001/* Copyright (C) 2000, 2002, 2004 Free Software Foundation 002 003This file is part of GNU Classpath. 004 005GNU Classpath is free software; you can redistribute it and/or modify 006it under the terms of the GNU General Public License as published by 007the Free Software Foundation; either version 2, or (at your option) 008any later version. 009 010GNU Classpath is distributed in the hope that it will be useful, but 011WITHOUT ANY WARRANTY; without even the implied warranty of 012MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 013General Public License for more details. 014 015You should have received a copy of the GNU General Public License 016along with GNU Classpath; see the file COPYING. If not, write to the 017Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01802110-1301 USA. 019 020Linking this library statically or dynamically with other modules is 021making a combined work based on this library. Thus, the terms and 022conditions of the GNU General Public License cover the whole 023combination. 024 025As a special exception, the copyright holders of this library give you 026permission to link this library with independent modules to produce an 027executable, regardless of the license terms of these independent 028modules, and to copy and distribute the resulting executable under 029terms of your choice, provided that you also meet, for each linked 030independent module, the terms and conditions of the license of that 031module. An independent module is a module which is not derived from 032or based on this library. If you modify this library, you may extend 033this exception to your version of the library, but you are not 034obligated to do so. If you do not wish to do so, delete this 035exception statement from your version. */ 036 037 038package java.awt.image; 039 040import gnu.java.awt.BitMaskExtent; 041 042import java.awt.Point; 043import java.awt.color.ColorSpace; 044 045/** 046 * @author Rolf W. Rasmussen (rolfwr@ii.uib.no) 047 */ 048public abstract class PackedColorModel extends ColorModel 049{ 050 private int masks[]; 051 052 /* Package accessibility, the DirectColorModel needs this array */ 053 int shifts[]; 054 055 public PackedColorModel(ColorSpace cspace, int pixelBits, 056 int[] colorMaskArray, int alphaMask, 057 boolean isAlphaPremultiplied, 058 int transparency, 059 int transferType) 060 { 061 super(pixelBits, calcBitsPerComponent(colorMaskArray, alphaMask), 062 cspace, (alphaMask != 0), isAlphaPremultiplied, transparency, 063 transferType); 064 initMasks(colorMaskArray, alphaMask); 065 if ((pixelBits<1) || (pixelBits>32)) { 066 throw new IllegalArgumentException("pixels per bits must be " + 067 "in the range [1, 32]"); 068 } 069 } 070 071 private static int[] calcBitsPerComponent(int[] colorMaskArray, 072 int alphaMask) 073 { 074 int numComponents = colorMaskArray.length; 075 if (alphaMask != 0) numComponents++; 076 077 int[] bitsPerComponent = new int[numComponents]; 078 079 BitMaskExtent extent = new BitMaskExtent(); 080 for (int b=0; b<colorMaskArray.length; b++) 081 { 082 extent.setMask(colorMaskArray[b]); 083 bitsPerComponent[b] = extent.bitWidth; 084 } 085 if (alphaMask != 0) 086 { 087 extent.setMask(alphaMask); 088 bitsPerComponent[numComponents-1] = extent.bitWidth; 089 } 090 return bitsPerComponent; 091 } 092 093 /** Initializes the masks. */ 094 private void initMasks(int[] colorMaskArray, int alphaMask) 095 { 096 int numComponents = colorMaskArray.length; 097 if (alphaMask == 0) 098 { 099 masks = colorMaskArray; 100 } 101 else 102 { 103 masks = new int[numComponents+1]; 104 System.arraycopy(colorMaskArray, 0, 105 masks, 0, 106 numComponents); 107 masks[numComponents++] = alphaMask; 108 } 109 110 shifts = new int[numComponents]; 111 112 // Bit field handling have been moved to a utility class 113 BitMaskExtent extent = new BitMaskExtent(); 114 for (int b=0; b<numComponents; b++) 115 { 116 extent.setMask(masks[b]); 117 shifts[b] = extent.leastSignificantBit; 118 } 119 } 120 121 public PackedColorModel(ColorSpace cspace, int pixelBits, 122 int rmask, int gmask, int bmask, 123 int amask, boolean isAlphaPremultiplied, 124 int transparency, 125 int transferType) 126 { 127 this(cspace, pixelBits, makeColorMaskArray(rmask, gmask, bmask), 128 amask, isAlphaPremultiplied, transparency, transferType); 129 } 130 131 /* TODO: If there is a alpha mask, it is inefficient to create a 132 color mask array that will be discarded when the alpha mask is 133 appended. We should probably create a private constructor that 134 takes a complete array of masks (color+alpha) as an 135 argument. */ 136 137 private static int[] makeColorMaskArray(int rmask, int gmask, int bmask) 138 { 139 int[] colorMaskArray = { rmask, gmask, bmask }; 140 return colorMaskArray; 141 } 142 143 public final int getMask(int index) 144 { 145 return masks[index]; 146 } 147 148 public final int[] getMasks() 149 { 150 return masks; 151 } 152 153 public SampleModel createCompatibleSampleModel(int w, int h) 154 { 155 return new SinglePixelPackedSampleModel(transferType, w, h, masks); 156 } 157 158 public boolean isCompatibleSampleModel(SampleModel sm) 159 { 160 if (!super.isCompatibleSampleModel(sm)) return false; 161 if (!(sm instanceof SinglePixelPackedSampleModel)) return false; 162 163 SinglePixelPackedSampleModel sppsm = 164 (SinglePixelPackedSampleModel) sm; 165 return java.util.Arrays.equals(sppsm.getBitMasks(), masks); 166 } 167 168 public WritableRaster getAlphaRaster(WritableRaster raster) { 169 if (!hasAlpha()) return null; 170 171 SampleModel sm = raster.getSampleModel(); 172 int[] alphaBand = { sm.getNumBands() - 1 }; 173 SampleModel alphaModel = sm.createSubsetSampleModel(alphaBand); 174 DataBuffer buffer = raster.getDataBuffer(); 175 Point origin = new Point(0, 0); 176 return Raster.createWritableRaster(alphaModel, buffer, origin); 177 } 178 179 public boolean equals(Object obj) 180 { 181 if (!super.equals(obj)) return false; 182 if (!(obj instanceof PackedColorModel)) return false; 183 184 PackedColorModel other = (PackedColorModel) obj; 185 186 return java.util.Arrays.equals(masks, other.masks); 187 } 188}