/*
* @(#)Graphics.java 1.43 98/08/19
*
* Copyright 1995-1998 by Sun Microsystems, Inc.,
* 901 San Antonio Road, Palo Alto, California, 94303, U.S.A.
* All rights reserved.
*
* This software is the confidential and proprietary information
* of Sun Microsystems, Inc. ("Confidential Information"). You
* shall not disclose such Confidential Information and shall use
* it only in accordance with the terms of the license agreement
* you entered into with Sun.
*/
package java.awt;
import java.io.*;
import java.lang.*;
import java.util.*;
import java.awt.image.ImageObserver;
/**
* The Graphics
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.
*
* A Graphics
object encapsulates state information needed
* for the basic rendering operations that Java supports. This
* state information includes the following properties:
*
*
Component
object on which to draw.
* setXORMode
).
* * Coordinates are infinitely thin and lie between the pixels of the * output device. * Operations which 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 which fill a figure operate by filling the interior * of that infinitely thin path. * Operations which render horizontal text render the ascending * portion of character glyphs entirely above the baseline coordinate. *
* The graphics pen hangs down and to the right from the path it traverses. * This has the following implications: *
* All coordinates which appear as arguments to the methods of this
* Graphics
object are considered relative to the
* translation origin of this Graphics
object prior to
* the invocation of the method.
* All rendering operations modify only pixels which lie within the
* area bounded by both the current clip of the graphics context
* and the extents of the component used to create the
* Graphics
object.
* All drawing or writing is done in the current color,
* using the current paint mode, and in the current font.
*
* @version 1.43, 08/19/98
* @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 Graphics
object.
* This constructor is the default contructor for a graphics
* context.
*
* Since Graphics
is an abstract class, applications
* cannot call this constructor directly. Graphics contexts are
* obtained from other graphics contexts or are created by calling
* getGraphics
on a component.
* @see java.awt.Graphics#create()
* @see java.awt.Component#getGraphics
* @since JDK1.0
*/
protected Graphics() {
}
/**
* Creates a new Graphics
object that is
* a copy of this Graphics
object.
* @return a new graphics context that is a copy of
* this graphics context.
* @since JDK1.0
*/
public abstract Graphics create();
/**
* Creates a new Graphics
object based on this
* Graphics
object, but with a new translation and clip area.
* The new Graphics
object has its origin
* translated to the specified point (x, y).
* 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
* Graphics
object. The new graphics context is
* identical to the original, except in two respects:
*
*
0
, 0
) in the
* new graphics context is the same as (x, y) in
* the original graphics context.
* 0
, 0
), and its size
* is specified by the width
and height
arguments.
* * @param x the x coordinate. * @param y the y 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 * @since JDK1.0 */ public Graphics create(int x, int y, int width, int height) { Graphics g = create(); g.translate(x, y); g.clipRect(0, 0, width, height); return g; } /** * Translates the origin of the graphics context to the point * (x, y) in the current coordinate system. * Modifies this graphics context so that its new origin corresponds * to the point (x, y) 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 x coordinate. * @param y the y coordinate. * @since JDK1.0 */ 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 * @since JDK1.0 */ 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 * @since JDK1.0 */ 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. * @since JDK1.0 */ 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. *
* When drawing operations are performed, pixels which are the * current color are changed to the specified color, and vice versa. *
* 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
* @since JDK1.0
*/
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
* @since JDK1.0
*/
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.
* @param font the font.
* @see java.awt.Graphics#getFont
* @see java.awt.Graphics#drawChars(java.lang.String, int, int)
* @see java.awt.Graphics#drawString(byte[], int, int, int, int)
* @see java.awt.Graphics#drawBytes(char[], int, int, int, int)
* @since JDK1.0
*/
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)
* @since JDK1.0
*/
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()
* @since JDK1.0
*/
public abstract FontMetrics getFontMetrics(Font f);
/**
* 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.
* @return the bounding rectangle of the current clipping area.
* @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.
* 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.
* Rendering operations have no effect outside of the clipping area.
* @param x the x coordinate of the new clip rectangle.
* @param y the y 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)
* @since JDK1.1
*/
public abstract void setClip(int x, int y, int width, int height);
/**
* Gets the current clipping area.
* @return a Shape
object representing the
* current clipping area.
* @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 which implement the Shape
* interface can be used to set the clip. The only
* Shape
objects which are guaranteed to be
* supported are Shape
objects which are
* obtained via the getClip
method and via
* Rectangle
objects.
* @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
* dx
and dy
. From the point specified
* by x
and y
, 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
* dx
or dy
.
* If a portion of the source rectangle lies outside the bounds
* of the component, or is obscured by another window or component,
* copyArea
will be unable to copy the associated
* pixels. The area that is omitted can be refreshed by calling
* the component's paint
method.
* @param x the x coordinate of the source rectangle.
* @param y the y 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.
* @since JDK1.0
*/
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
* (x1, y1)
and (x2, y2)
* in this graphics context's coordinate system.
