WritableRasterNative.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package sun.awt.image;

import java.awt.Point;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.DataBuffer;
import java.awt.image.DirectColorModel;
import java.awt.image.PixelInterleavedSampleModel;
import java.awt.image.SampleModel;
import java.awt.image.SinglePixelPackedSampleModel;
import java.awt.image.WritableRaster;
import sun.java2d.SurfaceData;

/**
 * WritableRasterNative
 * This class exists to wrap a native DataBuffer object.  The
 * standard WritableRaster object assumes that a DataBuffer
 * of a given type (e.g., DataBuffer.TYPE_INT) implies a certain
 * subclass (e.g., DataBufferInt).  But this is not always the
 * case.  DataBufferNative, for example, may allow access to 
 * integer-based data, but it is not DataBufferInt (which is a 
 * final class and cannot be subclassed).
 * So this class exists simply to allow the WritableRaster
 * functionality for this new kind of DataBuffer object.
 */
public class WritableRasterNative extends WritableRaster {

    public static WritableRasterNative createNativeRaster(SampleModel sm, 
							  DataBuffer db) 
    {
	return new WritableRasterNative(sm, db);
    }

    protected WritableRasterNative(SampleModel sm, DataBuffer db) {
	super(sm, db, new Point(0, 0));
    }

    public static WritableRasterNative createNativeRaster(ColorModel cm, 
							  SurfaceData sd, 
							  int width, 
							  int height)
    {
	SampleModel smHw = null;
	int dataType = 0;
	int scanStride = width;

	switch (cm.getPixelSize()) {
	case 8:
	case 12:
	    // 8-bits uses PixelInterleavedSampleModel
	    if (cm.getPixelSize() == 8) {
		dataType = DataBuffer.TYPE_BYTE;
	    } else {
		dataType = DataBuffer.TYPE_USHORT;
	    }
	    int[] bandOffsets = new int[1];
	    bandOffsets[0] = 0;
	    smHw = new PixelInterleavedSampleModel(dataType, width,
						   height, 
						   1, scanStride,
						   bandOffsets);
	    break;

	    // all others use SinglePixelPackedSampleModel
	case 15:
	case 16:
	    dataType = DataBuffer.TYPE_USHORT;
	    int[] bitMasks = new int[3];
	    DirectColorModel dcm = (DirectColorModel)cm;
	    bitMasks[0] = dcm.getRedMask();
 	    bitMasks[1] = dcm.getGreenMask();
	    bitMasks[2] = dcm.getBlueMask();
	    smHw = new SinglePixelPackedSampleModel(dataType, width, 
						    height, scanStride, 
						    bitMasks);
	    break;
	case 24:
	case 32:
	    dataType = DataBuffer.TYPE_INT;
	    bitMasks = new int[3];
	    dcm = (DirectColorModel)cm;
	    bitMasks[0] = dcm.getRedMask();
	    bitMasks[1] = dcm.getGreenMask();
	    bitMasks[2] = dcm.getBlueMask();
	    smHw = new SinglePixelPackedSampleModel(dataType, width, 
						    height, scanStride, 
						    bitMasks);
	    break;
	default:
	    throw new InternalError("Unsupported depth " + 
				    cm.getPixelSize());
	}

	DataBuffer dbn = new DataBufferNative(sd, dataType, 
					      width, height);
	return new WritableRasterNative(smHw, dbn);
    }
}