jdk/src/share/classes/javax/swing/border/TitledBorder.java
changeset 2 90ce3da70b43
child 463 435cd1cc42b6
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/javax/swing/border/TitledBorder.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,746 @@
+/*
+ * 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 javax.swing.border;
+
+import sun.swing.SwingUtilities2;
+
+import java.awt.Graphics;
+import java.awt.Insets;
+import java.awt.Rectangle;
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.FontMetrics;
+import java.awt.Point;
+import java.awt.Toolkit;
+import java.awt.Component;
+import java.awt.Dimension;
+import java.beans.ConstructorProperties;
+
+import javax.swing.JComponent;
+import javax.swing.UIManager;
+
+/**
+ * A class which implements an arbitrary border
+ * with the addition of a String title in a
+ * specified position and justification.
+ * <p>
+ * If the border, font, or color property values are not
+ * specified in the constuctor or by invoking the appropriate
+ * set methods, the property values will be defined by the current
+ * look and feel, using the following property names in the
+ * Defaults Table:
+ * <ul>
+ * <li>&quot;TitledBorder.border&quot;
+ * <li>&quot;TitledBorder.font&quot;
+ * <li>&quot;TitledBorder.titleColor&quot;
+ * </ul>
+ * <p>
+ * <strong>Warning:</strong>
+ * Serialized objects of this class will not be compatible with
+ * future Swing releases. The current serialization support is
+ * appropriate for short term storage or RMI between applications running
+ * the same version of Swing.  As of 1.4, support for long term storage
+ * of all JavaBeans<sup><font size="-2">TM</font></sup>
+ * has been added to the <code>java.beans</code> package.
+ * Please see {@link java.beans.XMLEncoder}.
+ *
+ * @author David Kloba
+ * @author Amy Fowler
+ */
+public class TitledBorder extends AbstractBorder
+{
+    protected String title;
+    protected Border border;
+    protected int    titlePosition;
+    protected int    titleJustification;
+    protected Font   titleFont;
+    protected Color  titleColor;
+
+    private Point textLoc = new Point();
+
+    /**
+     * Use the default vertical orientation for the title text.
+     */
+    static public final int     DEFAULT_POSITION        = 0;
+    /** Position the title above the border's top line. */
+    static public final int     ABOVE_TOP       = 1;
+    /** Position the title in the middle of the border's top line. */
+    static public final int     TOP             = 2;
+    /** Position the title below the border's top line. */
+    static public final int     BELOW_TOP       = 3;
+    /** Position the title above the border's bottom line. */
+    static public final int     ABOVE_BOTTOM    = 4;
+    /** Position the title in the middle of the border's bottom line. */
+    static public final int     BOTTOM          = 5;
+    /** Position the title below the border's bottom line. */
+    static public final int     BELOW_BOTTOM    = 6;
+
+    /**
+     * Use the default justification for the title text.
+     */
+    static public final int     DEFAULT_JUSTIFICATION   = 0;
+    /** Position title text at the left side of the border line. */
+    static public final int     LEFT    = 1;
+    /** Position title text in the center of the border line. */
+    static public final int     CENTER  = 2;
+    /** Position title text at the right side of the border line. */
+    static public final int     RIGHT   = 3;
+    /** Position title text at the left side of the border line
+     *  for left to right orientation, at the right side of the
+     *  border line for right to left orientation.
+     */
+    static public final int     LEADING = 4;
+    /** Position title text at the right side of the border line
+     *  for left to right orientation, at the left side of the
+     *  border line for right to left orientation.
+     */
+    static public final int     TRAILING = 5;
+
+    // Space between the border and the component's edge
+    static protected final int EDGE_SPACING = 2;
+
+    // Space between the border and text
+    static protected final int TEXT_SPACING = 2;
+
+    // Horizontal inset of text that is left or right justified
+    static protected final int TEXT_INSET_H = 5;
+
+    /**
+     * Creates a TitledBorder instance.
+     *
+     * @param title  the title the border should display
+     */
+    public TitledBorder(String title)     {
+        this(null, title, LEADING, TOP, null, null);
+    }
+
+    /**
+     * Creates a TitledBorder instance with the specified border
+     * and an empty title.
