1/* 2 * Copyright (c) 1996, 2007, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package sun.awt.image; 27 28import java.awt.Component; 29import java.awt.Color; 30import java.awt.SystemColor; 31import java.awt.Font; 32import java.awt.Graphics; 33import java.awt.Graphics2D; 34import java.awt.GraphicsEnvironment; 35import java.awt.image.BufferedImage; 36import java.awt.image.ImageProducer; 37import java.awt.image.ColorModel; 38import java.awt.image.WritableRaster; 39import sun.java2d.SunGraphics2D; 40import sun.java2d.SurfaceData; 41 42/** 43 * This is a special variant of BufferedImage that keeps a reference to 44 * a Component. The Component's foreground and background colors and 45 * default font are used as the defaults for this image. 46 */ 47public class OffScreenImage extends BufferedImage { 48 49 protected Component c; 50 private OffScreenImageSource osis; 51 private Font defaultFont; 52 53 /** 54 * Constructs an OffScreenImage given a color model and tile, 55 * for offscreen rendering to be used with a given component. 56 * The component is used to obtain the foreground color, background 57 * color and font. 58 */ 59 public OffScreenImage(Component c, ColorModel cm, WritableRaster raster, 60 boolean isRasterPremultiplied) 61 { 62 super(cm, raster, isRasterPremultiplied, null); 63 this.c = c; 64 initSurface(raster.getWidth(), raster.getHeight()); 65 } 66 67 public Graphics getGraphics() { 68 return createGraphics(); 69 } 70 71 public Graphics2D createGraphics() { 72 if (c == null) { 73 GraphicsEnvironment env = 74 GraphicsEnvironment.getLocalGraphicsEnvironment(); 75 return env.createGraphics(this); 76 } 77 78 Color bg = c.getBackground(); 79 if (bg == null) { 80 bg = SystemColor.window; 81 } 82 83 Color fg = c.getForeground(); 84 if (fg == null) { 85 fg = SystemColor.windowText; 86 } 87 88 Font font = c.getFont(); 89 if (font == null) { 90 if (defaultFont == null) { 91 defaultFont = new Font("Dialog", Font.PLAIN, 12); 92 } 93 font = defaultFont; 94 } 95 96 return new SunGraphics2D(SurfaceData.getPrimarySurfaceData(this), 97 fg, bg, font); 98 } 99 100 private void initSurface(int width, int height) { 101 Graphics2D g2 = createGraphics(); 102 try { 103 g2.clearRect(0, 0, width, height); 104 } finally { 105 g2.dispose(); 106 } 107 } 108 109 public ImageProducer getSource() { 110 if (osis == null) { 111 osis = new OffScreenImageSource(this); 112 } 113 return osis; 114 } 115} 116