TrakEM2_/src/main/java/ini/trakem2/display/graphics/SubtractARGBComposite.java

   1 /**
   2  * License: GPL
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License 2
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  16  */
  17 package ini.trakem2.display.graphics;
  18
  19 import java.awt.Composite;
  20 import java.awt.CompositeContext;
  21 import java.awt.RenderingHints;
  22 import java.awt.image.ColorModel;
  23 import java.awt.image.Raster;
  24 import java.awt.image.WritableRaster;
  25
  26 import mpicbg.util.Util;
  27
  28 /**
  29  *
  30  * @author Stephan Saalfeld <saalfeld@mpi-cbg.de>
  31  * @version 0.1b
  32  */
  33 public class SubtractARGBComposite implements Composite
  34 {
  35         static private interface Composer
  36         {
  37                 public void compose( final int[] src, final int[] dst, final float alpha );
  38         }
  39         final static private class ARGB2ARGB implements Composer
  40         {
  41                 final public void compose( final int[] src, final int[] dst, final float alpha )
  42                 {
  43                         final float srcAlpha = src[ 3 ] / 255.0f * alpha;
  44
  45                         dst[ 0 ] = Math.max( 0, Util.round( dst[ 0 ] - src[ 0 ] * srcAlpha ) );
  46                         dst[ 1 ] = Math.max( 0, Util.round( dst[ 1 ] - src[ 1 ] * srcAlpha ) );
  47                         dst[ 2 ] = Math.max( 0, Util.round( dst[ 2 ] - src[ 2 ] * srcAlpha ) );
  48                         dst[ 3 ] = 255;
  49                 }
  50         }
  51         final static private class RGB2ARGB implements Composer
  52         {
  53                 final public void compose( final int[] src, final int[] dst, final float alpha )
  54                 {
  55                         dst[ 0 ] = Math.max( 0, Util.round( dst[ 0 ] - src[ 0 ] * alpha ) );
  56                         dst[ 1 ] = Math.max( 0, Util.round( dst[ 1 ] - src[ 1 ] * alpha ) );
  57                         dst[ 2 ] = Math.max( 0, Util.round( dst[ 2 ] - src[ 2 ] * alpha ) );
  58                         dst[ 3 ] = 255;
  59                 }
  60         }
  61         final static private class Gray2ARGB implements Composer
  62         {
  63                 final public void compose( final int[] src, final int[] dst, final float alpha )
  64                 {
  65                         dst[ 0 ] = Math.max( 0, Util.round( dst[ 0 ] - src[ 0 ] * alpha ) );
  66                         dst[ 1 ] = Math.max( 0, Util.round( dst[ 1 ] - src[ 0 ] * alpha ) );
  67                         dst[ 2 ] = Math.max( 0, Util.round( dst[ 2 ] - src[ 0 ] * alpha ) );
  68                         dst[ 3 ] = 255;
  69                 }
  70         }
  71
  72         static private SubtractARGBComposite instance = new SubtractARGBComposite();
  73
  74         final private float alpha;
  75
  76         public static SubtractARGBComposite getInstance( final float alpha )
  77         {
  78                 if ( alpha == 1.0f ) { return instance; }
  79                 return new SubtractARGBComposite( alpha );
  80         }
  81
  82         private SubtractARGBComposite()
  83         {
  84                 this.alpha = 1.0f;
  85         }
  86
  87         private SubtractARGBComposite( final float alpha )
  88         {
  89                 this.alpha = alpha;
  90         }
  91
  92         public CompositeContext createContext( ColorModel srcColorModel, ColorModel dstColorModel, RenderingHints hints )
  93         {
  94                 final Composer c;
  95                 if ( srcColorModel.getNumColorComponents() > 1 )
  96                 {
  97                         if ( srcColorModel.hasAlpha() )
  98                                 c = new ARGB2ARGB();
  99                         else
 100                                 c = new RGB2ARGB();
 101                 }
 102                 else
 103                         c = new Gray2ARGB();
 104
 105                 return new CompositeContext()
 106                 {
 107                         private Composer composer = c;
 108                         public void compose( Raster src, Raster dstIn, WritableRaster dstOut )
 109                         {
 110                                 final int[] srcPixel = new int[ 4 ];
 111                                 final int[] dstInPixel = new int[ 4 ];
 112
 113                                 for ( int x = 0; x < dstOut.getWidth(); x++ )
 114                                 {
 115                                         for ( int y = 0; y < dstOut.getHeight(); y++ )
 116                                         {
 117                                                 src.getPixel( x, y, srcPixel );
 118                                                 dstIn.getPixel( x, y, dstInPixel );
 119
 120                                                 composer.compose( srcPixel, dstInPixel, alpha );
 121
 122                                                 dstOut.setPixel( x, y, dstInPixel );
 123                                         }
 124                                 }
 125                         }
 126
 127                         public void dispose()
 128                         {}
 129                 };
 130         }
 131 }