+     *
+     * @param border  the border
+     */
+    public TitledBorder(Border border)       {
+        this(border, "", LEADING, TOP, null, null);
+    }
+
+    /**
+     * Creates a TitledBorder instance with the specified border
+     * and title.
+     *
+     * @param border  the border
+     * @param title  the title the border should display
+     */
+    public TitledBorder(Border border, String title) {
+        this(border, title, LEADING, TOP, null, null);
+    }
+
+    /**
+     * Creates a TitledBorder instance with the specified border,
+     * title, title-justification, and title-position.
+     *
+     * @param border  the border
+     * @param title  the title the border should display
+     * @param titleJustification the justification for the title
+     * @param titlePosition the position for the title
+     */
+    public TitledBorder(Border border,
+                        String title,
+                        int titleJustification,
+                        int titlePosition)      {
+        this(border, title, titleJustification,
+                        titlePosition, null, null);
+    }
+
+    /**
+     * Creates a TitledBorder instance with the specified border,
+     * title, title-justification, title-position, and title-font.
+     *
+     * @param border  the border
+     * @param title  the title the border should display
+     * @param titleJustification the justification for the title
+     * @param titlePosition the position for the title
+     * @param titleFont the font for rendering the title
+     */
+    public TitledBorder(Border border,
+                        String title,
+                        int titleJustification,
+                        int titlePosition,
+                        Font titleFont) {
+        this(border, title, titleJustification,
+                        titlePosition, titleFont, null);
+    }
+
+    /**
+     * Creates a TitledBorder instance with the specified border,
+     * title, title-justification, title-position, title-font, and
+     * title-color.
+     *
+     * @param border  the border
+     * @param title  the title the border should display
+     * @param titleJustification the justification for the title
+     * @param titlePosition the position for the title
+     * @param titleFont the font of the title
+     * @param titleColor the color of the title
+     */
+    @ConstructorProperties({"border", "title", "titleJustification", "titlePosition", "titleFont", "titleColor"})
+    public TitledBorder(Border border,
+                        String title,
+                        int titleJustification,
+                        int titlePosition,
+                        Font titleFont,
+                        Color titleColor)       {
+        this.title = title;
+        this.border = border;
+        this.titleFont = titleFont;
+        this.titleColor = titleColor;
+
+        setTitleJustification(titleJustification);
+        setTitlePosition(titlePosition);
+    }
+
+    /**
+     * Paints the border for the specified component with the
+     * specified position and size.
+     * @param c the component for which this border is being painted
+     * @param g the paint graphics
+     * @param x the x position of the painted border
+     * @param y the y position of the painted border
+     * @param width the width of the painted border
+     * @param height the height of the painted border
+     */
+    public void paintBorder(Component c, Graphics g, int x, int y, int width, int height) {
+
+        Border border = getBorder();
+
+        if (getTitle() == null || getTitle().equals("")) {
+            if (border != null) {
+                border.paintBorder(c, g, x, y, width, height);
+            }
+            return;
+        }
+
+        Rectangle grooveRect = new Rectangle(x + EDGE_SPACING, y + EDGE_SPACING,
+                                             width - (EDGE_SPACING * 2),
+                                             height - (EDGE_SPACING * 2));
+        Font font = g.getFont();
+        Color color = g.getColor();
+
+        g.setFont(getFont(c));
+
+        JComponent jc = (c instanceof JComponent) ? (JComponent)c : null;
+        FontMetrics fm = SwingUtilities2.getFontMetrics(jc, g);
+        int         fontHeight = fm.getHeight();
+        int         descent = fm.getDescent();
+        int         ascent = fm.getAscent();
+        int         diff;
+        int         stringWidth = SwingUtilities2.stringWidth(jc, fm,
