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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package sun.awt.image;

import java.awt.image.DataBuffer;
import sun.java2d.SurfaceData;
import java.awt.Rectangle;

This class extends DataBuffer and allows access to native data via the DataBuffer methods. Note that, unlike other DataBuffer classes, the data is not stored in this class but has been created and stored elsewhere and this class is used merely to access that data. Note also that this class subclasses from DataBuffer and not from any of the standard subclasses (e.g., DataBufferInt); those subclasses allow the user to get a pointer to the data and manipulate it directly. That operation may not be possible or wise with native data. One important use of this DataBuffer class is in accessing the data stored in an offscreen vram surface, such as that created by the createVolatileImage() method. /**
 * This class extends {@code DataBuffer} and allows access to
 * native data via the DataBuffer methods.  Note that, unlike other
 * DataBuffer classes, the data is not stored in this class but
 * has been created and stored elsewhere and this class is used
 * merely to access that data.  Note also that this class subclasses
 * from DataBuffer and not from any of the standard subclasses
 * (e.g., DataBufferInt); those subclasses allow the user to
 * get a pointer to the data and manipulate it directly.  That
 * operation may not be possible or wise with native data.
 * One important use of this DataBuffer class is in accessing the
 * data stored in an offscreen vram surface, such as that created
 * by the createVolatileImage() method.
 */

public class DataBufferNative extends DataBuffer
{
    protected SurfaceData surfaceData;
    protected int width;

    
Constructor.  The constructor of this object requires a
SurfaceData object; that surfaceData object will be used
to access the actual pixel data in native code.
/**
     * Constructor.  The constructor of this object requires a
     * SurfaceData object; that surfaceData object will be used
     * to access the actual pixel data in native code.
     */
    public DataBufferNative(SurfaceData sData, int type, int width, int height) {
        super(type, width*height);
        this.width = width;
        this.surfaceData = sData;
    }

    protected native int getElem(int x, int y, SurfaceData sData);

    
getElem returns the pixel value for a given index into the
dataBuffer array.  The bank value is currently ignored (the
type of data accessed through this class is not stored in
separate banks).  The x and y coordinates of a pixel are calculated
from the index value and the native getElem() method is
called with the internal surfaceData object.
/**
     * getElem returns the pixel value for a given index into the
     * dataBuffer array.  The bank value is currently ignored (the
     * type of data accessed through this class is not stored in
     * separate banks).  The x and y coordinates of a pixel are calculated
     * from the index value and the native getElem() method is
     * called with the internal surfaceData object.
     */
    public int getElem(int bank, int i) {
        return getElem(i % width, i / width, surfaceData);
    }

    protected native void setElem(int x, int y, int val, SurfaceData sData);

    
setElem sets the pixel value of a given index into the
dataBuffer array.  The bank value is currently ignored (the
type of data accessed through this class is not stored in
separate banks).  The x and y coordinates of a pixel are calculated
from the index value and the native setElem() method is
called with the internal surfaceData object.
/**
     * setElem sets the pixel value of a given index into the
     * dataBuffer array.  The bank value is currently ignored (the
     * type of data accessed through this class is not stored in
     * separate banks).  The x and y coordinates of a pixel are calculated
     * from the index value and the native setElem() method is
     * called with the internal surfaceData object.
     */
    public void setElem(int bank, int i, int val) {
        setElem(i % width, i / width, val, surfaceData);
    }

}