/*

 * Copyright (c) 2000, 2001, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 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 <CODE>DataBuffer</CODE> 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

     * 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);

    }

}