1 /*
   2  * Copyright (c) 2000, 2001, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 
  27 package sun.awt.image;
  28 
  29 import java.awt.image.DataBuffer;
  30 import sun.java2d.SurfaceData;
  31 import java.awt.Rectangle;
  32 
  33 /**
  34  * This class extends {@code DataBuffer} and allows access to
  35  * native data via the DataBuffer methods.  Note that, unlike other
  36  * DataBuffer classes, the data is not stored in this class but
  37  * has been created and stored elsewhere and this class is used
  38  * merely to access that data.  Note also that this class subclasses
  39  * from DataBuffer and not from any of the standard subclasses
  40  * (e.g., DataBufferInt); those subclasses allow the user to
  41  * get a pointer to the data and manipulate it directly.  That
  42  * operation may not be possible or wise with native data.
  43  * One important use of this DataBuffer class is in accessing the
  44  * data stored in an offscreen vram surface, such as that created
  45  * by the createVolatileImage() method.
  46  */
  47 
  48 public class DataBufferNative extends DataBuffer
  49 {
  50     protected SurfaceData surfaceData;
  51     protected int width;
  52 
  53     /**
  54      * Constructor.  The constructor of this object requires a
  55      * SurfaceData object; that surfaceData object will be used
  56      * to access the actual pixel data in native code.
  57      */
  58     public DataBufferNative(SurfaceData sData, int type, int width, int height) {
  59         super(type, width*height);
  60         this.width = width;
  61         this.surfaceData = sData;
  62     }
  63 
  64     protected native int getElem(int x, int y, SurfaceData sData);
  65 
  66     /**
  67      * getElem returns the pixel value for a given index into the
  68      * dataBuffer array.  The bank value is currently ignored (the
  69      * type of data accessed through this class is not stored in
  70      * separate banks).  The x and y coordinates of a pixel are calculated
  71      * from the index value and the native getElem() method is
  72      * called with the internal surfaceData object.
  73      */
  74     public int getElem(int bank, int i) {
  75         return getElem(i % width, i / width, surfaceData);
  76     }
  77 
  78     protected native void setElem(int x, int y, int val, SurfaceData sData);
  79 
  80     /**
  81      * setElem sets the pixel value of a given index into the
  82      * dataBuffer array.  The bank value is currently ignored (the
  83      * type of data accessed through this class is not stored in
  84      * separate banks).  The x and y coordinates of a pixel are calculated
  85      * from the index value and the native setElem() method is
  86      * called with the internal surfaceData object.
  87      */
  88     public void setElem(int bank, int i, int val) {
  89         setElem(i % width, i / width, val, surfaceData);
  90     }
  91 
  92 }
--- EOF ---