001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2009, by Object Refinery Limited and Contributors.
006     *
007     * Project Info:  http://www.jfree.org/jfreechart/index.html
008     *
009     * This library is free software; you can redistribute it and/or modify it
010     * under the terms of the GNU Lesser General Public License as published by
011     * the Free Software Foundation; either version 2.1 of the License, or
012     * (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but
015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017     * License for more details.
018     *
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this library; if not, write to the Free Software
021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022     * USA.
023     *
024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025     * in the United States and other countries.]
026     *
027     * -------------------------
028     * GradientXYBarPainter.java
029     * -------------------------
030     * (C) Copyright 2008, 2009, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * Changes:
036     * --------
037     * 19-Jun-2008 : Version 1 (DG);
038     * 22-Feb-2009 : Fixed bug drawing outlines (DG);
039     *
040     */
041    
042    package org.jfree.chart.renderer.xy;
043    
044    import java.awt.Color;
045    import java.awt.GradientPaint;
046    import java.awt.Graphics2D;
047    import java.awt.Paint;
048    import java.awt.Stroke;
049    import java.awt.geom.Rectangle2D;
050    import java.awt.geom.RectangularShape;
051    import java.io.Serializable;
052    
053    import org.jfree.chart.HashUtilities;
054    import org.jfree.ui.RectangleEdge;
055    
056    /**
057     * An implementation of the {@link XYBarPainter} interface that uses several
058     * gradient fills to enrich the appearance of the bars.
059     *
060     * @since 1.0.11
061     */
062    public class GradientXYBarPainter implements XYBarPainter, Serializable {
063    
064        /** The division point between the first and second gradient regions. */
065        private double g1;
066    
067        /** The division point between the second and third gradient regions. */
068        private double g2;
069    
070        /** The division point between the third and fourth gradient regions. */
071        private double g3;
072    
073        /**
074         * Creates a new instance.
075         */
076        public GradientXYBarPainter() {
077            this(0.10, 0.20, 0.80);
078        }
079    
080        /**
081         * Creates a new instance.
082         *
083         * @param g1
084         * @param g2
085         * @param g3
086         */
087        public GradientXYBarPainter(double g1, double g2, double g3) {
088            this.g1 = g1;
089            this.g2 = g2;
090            this.g3 = g3;
091        }
092    
093        /**
094         * Paints a single bar instance.
095         *
096         * @param g2  the graphics target.
097         * @param renderer  the renderer.
098         * @param row  the row index.
099         * @param column  the column index.
100         * @param bar  the bar
101         * @param base  indicates which side of the rectangle is the base of the
102         *              bar.
103         */
104        public void paintBar(Graphics2D g2, XYBarRenderer renderer, int row,
105                int column, RectangularShape bar, RectangleEdge base) {
106    
107            Paint itemPaint = renderer.getItemPaint(row, column);
108    
109            Color c0, c1;
110            if (itemPaint instanceof Color) {
111                c0 = (Color) itemPaint;
112                c1 = c0.brighter();
113            }
114            else if (itemPaint instanceof GradientPaint) {
115                GradientPaint gp = (GradientPaint) itemPaint;
116                c0 = gp.getColor1();
117                c1 = gp.getColor2();
118            }
119            else {
120                c0 = Color.blue;
121                c1 = Color.blue.brighter();
122            }
123    
124            // as a special case, if the bar colour has alpha == 0, we draw
125            // nothing.
