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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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*
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package sun.awt.image;
import java.awt.image.DataBuffer;
import sun.java2d.SurfaceData;
import java.awt.Rectangle;
/**
* 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.
*/
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.
*/
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
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