+                                                              getTitle());
+        Insets      insets;
+
+        if (border != null) {
+            insets = border.getBorderInsets(c);
+        } else {
+            insets = new Insets(0, 0, 0, 0);
+        }
+
+        int titlePos = getTitlePosition();
+        switch (titlePos) {
+            case ABOVE_TOP:
+                diff = ascent + descent + (Math.max(EDGE_SPACING,
+                                 TEXT_SPACING*2) - EDGE_SPACING);
+                grooveRect.y += diff;
+                grooveRect.height -= diff;
+                textLoc.y = grooveRect.y - (descent + TEXT_SPACING);
+                break;
+            case TOP:
+            case DEFAULT_POSITION:
+                diff = Math.max(0, ((ascent/2) + TEXT_SPACING) - EDGE_SPACING);
+                grooveRect.y += diff;
+                grooveRect.height -= diff;
+                textLoc.y = (grooveRect.y - descent) +
+                (insets.top + ascent + descent)/2;
+                break;
+            case BELOW_TOP:
+                textLoc.y = grooveRect.y + insets.top + ascent + TEXT_SPACING;
+                break;
+            case ABOVE_BOTTOM:
+                textLoc.y = (grooveRect.y + grooveRect.height) -
+                (insets.bottom + descent + TEXT_SPACING);
+                break;
+            case BOTTOM:
+                grooveRect.height -= fontHeight/2;
+                textLoc.y = ((grooveRect.y + grooveRect.height) - descent) +
+                        ((ascent + descent) - insets.bottom)/2;
+                break;
+            case BELOW_BOTTOM:
+                grooveRect.height -= fontHeight;
+                textLoc.y = grooveRect.y + grooveRect.height + ascent +
+                        TEXT_SPACING;
+                break;
+        }
+
+        int justification = getTitleJustification();
+        if(isLeftToRight(c)) {
+            if(justification==LEADING ||
+               justification==DEFAULT_JUSTIFICATION) {
+                justification = LEFT;
+            }
+            else if(justification==TRAILING) {
+                justification = RIGHT;
+            }
+        }
+        else {
+            if(justification==LEADING ||
+               justification==DEFAULT_JUSTIFICATION) {
+                justification = RIGHT;
+            }
+            else if(justification==TRAILING) {
+                justification = LEFT;
+            }
+        }
+
+        switch (justification) {
+            case LEFT:
+                textLoc.x = grooveRect.x + TEXT_INSET_H + insets.left;
+                break;
+            case RIGHT:
+                textLoc.x = (grooveRect.x + grooveRect.width) -
+                        (stringWidth + TEXT_INSET_H + insets.right);
+                break;
+            case CENTER:
+                textLoc.x = grooveRect.x +
+                        ((grooveRect.width - stringWidth) / 2);
+                break;
+        }
+
+        // If title is positioned in middle of border AND its fontsize
+        // is greater than the border's thickness, we'll need to paint
+        // the border in sections to leave space for the component's background
+        // to show through the title.
+        //
+        if (border != null) {
+            if (((titlePos == TOP || titlePos == DEFAULT_POSITION) &&
+                  (grooveRect.y > textLoc.y - ascent)) ||
+                 (titlePos == BOTTOM &&
+                  (grooveRect.y + grooveRect.height < textLoc.y + descent))) {
+
+                Rectangle clipRect = new Rectangle();
+
+                // save original clip
+                Rectangle saveClip = g.getClipBounds();
+
+                // paint strip left of text
+                clipRect.setBounds(saveClip);
+                if (computeIntersection(clipRect, x, y, textLoc.x-1-x, height)) {
+                    g.setClip(clipRect);
+                    border.paintBorder(c, g, grooveRect.x, grooveRect.y,
+                                  grooveRect.width, grooveRect.height);
+                }
+
+                // paint strip right of text
+                clipRect.setBounds(saveClip);
+                if (computeIntersection(clipRect, textLoc.x+stringWidth+1, y,
+                               x+width-(textLoc.x+stringWidth+1), height)) {
+                    g.setClip(clipRect);
+                    border.paintBorder(c, g, grooveRect.x, grooveRect.y,
+                                  grooveRect.width, grooveRect.height);
+                }
+
+                if (titlePos == TOP || titlePos == DEFAULT_POSITION) {