126            if (c0.getAlpha() == 0) {
127                return;
128            }
129    
130            if (base == RectangleEdge.TOP || base == RectangleEdge.BOTTOM) {
131                Rectangle2D[] regions = splitVerticalBar(bar, this.g1, this.g2,
132                        this.g3);
133                GradientPaint gp = new GradientPaint((float) regions[0].getMinX(),
134                        0.0f, c0, (float) regions[0].getMaxX(), 0.0f, Color.white);
135                g2.setPaint(gp);
136                g2.fill(regions[0]);
137    
138                gp = new GradientPaint((float) regions[1].getMinX(), 0.0f,
139                        Color.white, (float) regions[1].getMaxX(), 0.0f, c0);
140                g2.setPaint(gp);
141                g2.fill(regions[1]);
142    
143                gp = new GradientPaint((float) regions[2].getMinX(), 0.0f, c0,
144                        (float) regions[2].getMaxX(), 0.0f, c1);
145                g2.setPaint(gp);
146                g2.fill(regions[2]);
147    
148                gp = new GradientPaint((float) regions[3].getMinX(), 0.0f, c1,
149                         (float) regions[3].getMaxX(), 0.0f, c0);
150                g2.setPaint(gp);
151                g2.fill(regions[3]);
152            }
153            else if (base == RectangleEdge.LEFT || base == RectangleEdge.RIGHT) {
154                Rectangle2D[] regions = splitHorizontalBar(bar, this.g1, this.g2,
155                        this.g3);
156                GradientPaint gp = new GradientPaint(0.0f,
157                        (float) regions[0].getMinY(), c0, 0.0f,
158                        (float) regions[0].getMaxX(), Color.white);
159                g2.setPaint(gp);
160                g2.fill(regions[0]);
161    
162                gp = new GradientPaint(0.0f, (float) regions[1].getMinY(),
163                        Color.white, 0.0f, (float) regions[1].getMaxY(), c0);
164                g2.setPaint(gp);
165                g2.fill(regions[1]);
166    
167                gp = new GradientPaint(0.0f, (float) regions[2].getMinY(), c0,
168                        0.0f, (float) regions[2].getMaxY(), c1);
169                g2.setPaint(gp);
170                g2.fill(regions[2]);
171    
172                gp = new GradientPaint(0.0f, (float) regions[3].getMinY(), c1,
173                         0.0f, (float) regions[3].getMaxY(), c0);
174                g2.setPaint(gp);
175                g2.fill(regions[3]);
176    
177            }
178    
179            // draw the outline...
180            if (renderer.isDrawBarOutline()) {
181                Stroke stroke = renderer.getItemOutlineStroke(row, column);
182                Paint paint = renderer.getItemOutlinePaint(row, column);
183                if (stroke != null && paint != null) {
184                    g2.setStroke(stroke);
185                    g2.setPaint(paint);
186                    g2.draw(bar);
187                }
188            }
189    
190        }
191    
192        /**
193         * Paints a single bar instance.
194         *
195         * @param g2  the graphics target.
196         * @param renderer  the renderer.
197         * @param row  the row index.
198         * @param column  the column index.
199         * @param bar  the bar
200         * @param base  indicates which side of the rectangle is the base of the
201         *              bar.
202         * @param pegShadow  peg the shadow to the base of the bar?
203         */
204        public void paintBarShadow(Graphics2D g2, XYBarRenderer renderer, int row,
205                int column, RectangularShape bar, RectangleEdge base,
206                boolean pegShadow) {
207    
208            // handle a special case - if the bar colour has alpha == 0, it is
209            // invisible so we shouldn't draw any shadow
210            Paint itemPaint = renderer.getItemPaint(row, column);
211            if (itemPaint instanceof Color) {
212                Color c = (Color) itemPaint;
213                if (c.getAlpha() == 0) {
214                    return;
215                }
216            }
217    
218            RectangularShape shadow = createShadow(bar, renderer.getShadowXOffset(),
219                    renderer.getShadowYOffset(), base, pegShadow);
220            g2.setPaint(Color.gray);
221            g2.fill(shadow);
222    
223        }
224    
225        /**
226         * Creates a shadow for the bar.
227         *
228         * @param bar  the bar shape.
229         * @param xOffset  the x-offset for the shadow.
230         * @param yOffset  the y-offset for the shadow.
231         * @param base  the edge that is the base of the bar.
232         * @param pegShadow  peg the shadow to the base?
233         *
234         * @return A rectangle for the shadow.
235         */
236        private Rectangle2D createShadow(RectangularShape bar, double xOffset,
237                double yOffset, RectangleEdge base, boolean pegShadow) {
238            double x0 = bar.getMinX();
239            double x1 = bar.getMaxX();
240            double y0 = bar.getMinY();
241            double y1 = bar.getMaxY();
242            if (base == RectangleEdge.TOP) {
243                x0 += xOffset;
244                x1 += xOffset;
245                if (!pegShadow) {
246                    y0 += yOffset;
247                }
248                y1 += yOffset;
249            }
250            else if (base == RectangleEdge.BOTTOM) {
251                x0 += xOffset;
252                x1 += xOffset;
253                y0 += yOffset;
254                if (!pegShadow) {
255                    y1 += yOffset;
256                }
257            }
258            else if (base == RectangleEdge.LEFT) {
259                if (!pegShadow) {
260                    x0 += xOffset;
261                }
262                x1 += xOffset;
263                y0 += yOffset;
264                y1 += yOffset;
265            }
266            else if (base == RectangleEdge.RIGHT) {
267                x0 += xOffset;
268                if (!pegShadow) {
269                    x1 += xOffset;
270                }
271                y0 += yOffset;
272                y1 += yOffset;
273            }
274            return new Rectangle2D.Double(x0, y0, (x1 - x0), (y1 - y0));
275        }
276    
277        /**
278         * Splits a bar into subregions (elsewhere, these subregions will have
279         * different gradients applied to them).
