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

/*
 * Copyright 1997-2007 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.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</code> 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</code>
 * object should be small because the <code>BufferedImage</code> data
 * is copied by the <code>TexturePaint</code> 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</code> infinitely in all directions
 * in user space and mapping the <code>BufferedImage</code> to each
 * replicated <code>Rectangle2D</code>.
 * @see Paint
 * @see Graphics2D#setPaint
 */

public class TexturePaint implements Paint {

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

    /**
     * Constructs a <code>TexturePaint</code> object.
     * @param txtr the <code>BufferedImage</code> object with the texture
     * used for painting
     * @param anchor the <code>Rectangle2D</code> 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</code> texture used to
     * fill the shapes.
     * @return a <code>BufferedImage</code>.
     */
    public BufferedImage getImage() {
        return bufImg;
    }

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

    /**
     * Creates and returns a context used to generate the color pattern.
     * @param cm the {@link ColorModel} that receives the
     * <code>Paint</code> data. This is used only as a hint.
     * @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 a {@link RenderingHints} object that can be used to
     *          specify how the pattern is ultimately rendered
     * @return the {@link PaintContext} used for generating color
     *          patterns.
     * @see PaintContext
     */
    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</code>.
     * @return the transparency mode for this <code>TexturePaint</code>
     * as an integer value.
     * @see Transparency
     */
    public int getTransparency() {
        return (bufImg.getColorModel()).getTransparency();
    }

}