+                    // paint strip below text
+                    clipRect.setBounds(saveClip);
+                    if (computeIntersection(clipRect, textLoc.x-1, textLoc.y+descent,
+                                        stringWidth+2, y+height-textLoc.y-descent)) {
+                        g.setClip(clipRect);
+                        border.paintBorder(c, g, grooveRect.x, grooveRect.y,
+                                  grooveRect.width, grooveRect.height);
+                    }
+
+                } else { // titlePos == BOTTOM
+                  // paint strip above text
+                    clipRect.setBounds(saveClip);
+                    if (computeIntersection(clipRect, textLoc.x-1, y,
+                          stringWidth+2, textLoc.y - ascent - y)) {
+                        g.setClip(clipRect);
+                        border.paintBorder(c, g, grooveRect.x, grooveRect.y,
+                                  grooveRect.width, grooveRect.height);
+                    }
+                }
+
+                // restore clip
+                g.setClip(saveClip);
+
+            } else {
+                border.paintBorder(c, g, grooveRect.x, grooveRect.y,
+                                  grooveRect.width, grooveRect.height);
+            }
+        }
+
+        g.setColor(getTitleColor());
+        SwingUtilities2.drawString(jc, g, getTitle(), textLoc.x, textLoc.y);
+
+        g.setFont(font);
+        g.setColor(color);
+    }
+
+    /**
+     * Reinitialize the insets parameter with this Border's current Insets.
+     * @param c the component for which this border insets value applies
+     * @param insets the object to be reinitialized
+     */
+    public Insets getBorderInsets(Component c, Insets insets) {
+        FontMetrics fm;
+        int         descent = 0;
+        int         ascent = 16;
+        int         height = 16;
+
+        Border border = getBorder();
+        if (border != null) {
+            if (border instanceof AbstractBorder) {
+                ((AbstractBorder)border).getBorderInsets(c, insets);
+            } else {
+                // Can't reuse border insets because the Border interface
+                // can't be enhanced.
+                Insets i = border.getBorderInsets(c);
+                insets.top = i.top;
+                insets.right = i.right;
+                insets.bottom = i.bottom;
+                insets.left = i.left;
+            }
+        } else {
+            insets.left = insets.top = insets.right = insets.bottom = 0;
+        }
+
+        insets.left += EDGE_SPACING + TEXT_SPACING;
+        insets.right += EDGE_SPACING + TEXT_SPACING;
+        insets.top += EDGE_SPACING + TEXT_SPACING;
+        insets.bottom += EDGE_SPACING + TEXT_SPACING;
+
+        if(c == null || getTitle() == null || getTitle().equals(""))    {
+            return insets;
+        }
+
+        Font font = getFont(c);
+
+        fm = c.getFontMetrics(font);
+
+        if(fm != null) {
+           descent = fm.getDescent();
+           ascent = fm.getAscent();
+           height = fm.getHeight();
+        }
+
+        switch (getTitlePosition()) {
+          case ABOVE_TOP:
+              insets.top += ascent + descent
+                            + (Math.max(EDGE_SPACING, TEXT_SPACING*2)
+                            - EDGE_SPACING);
+              break;
+          case TOP:
+          case DEFAULT_POSITION:
+              insets.top += ascent + descent;
+              break;
+          case BELOW_TOP:
+              insets.top += ascent + descent + TEXT_SPACING;
+              break;
+          case ABOVE_BOTTOM:
+              insets.bottom += ascent + descent + TEXT_SPACING;
+              break;
+          case BOTTOM:
+              insets.bottom += ascent + descent;
+              break;
+          case BELOW_BOTTOM:
+              insets.bottom += height;
+              break;
+        }
+        return insets;
+    }
+
+    /**
+     * Returns whether or not the border is opaque.
+     */
+    public boolean isBorderOpaque() { return false; }
+
+    /**
+     * Returns the title of the titled border.
+     */
+    public String getTitle()        {       return title;   }
+
+    /**
+     * Returns the border of the titled border.
+     */
+    public Border getBorder()       {
+        Border b = border;
+        if (b == null)
+            b = UIManager.getBorder("TitledBorder.border");
+        return b;
+    }
+
+    /**
+     * Returns the title-position of the titled border.
