src/java.desktop/share/classes/java/awt/TexturePaint.java

/*
 * Copyright (c) 1997, 2008, 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 java.awt;

import java.awt.geom.Rectangle2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;

/**
 * The {@code TexturePaint} class provides a way to fill a
 * {@link Shape} with a texture that is specified as
 * a {@link BufferedImage}. The size of the {@code BufferedImage}
 * object should be small because the {@code BufferedImage} data
 * is copied by the {@code TexturePaint} object.
 * At construction time, the texture is anchored to the upper
 * left corner of a {@link Rectangle2D} that is
 * specified in user space.  Texture is computed for
 * locations in the device space by conceptually replicating the
 * specified {@code Rectangle2D} infinitely in all directions
 * in user space and mapping the {@code BufferedImage} to each
 * replicated {@code Rectangle2D}.
 * @see Paint
 * @see Graphics2D#setPaint
 * @version 1.48, 06/05/07
 */

public class TexturePaint implements Paint {

    BufferedImage bufImg;
    double tx;
    double ty;
    double sx;
    double sy;

    /**
     * Constructs a {@code TexturePaint} object.
     * @param txtr the {@code BufferedImage} object with the texture
     * used for painting
     * @param anchor the {@code Rectangle2D} in user space used to
     * anchor and replicate the texture
     */
    public TexturePaint(BufferedImage txtr,
                        Rectangle2D anchor) {
        this.bufImg = txtr;
        this.tx = anchor.getX();
        this.ty = anchor.getY();
        this.sx = anchor.getWidth() / bufImg.getWidth();
        this.sy = anchor.getHeight() / bufImg.getHeight();
    }

    /**
     * Returns the {@code BufferedImage} texture used to
     * fill the shapes.
     * @return a {@code BufferedImage}.
     */
    public BufferedImage getImage() {
        return bufImg;
    }

    /**
     * Returns a copy of the anchor rectangle which positions and
     * sizes the textured image.
     * @return the {@code Rectangle2D} used to anchor and
     * size this {@code TexturePaint}.
     */
    public Rectangle2D getAnchorRect() {
        return new Rectangle2D.Double(tx, ty,
                                      sx * bufImg.getWidth(),
                                      sy * bufImg.getHeight());
    }

    /**
     * Creates and returns a {@link PaintContext} used to
     * generate a tiled image pattern.
     * See the {@link Paint#createContext specification} of the
     * method in the {@link Paint} interface for information
     * on null parameter handling.
     *
     * @param cm the preferred {@link ColorModel} which represents the most convenient
     *           format for the caller to receive the pixel data, or {@code null}
     *           if there is no preference.
     * @param deviceBounds the device space bounding box
     *                     of the graphics primitive being rendered.
     * @param userBounds the user space bounding box
     *                   of the graphics primitive being rendered.
     * @param xform the {@link AffineTransform} from user
     *              space into device space.
     * @param hints the set of hints that the context object can use to
     *              choose between rendering alternatives.
     * @return the {@code PaintContext} for
     *         generating color patterns.
     * @see Paint
     * @see PaintContext
     * @see ColorModel
     * @see Rectangle
     * @see Rectangle2D
     * @see AffineTransform
     * @see RenderingHints
     */
    public PaintContext createContext(ColorModel cm,
                                      Rectangle deviceBounds,
                                      Rectangle2D userBounds,
                                      AffineTransform xform,
                                      RenderingHints hints) {
        if (xform == null) {
            xform = new AffineTransform();
        } else {
            xform = (AffineTransform) xform.clone();
        }
        xform.translate(tx, ty);
        xform.scale(sx, sy);

        return TexturePaintContext.getContext(bufImg, xform, hints,
                                              deviceBounds);
    }

    /**
     * Returns the transparency mode for this {@code TexturePaint}.
     * @return the transparency mode for this {@code TexturePaint}
     * as an integer value.
     * @see Transparency
     */
    public int getTransparency() {
        return (bufImg.getColorModel()).getTransparency();
    }

}