* @param x1 the first point's x coordinate.
* @param y1 the first point's y coordinate.
* @param x2 the second point's x coordinate.
* @param y2 the second point's y coordinate.
* @since JDK1.0
*/
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
* x
and x + width - 1
.
* The top and bottom edges are at
* y
and y + height - 1
.
* The resulting rectangle covers an area
* width
pixels wide by
* height
pixels tall.
* The rectangle is filled using the graphics context's current color.
* @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.
* @see java.awt.Graphics#fillRect
* @see java.awt.Graphics#clearRect
* @since JDK1.0
*/
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
* x
and x + width
.
* The top and bottom edges are at
* y
and y + height
.
* The rectangle is drawn using the graphics context's current color.
* @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.
* @see java.awt.Graphics#fillRect
* @see java.awt.Graphics#clearRect
* @since JDK1.0
*/
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.
*
* Beginning with Java 1.1, the background color
* of offscreen images may be system dependent. Applications should
* use setColor
followed by fillRect
to
* ensure that an offscreen image is cleared to a specific color.
* @param x the x coordinate of the rectangle to clear.
* @param y the y 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)
* @since JDK1.0
*/
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 x
and x + width
,
* respectively. The top and bottom edges of the rectangle are at
* y
and y + height
.
* @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 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
* @since JDK1.0
*/
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 x
and x + width - 1
,
* respectively. The top and bottom edges of the rectangle are at
* y
and y + height - 1
.
* @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 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
* @since JDK1.0
*/
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.
*
* 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.
* @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
* @since JDK1.0
*/
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 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
* @since JDK1.0
*/
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 x
, y
,
* width
, and height
arguments.
*
* The oval covers an area that is
*
* The resulting arc begins at
* The center of the arc is the center of the rectangle whose origin
* is (x, y) and whose size is specified by the
*
* The resulting arc covers an area
*
* The resulting arc begins at
* The center of the arc is the center of the rectangle whose origin
* is (x, y) and whose size is specified by the
*
* The resulting arc covers an area
*
* This method draws the polygon defined by
* This method draws the polygon defined by
* 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
* 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)
* @since JDK1.0
*/
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
* first character is at position (x, y) in this
* graphics context's coordinate system.
* @param str the string to be drawn.
* @param x the x coordinate.
* @param y the y coordinate.
* @see java.awt.Graphics#drawBytes
* @see java.awt.Graphics#drawChars
* @since JDK1.0
*/
public abstract void drawString(String str, 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 (x, y) 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 x coordinate of the baseline of the text
* @param y the y coordinate of the baseline of the text
* @see java.awt.Graphics#drawBytes
* @see java.awt.Graphics#drawString
* @since JDK1.0
*/
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 (x, y) in this
* graphics context's coordinate system.
* @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 x coordinate of the baseline of the text
* @param y the y coordinate of the baseline of the text
* @see java.awt.Graphics#drawChars
* @see java.awt.Graphics#drawString
* @since JDK1.0
*/
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
* (x, y) in this graphics context's coordinate
* space. Transparent pixels in the image do not affect whatever
* pixels are already there.
*
* 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.
*
* If the image has not yet been completely loaded, then
*
* 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.
*
* 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
*
* 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.
* @param x the x coordinate.
* @param y the y 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.
* @see java.awt.Image
* @see java.awt.image.ImageObserver
* @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
* @since JDK1.0
*/
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
* (x, y) in this graphics context's coordinate
* space. 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.
*
* 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.
*
* If the image has not yet been completely loaded, then
*
* 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.
*
* 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
*
* 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.
* @param x the x coordinate.
* @param y the y 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.
* @see java.awt.Image
* @see java.awt.image.ImageObserver
* @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
* @since JDK1.0
*/
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.
*
* 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
*
* 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
* @param dx1 the x coordinate of the first corner of the
* destination rectangle.
* @param dy1 the y coordinate of the first corner of the
* destination rectangle.
* @param dx2 the x coordinate of the second corner of the
* destination rectangle.
* @param dy2 the y coordinate of the second corner of the
* destination rectangle.
* @param sx1 the x coordinate of the first corner of the
* source rectangle.
* @param sy1 the y coordinate of the first corner of the
* source rectangle.
* @param sx2 the x coordinate of the second corner of the
* source rectangle.
* @param sy2 the y coordinate of the second corner of the
* source rectangle.
* @param observer object to be notified as more of the image is
* scaled and converted.
* @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.
*
* 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.
*
* 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
*
* 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
* @param dx1 the x coordinate of the first corner of the
* destination rectangle.
* @param dy1 the y coordinate of the first corner of the
* destination rectangle.
* @param dx2 the x coordinate of the second corner of the
* destination rectangle.
* @param dy2 the y coordinate of the second corner of the
* destination rectangle.
* @param sx1 the x coordinate of the first corner of the
* source rectangle.
* @param sy1 the y coordinate of the first corner of the
* source rectangle.
* @param sx2 the x coordinate of the second corner of the
* source rectangle.