+     */
+    public int getTitlePosition()   {       return titlePosition;   }
+
+    /**
+     * Returns the title-justification of the titled border.
+     */
+    public int getTitleJustification()      {       return titleJustification;      }
+
+    /**
+     * Returns the title-font of the titled border.
+     */
+    public Font getTitleFont()      {
+        Font f = titleFont;
+        if (f == null)
+            f = UIManager.getFont("TitledBorder.font");
+        return f;
+    }
+
+    /**
+     * Returns the title-color of the titled border.
+     */
+    public Color getTitleColor()    {
+        Color c = titleColor;
+        if (c == null)
+            c = UIManager.getColor("TitledBorder.titleColor");
+        return c;
+    }
+
+
+    // REMIND(aim): remove all or some of these set methods?
+
+    /**
+     * Sets the title of the titled border.
+     * param title the title for the border
+     */
+    public void setTitle(String title)      {       this.title = title;     }
+
+    /**
+     * Sets the border of the titled border.
+     * @param border the border
+     */
+    public void setBorder(Border border)    {       this.border = border;   }
+
+    /**
+     * Sets the title-position of the titled border.
+     * @param titlePosition the position for the border
+     */
+    public void setTitlePosition(int titlePosition) {
+        switch (titlePosition) {
+          case ABOVE_TOP:
+          case TOP:
+          case BELOW_TOP:
+          case ABOVE_BOTTOM:
+          case BOTTOM:
+          case BELOW_BOTTOM:
+          case DEFAULT_POSITION:
+                this.titlePosition = titlePosition;
+                break;
+          default:
+            throw new IllegalArgumentException(titlePosition +
+                                        " is not a valid title position.");
+        }
+    }
+
+    /**
+     * Sets the title-justification of the titled border.
+     * @param titleJustification the justification for the border
+     */
+    public void setTitleJustification(int titleJustification)       {
+        switch (titleJustification) {
+          case DEFAULT_JUSTIFICATION:
+          case LEFT:
+          case CENTER:
+          case RIGHT:
+          case LEADING:
+          case TRAILING:
+            this.titleJustification = titleJustification;
+            break;
+          default:
+            throw new IllegalArgumentException(titleJustification +
+                                        " is not a valid title justification.");
+        }
+    }
+
+    /**
+     * Sets the title-font of the titled border.
+     * @param titleFont the font for the border title
+     */
+    public void setTitleFont(Font titleFont) {
+        this.titleFont = titleFont;
+    }
+
+    /**
+     * Sets the title-color of the titled border.
+     * @param titleColor the color for the border title
+     */
+    public void setTitleColor(Color titleColor) {
+      this.titleColor = titleColor;
+    }
+
+    /**
+     * Returns the minimum dimensions this border requires
+     * in order to fully display the border and title.
+     * @param c the component where this border will be drawn
+     */
+    public Dimension getMinimumSize(Component c) {
+        Insets insets = getBorderInsets(c);
+        Dimension minSize = new Dimension(insets.right+insets.left,
+                                          insets.top+insets.bottom);
+        Font font = getFont(c);
+        FontMetrics fm = c.getFontMetrics(font);
+        JComponent jc = (c instanceof JComponent) ? (JComponent)c : null;
+        switch (titlePosition) {
+          case ABOVE_TOP:
+          case BELOW_BOTTOM:
+              minSize.width = Math.max(SwingUtilities2.stringWidth(jc, fm,
+                                       getTitle()), minSize.width);
+              break;
+          case BELOW_TOP:
+          case ABOVE_BOTTOM:
+          case TOP:
+          case BOTTOM:
+          case DEFAULT_POSITION:
+          default:
+              minSize.width += SwingUtilities2.stringWidth(jc, fm, getTitle());
+        }
+        return minSize;
+    }
+
+    /**
+     * Returns the baseline.
