com.jcraft.weirdx.TransparentFilter.java Source code

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Here is the source code for com.jcraft.weirdx.TransparentFilter.java

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/* -*-mode:java; c-basic-offset:2; -*- */
/* WeirdX - This class is used in clipping-pixmap operation.
 *
 * Copyright (C) 1999-2004 JCraft, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

package com.jcraft.weirdx;

import java.awt.Image;
import java.awt.image.ImageObserver;
import java.awt.image.PixelGrabber;
import java.awt.image.RGBImageFilter;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

final class TransparentFilter extends RGBImageFilter {
    private static Log LOG = LogFactory.getLog(TransparentFilter.class);

    int width;
    int height;
    byte[] pixels;
    int cx;
    int cy;

    TransparentFilter(int cx, int cy, XPixmap pixmap) {
        this.cx = cx;
        this.cy = cy;

        this.width = pixmap.width;
        this.height = pixmap.height;

        pixels = new byte[pixmap.width * pixmap.height];
        if (pixmap.data != null) {
            for (int i = 0; i < pixmap.height; i++) {
                for (int j = 0; j < pixmap.width; j++) {
                    if (pixmap.data[i * pixmap.width + j] == 0) {
                        pixels[i * pixmap.width + j] = 0;
                    } else {
                        pixels[i * pixmap.width + j] = 1;
                    }
                }
            }
        } else {
            int[] ipixels = new int[pixmap.width * pixmap.height];
            Image img = pixmap.img;
            PixelGrabber pg = null;
            pg = new PixelGrabber(img, 0, 0, pixmap.width, pixmap.height, ipixels, 0, pixmap.width);
            try {
                pg.grabPixels();
            } catch (InterruptedException e) {
                //System.err.println("interrupted waiting for pixels!");
                return;
            }

            if ((pg.getStatus() & ImageObserver.ABORT) != 0) {
                LOG.error("image fetch aborted or errored");
                return;
            }

            for (int i = 0; i < pixmap.height; i++) {
                for (int j = 0; j < pixmap.width; j++) {
                    if (ipixels[i * pixmap.width + j] == 0xff000000) {
                        pixels[i * pixmap.width + j] = 0;
                    } else {
                        pixels[i * pixmap.width + j] = 1;
                    }
                }
            }
            ipixels = null;
        }
    }

    public int filterRGB(int x, int y, int rgb) {
        if (cx <= x && x < cx + width && cy <= y && y < cy + height) {
            if (pixels[(y - cy) * width + (x - cx)] == 0)
                rgb = 0x00ffffff;
        }
        return rgb;
    }
}