* @param sy2 the y 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.
* @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
* When a Java program runs, a large number of
* Graphics objects which are provided as arguments to the
* width + 1
pixels wide
* and height + 1
pixels tall.
* @param x the x coordinate of the upper left
* corner of the oval to be drawn.
* @param y the y 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
* @since JDK1.0
*/
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 x coordinate of the upper left corner
* of the oval to be filled.
* @param y the y 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
* @since JDK1.0
*/
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.
*
startAngle
and extends
* for arcAngle
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.
* width
and height
arguments.
* width + 1
pixels wide
* by height + 1
pixels tall.
* @param x the x coordinate of the
* upper-left corner of the arc to be drawn.
* @param y the y 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
* @since JDK1.0
*/
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.
* startAngle
and extends
* for arcAngle
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.
* width
and height
arguments.
* width + 1
pixels wide
* by height + 1
pixels tall.
* @param x the x coordinate of the
* upper-left corner of the arc to be filled.
* @param y the y 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
* @since JDK1.0
*/
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 x and y coordinates.
* Each pair of (x, y) coordinates defines a point.
* The figure is not closed if the first point
* differs from the last point.
* @param xPoints an array of x points
* @param yPoints an array of y 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 x and y coordinates.
* Each pair of (x, y) coordinates defines a point.
* nPoint
line
* segments, where the first nPoint - 1
* line segments are line segments from
* (xPoints[i - 1], yPoints[i - 1])
* to (xPoints[i], yPoints[i])
, for
* 1 ≤ i ≤ nPoints
.
* 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 x
coordinates.
* @param yPoints a an array of y
coordinates.
* @param nPoints a the total number of points.
* @see java.awt.Graphics#fillPolygon
* @see java.awt.Graphics#drawPolyline
* @since JDK1.0
*/
public abstract void drawPolygon(int xPoints[], int yPoints[],
int nPoints);
/**
* Draws the outline of a polygon defined by the specified
* Polygon
object.
* @param p the polygon to draw.
* @see java.awt.Graphics#fillPolygon
* @see java.awt.Graphics#drawPolyline
* @since JDK1.0
*/
public void drawPolygon(Polygon p) {
drawPolygon(p.xpoints, p.ypoints, p.npoints);
}
/**
* Fills a closed polygon defined by
* arrays of x and y coordinates.
* nPoint
line
* segments, where the first nPoint - 1
* line segments are line segments from
* (xPoints[i - 1], yPoints[i - 1])
* to (xPoints[i], yPoints[i])
, for
* 1 ≤ i ≤ nPoints
.
* The figure is automatically closed by drawing a line connecting
* the final point to the first point, if those points are different.
* x
coordinates.
* @param yPoints a an array of y
coordinates.
* @param nPoints a the total number of points.
* @see java.awt.Graphics#drawPolygon(int[], int[], int)
* @since JDK1.0
*/
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.
* drawImage
returns false
. As more of
* the image becomes available, the process that draws the image notifies
* the specified image observer.
* @param img the specified image to be drawn.
* @param x the x coordinate.
* @param y the y coordinate.
* @param observer object to be notified as more of
* the image is converted.
* @see java.awt.Image
* @see java.awt.image.ImageObserver
* @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
* @since JDK1.0
*/
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.
* drawImage
returns false
. As more of
* the image becomes available, the process that draws the image notifies
* the image observer by calling its imageUpdate
method.
* drawImage
returns false
. As more of
* the image becomes available, the process that draws the image notifies
* the specified image observer.
* @param img the specified image to be drawn.
* @param x the x coordinate.
* @param y the y 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.
* @see java.awt.Image
* @see java.awt.image.ImageObserver
* @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
* @since JDK1.0
*/
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.
* drawImage
returns false
. As more of
* the image becomes available, the process that draws the image notifies
* the specified image observer.
* drawImage
returns false
. As more of
* the image becomes available, the process that draws the image notifies
* the specified image observer.
* drawImage
returns false
. As more of
* the image becomes available, the process that draws the image notifies
* the specified image observer.
* Graphics
object cannot be used after
* dispose
has been called.
* Graphics
* 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.
* paint
and update
methods
* of components are automatically released by the system when
* those methods return. For efficiency, programmers should
* call dispose
when finished using
* a Graphics
object only if it was created
* directly from a component or another Graphics
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
* @since JDK1.0
*/
public abstract void dispose();
/**
* Disposes of this graphics context once it is no longer referenced.
* @see #dispose
* @since JDK1.0
*/
public void finalize() {
dispose();
}
/**
* Returns a String
object representing this
* Graphics
object's value.
* @return a string representation of this graphics context.
* @since JDK1.0
*/
public String toString() {
return getClass().getName() + "[font=" + getFont() + ",color=" + getColor() + "]";
}
/**
* @deprecated As of JDK version 1.1,
* replaced by getClipBounds()
.
*/
public Rectangle getClipRect() {
return getClipBounds();
}
}