Java example source code file (MaskBlit.java)

This example Java source code file (MaskBlit.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

awt, cannot, compositetype, general, graphicsprimitive, internalerror, java2d, maskblit, region, rendercache, string, surfacedata, surfacetype, tracemaskblit, weakreference, xor

The MaskBlit.java Java example source code

/*
 * Copyright (c) 1999, 2004, 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package sun.java2d.loops;

import java.awt.Composite;
import java.lang.ref.WeakReference;
import sun.java2d.loops.GraphicsPrimitive;
import sun.java2d.SurfaceData;
import sun.java2d.pipe.Region;

/**
 * MaskBlit
 * 1) copies rectangle of pixels from one surface to another
 * 2) performs compositing of colors based upon a Composite
 *    parameter
 * 3) blends result of composite with destination using an
 *    alpha coverage mask
 * 4) the mask may be null in which case it should be treated
 *    as if it were an array of all opaque values (0xff)
 *
 * precise behavior is undefined if the source surface
 * and the destination surface are the same surface
 * with overlapping regions of pixels
 */

public class MaskBlit extends GraphicsPrimitive
{
    public static final String methodSignature = "MaskBlit(...)".toString();

    public static final int primTypeID = makePrimTypeID();

    private static RenderCache blitcache = new RenderCache(20);

    public static MaskBlit locate(SurfaceType srctype,
                                  CompositeType comptype,
                                  SurfaceType dsttype)
    {
        return (MaskBlit)
            GraphicsPrimitiveMgr.locate(primTypeID,
                                        srctype, comptype, dsttype);
    }

    public static MaskBlit getFromCache(SurfaceType src,
                                        CompositeType comp,
                                        SurfaceType dst)
    {
        Object o = blitcache.get(src, comp, dst);
        if (o != null) {
            return (MaskBlit) o;
        }
        MaskBlit blit = locate(src, comp, dst);
        if (blit == null) {
            System.out.println("mask blit loop not found for:");
            System.out.println("src:  "+src);
            System.out.println("comp: "+comp);
            System.out.println("dst:  "+dst);
        } else {
            blitcache.put(src, comp, dst, blit);
        }
        return blit;
    }

    protected MaskBlit(SurfaceType srctype,
                       CompositeType comptype,
                       SurfaceType dsttype)
    {
        super(methodSignature, primTypeID, srctype, comptype, dsttype);
    }

    public MaskBlit(long pNativePrim,
                    SurfaceType srctype,
                    CompositeType comptype,
                    SurfaceType dsttype)
    {
        super(pNativePrim, methodSignature, primTypeID, srctype, comptype, dsttype);
    }

    /**
     * All MaskBlit implementors must have this invoker method
     */
    public native void MaskBlit(SurfaceData src, SurfaceData dst,
                                Composite comp, Region clip,
                                int srcx, int srcy,
                                int dstx, int dsty,
                                int width, int height,
                                byte[] mask, int maskoff, int maskscan);

    static {
        GraphicsPrimitiveMgr.registerGeneral(new MaskBlit(null, null, null));
    }

    public GraphicsPrimitive makePrimitive(SurfaceType srctype,
                                           CompositeType comptype,
                                           SurfaceType dsttype)
    {
        /*
        new Throwable().printStackTrace();
        System.out.println("Constructing general maskblit for:");
        System.out.println("src:  "+srctype);
        System.out.println("comp: "+comptype);
        System.out.println("dst:  "+dsttype);
        */

        if (CompositeType.Xor.equals(comptype)) {
            throw new InternalError("Cannot construct MaskBlit for " +
                                    "XOR mode");
        }

        General ob = new General(srctype, comptype, dsttype);
        setupGeneralBinaryOp(ob);
        return ob;
    }

    private static class General
        extends MaskBlit
        implements GeneralBinaryOp
    {
        Blit convertsrc;
        Blit convertdst;
        MaskBlit performop;
        Blit convertresult;

        WeakReference srcTmp;
        WeakReference dstTmp;

        public General(SurfaceType srctype,
                       CompositeType comptype,
                       SurfaceType dsttype)
        {
            super(srctype, comptype, dsttype);
        }

        public void setPrimitives(Blit srcconverter,
                                  Blit dstconverter,
                                  GraphicsPrimitive genericop,
                                  Blit resconverter)
        {
            this.convertsrc = srcconverter;
            this.convertdst = dstconverter;
            this.performop = (MaskBlit) genericop;
            this.convertresult = resconverter;
        }

        public synchronized void MaskBlit(SurfaceData srcData,
                                          SurfaceData dstData,
                                          Composite comp,
                                          Region clip,
                                          int srcx, int srcy,
                                          int dstx, int dsty,
                                          int width, int height,
                                          byte mask[], int offset, int scan)
        {
            SurfaceData src, dst;
            Region opclip;
            int sx, sy, dx, dy;

            if (convertsrc == null) {
                src = srcData;
                sx = srcx;
                sy = srcy;
            } else {
                SurfaceData cachedSrc = null;
                if (srcTmp != null) {
                    cachedSrc = (SurfaceData) srcTmp.get();
                }
                src = convertFrom(convertsrc, srcData, srcx, srcy,
                                  width, height, cachedSrc);
                sx = 0;
                sy = 0;
                if (src != cachedSrc) {
                    srcTmp = new WeakReference(src);
                }
            }

            if (convertdst == null) {
                dst = dstData;
                dx = dstx;
                dy = dsty;
                opclip = clip;
            } else {
                // assert: convertresult != null
                SurfaceData cachedDst = null;
                if (dstTmp != null) {
                    cachedDst = (SurfaceData) dstTmp.get();
                }
                dst = convertFrom(convertdst, dstData, dstx, dsty,
                                  width, height, cachedDst);
                dx = 0;
                dy = 0;
                opclip = null;
                if (dst != cachedDst) {
                    dstTmp = new WeakReference(dst);
                }
            }

            performop.MaskBlit(src, dst, comp, opclip,
                               sx, sy, dx, dy, width, height,
                               mask, offset, scan);

            if (convertresult != null) {
                // assert: convertdst != null
                convertTo(convertresult, dst, dstData, clip,
                          dstx, dsty, width, height);
            }
        }
    }

    public GraphicsPrimitive traceWrap() {
        return new TraceMaskBlit(this);
    }

    private static class TraceMaskBlit extends MaskBlit {
        MaskBlit target;

        public TraceMaskBlit(MaskBlit target) {
            // We need to have the same NativePrim as our
            // target in case we are used with a TransformHelper
            super(target.getNativePrim(),
                  target.getSourceType(),
                  target.getCompositeType(),
                  target.getDestType());
            this.target = target;
        }

        public GraphicsPrimitive traceWrap() {
            return this;
        }

        public void MaskBlit(SurfaceData src, SurfaceData dst,
                             Composite comp, Region clip,
                             int srcx, int srcy, int dstx, int dsty,
                             int width, int height,
                             byte[] mask, int maskoff, int maskscan)
        {
            tracePrimitive(target);
            target.MaskBlit(src, dst, comp, clip,
                            srcx, srcy, dstx, dsty, width, height,
                            mask, maskoff, maskscan);
        }
    }
}