280         *
281         * @param bar  the bar shape.
282         * @param a  the first division.
283         * @param b  the second division.
284         * @param c  the third division.
285         *
286         * @return An array containing four subregions.
287         */
288        private Rectangle2D[] splitVerticalBar(RectangularShape bar, double a,
289                double b, double c) {
290            Rectangle2D[] result = new Rectangle2D[4];
291            double x0 = bar.getMinX();
292            double x1 = Math.rint(x0 + (bar.getWidth() * a));
293            double x2 = Math.rint(x0 + (bar.getWidth() * b));
294            double x3 = Math.rint(x0 + (bar.getWidth() * c));
295            result[0] = new Rectangle2D.Double(bar.getMinX(), bar.getMinY(),
296                    x1 - x0, bar.getHeight());
297            result[1] = new Rectangle2D.Double(x1, bar.getMinY(), x2 - x1,
298                    bar.getHeight());
299            result[2] = new Rectangle2D.Double(x2, bar.getMinY(), x3 - x2,
300                    bar.getHeight());
301            result[3] = new Rectangle2D.Double(x3, bar.getMinY(),
302                    bar.getMaxX() - x3, bar.getHeight());
303            return result;
304        }
305    
306        /**
307         * Splits a bar into subregions (elsewhere, these subregions will have
308         * different gradients applied to them).
309         *
310         * @param bar  the bar shape.
311         * @param a  the first division.
312         * @param b  the second division.
313         * @param c  the third division.
314         *
315         * @return An array containing four subregions.
316         */
317        private Rectangle2D[] splitHorizontalBar(RectangularShape bar, double a,
318                double b, double c) {
319            Rectangle2D[] result = new Rectangle2D[4];
320            double y0 = bar.getMinY();
321            double y1 = Math.rint(y0 + (bar.getHeight() * a));
322            double y2 = Math.rint(y0 + (bar.getHeight() * b));
323            double y3 = Math.rint(y0 + (bar.getHeight() * c));
324            result[0] = new Rectangle2D.Double(bar.getMinX(), bar.getMinY(),
325                    bar.getWidth(), y1 - y0);
326            result[1] = new Rectangle2D.Double(bar.getMinX(), y1, bar.getWidth(),
327                    y2 - y1);
328            result[2] = new Rectangle2D.Double(bar.getMinX(), y2, bar.getWidth(),
329                    y3 - y2);
330            result[3] = new Rectangle2D.Double(bar.getMinX(), y3, bar.getWidth(),
331                    bar.getMaxY() - y3);
332            return result;
333        }
334    
335        /**
336         * Tests this instance for equality with an arbitrary object.
337         *
338         * @param obj  the obj (<code>null</code> permitted).
339         *
340         * @return A boolean.
341         */
342        public boolean equals(Object obj) {
343            if (obj == this) {
344                return true;
345            }
346            if (!(obj instanceof GradientXYBarPainter)) {
347                return false;
348            }
349            GradientXYBarPainter that = (GradientXYBarPainter) obj;
350            if (this.g1 != that.g1) {
351                return false;
352            }
353            if (this.g2 != that.g2) {
354                return false;
355            }
356            if (this.g3 != that.g3) {
357                return false;
358            }
359            return true;
360        }
361    
362        /**
363         * Returns a hash code for this instance.
364         *
365         * @return A hash code.
366         */
367        public int hashCode() {
368            int hash = 37;
369            hash = HashUtilities.hashCode(hash, this.g1);
370            hash = HashUtilities.hashCode(hash, this.g2);
371            hash = HashUtilities.hashCode(hash, this.g3);
372            return hash;
373        }
374    
375    }