @param dy2 the <i>y</i> coordinate of the second corner of the |
| * destination rectangle. |
| * @param sx1 the <i>x</i> coordinate of the first corner of the |
| * source rectangle. |
| * @param sy1 the <i>y</i> coordinate of the first corner of the |
| * source rectangle. |
| * @param sx2 the <i>x</i> coordinate of the second corner of the |
| * source rectangle. |
| * @param sy2 the <i>y</i> coordinate of the second corner of the |
| * source rectangle. |
| * @param bgcolor the background color to paint under the |
| * non-opaque portions of the image. |
| * @param observer object to be notified as more of the image is |
| * scaled and converted. |
| * @return <code>false</code> if the image pixels are still changing; |
| * <code>true</code> otherwise. |
| * @see java.awt.Image |
| * @see java.awt.image.ImageObserver |
| * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int) |
| * @since JDK1.1 |
| */ |
| public abstract boolean drawImage(Image img, |
| int dx1, int dy1, int dx2, int dy2, |
| int sx1, int sy1, int sx2, int sy2, |
| Color bgcolor, |
| ImageObserver observer); |
| |
| /** |
| * Disposes of this graphics context and releases |
| * any system resources that it is using. |
| * A <code>Graphics</code> object cannot be used after |
| * <code>dispose</code>has been called. |
| * <p> |
| * When a Java program runs, a large number of <code>Graphics</code> |
| * objects can be created within a short time frame. |
| * Although the finalization process of the garbage collector |
| * also disposes of the same system resources, it is preferable |
| * to manually free the associated resources by calling this |
| * method rather than to rely on a finalization process which |
| * may not run to completion for a long period of time. |
| * <p> |
| * Graphics objects which are provided as arguments to the |
| * <code>paint</code> and <code>update</code> methods |
| * of components are automatically released by the system when |
| * those methods return. For efficiency, programmers should |
| * call <code>dispose</code> when finished using |
| * a <code>Graphics</code> object only if it was created |
| * directly from a component or another <code>Graphics</code> object. |
| * @see java.awt.Graphics#finalize |
| * @see java.awt.Component#paint |
| * @see java.awt.Component#update |
| * @see java.awt.Component#getGraphics |
| * @see java.awt.Graphics#create |
| */ |
| public abstract void dispose(); |
| |
| /** |
| * Disposes of this graphics context once it is no longer referenced. |
| * @see #dispose |
| */ |
| public void finalize() { |
| dispose(); |
| } |
| |
| /** |
| * Returns a <code>String</code> object representing this |
| * <code>Graphics</code> object's value. |
| * @return a string representation of this graphics context. |
| */ |
| public String toString() { |
| return getClass().getName() + "[font=" + getFont() + ",color=" + getColor() + "]"; |
| } |
| |
| /** |
| * Returns the bounding rectangle of the current clipping area. |
| * @return the bounding rectangle of the current clipping area |
| * or <code>null</code> if no clip is set. |
| * @deprecated As of JDK version 1.1, |
| * replaced by <code>getClipBounds()</code>. |
| */ |
| @Deprecated |
| public Rectangle getClipRect() { |
| return getClipBounds(); |
| } |
| |
| /** |
| * Returns true if the specified rectangular area might intersect |
| * the current clipping area. |
| * The coordinates of the specified rectangular area are in the |
| * user coordinate space and are relative to the coordinate |
| * system origin of this graphics context. |
| * This method may use an algorithm that calculates a result quickly |
| * but which sometimes might return true even if the specified |
| * rectangular area does not intersect the clipping area. |
| * The specific algorithm employed may thus trade off accuracy for |
| * speed, but it will never return false unless it can guarantee |
| * that the specified rectangular area does not intersect the |
| * current clipping area. |
| * The clipping area used by this method can represent the |
| * intersection of the user clip as specified through the clip |
| * methods of this graphics context as well as the clipping |
| * associated with the device or image bounds and window visibility. |
| * |
| * @param x the x coordinate of the rectangle to test against the clip |
| * @param y the y coordinate of the rectangle to test against the clip |
| * @param width the width of the rectangle to test against the clip |
| * @param height the height of the rectangle to test against the clip |
| * @return <code>true</code> if the specified rectangle intersects |
| * the bounds of the current clip; <code>false</code> |
| * otherwise. |
| */ |
| public boolean hitClip(int x, int y, int width, int height) { |
| // Note, this implementation is not very efficient. |
| // Subclasses should override this method and calculate |
| // the results more directly. |
| Rectangle clipRect = getClipBounds(); |
| if (clipRect == null) { |
| return true; |
| } |
| return clipRect.intersects(x, y, width, height); |
| } |
| |
| /** |
| * Returns the bounding rectangle of the current clipping area. |
| * The coordinates in the rectangle are relative to the coordinate |
| * system origin of this graphics context. This method differs |
| * from {@link #getClipBounds() getClipBounds} in that an existing |
| * rectangle is used instead of allocating a new one. |
| * This method refers to the user clip, which is independent of the |
| * clipping associated with device bounds and window visibility. |
| * If no clip has previously been set, or if the clip has been |
| * cleared using <code>setClip(null)</code>, this method returns the |
| * specified <code>Rectangle</code>. |
| * @param r the rectangle where the current clipping area is |
| * copied to. Any current values in this rectangle are |
| * overwritten. |
| * @return the bounding rectangle of the current clipping area. |
| */ |
| public Rectangle getClipBounds(Rectangle r) { |
| // Note, this implementation is not very efficient. |
| // Subclasses should override this method and avoid |
| // the allocation overhead of getClipBounds(). |
| Rectangle clipRect = getClipBounds(); |
| if (clipRect != null) { |
| r.x = clipRect.x; |
| r.y = clipRect.y; |
| r.width = clipRect.width; |
| r.height = clipRect.height; |
| } else if (r == null) { |
| throw new NullPointerException("null rectangle parameter"); |
| } |
| return r; |
| } |
| } |