+     *
+     * @throws NullPointerException {@inheritDoc}
+     * @throws IllegalArgumentException {@inheritDoc}
+     * @see javax.swing.JComponent#getBaseline(int, int)
+     * @since 1.6
+     */
+    public int getBaseline(Component c, int width, int height) {
+        if (c == null) {
+            throw new NullPointerException("Must supply non-null component");
+        }
+        if (height < 0) {
+            throw new IllegalArgumentException("Height must be >= 0");
+        }
+        String title = getTitle();
+        if (title != null && !"".equals(title)) {
+            Font font = getFont(c);
+            Border border2 = getBorder();
+            Insets borderInsets;
+            if (border2 != null) {
+                borderInsets = border2.getBorderInsets(c);
+            }
+            else {
+                borderInsets = new Insets(0, 0, 0, 0);
+            }
+            FontMetrics fm = c.getFontMetrics(font);
+            int fontHeight = fm.getHeight();
+            int descent = fm.getDescent();
+            int ascent = fm.getAscent();
+            int y = EDGE_SPACING;
+            int h = height - EDGE_SPACING * 2;
+            int diff;
+            switch (getTitlePosition()) {
+            case ABOVE_TOP:
+                diff = ascent + descent + (Math.max(EDGE_SPACING,
+                                                    TEXT_SPACING * 2) -
+                                           EDGE_SPACING);
+                return y + diff - (descent + TEXT_SPACING);
+            case TOP:
+            case DEFAULT_POSITION:
+                diff = Math.max(0, ((ascent/2) + TEXT_SPACING) -
+                                EDGE_SPACING);
+                return (y + diff - descent) +
+                    (borderInsets.top + ascent + descent)/2;
+            case BELOW_TOP:
+                return y + borderInsets.top + ascent + TEXT_SPACING;
+            case ABOVE_BOTTOM:
+                return (y + h) - (borderInsets.bottom + descent +
+                                  TEXT_SPACING);
+            case BOTTOM:
+                h -= fontHeight / 2;
+                return ((y + h) - descent) +
+                        ((ascent + descent) - borderInsets.bottom)/2;
+            case BELOW_BOTTOM:
+                h -= fontHeight;
+                return y + h + ascent + TEXT_SPACING;
+            }
+        }
+        return -1;
+    }
+
+    /**
+     * Returns an enum indicating how the baseline of the border
+     * changes as the size changes.
+     *
+     * @throws NullPointerException {@inheritDoc}
+     * @see javax.swing.JComponent#getBaseline(int, int)
+     * @since 1.6
+     */
+    public Component.BaselineResizeBehavior getBaselineResizeBehavior(
+            Component c) {
+        super.getBaselineResizeBehavior(c);
+        switch(getTitlePosition()) {
+        case TitledBorder.ABOVE_TOP:
+        case TitledBorder.TOP:
+        case TitledBorder.DEFAULT_POSITION:
+        case TitledBorder.BELOW_TOP:
+            return Component.BaselineResizeBehavior.CONSTANT_ASCENT;
+        case TitledBorder.ABOVE_BOTTOM:
+        case TitledBorder.BOTTOM:
+        case TitledBorder.BELOW_BOTTOM:
+            return JComponent.BaselineResizeBehavior.CONSTANT_DESCENT;
+        }
+        return Component.BaselineResizeBehavior.OTHER;
+    }
+
+    protected Font getFont(Component c) {
+        Font font;
+        if ((font = getTitleFont()) != null) {
+            return font;
+        } else if (c != null && (font = c.getFont()) != null) {
+            return font;
+        }
+        return new Font(Font.DIALOG, Font.PLAIN, 12);
+    }
+
+    private static boolean computeIntersection(Rectangle dest,
+                                               int rx, int ry, int rw, int rh) {
+        int x1 = Math.max(rx, dest.x);
+        int x2 = Math.min(rx + rw, dest.x + dest.width);
+        int y1 = Math.max(ry, dest.y);
+        int y2 = Math.min(ry + rh, dest.y + dest.height);
+        dest.x = x1;
+        dest.y = y1;
+        dest.width = x2 - x1;
+        dest.height = y2 - y1;
+
+        if (dest.width <= 0 || dest.height <= 0) {
+            return false;
+        }
+        return true;
+    }
+}