gcc/libjava/java/awt/geom/RoundRectangle2D.java

/* Copyright (C) 2000, 2002  Free Software Foundation

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package java.awt.geom;

/** This class implements a rectangle with rounded corners.
 * @author Tom Tromey <tromey@cygnus.com>
 * @date December 3, 2000
 */
public abstract class RoundRectangle2D extends RectangularShape
{
  /** Return the arc height of this round rectangle.  */
  public abstract double getArcHeight ();

  /** Return the arc width of this round rectangle.  */
  public abstract double getArcWidth ();

  /** Set the values of this round rectangle
   * @param x The x coordinate
   * @param y The y coordinate
   * @param w The width
   * @param h The height
   * @param arcWidth The arc width
   * @param arcHeight The arc height
   */
  public abstract void setRoundRect (double x, double y, double w, double h,
				     double arcWidth, double arcHeight);

  /** Create a RoundRectangle2D.  This is protected because this class
   * is abstract and cannot be instantiated.
   */
  protected  RoundRectangle2D ()
  {
  }

  /** Return true if this object contains the specified point.
   * @param x The x coordinate
   * @param y The y coordinate
   */
  public boolean contains (double x, double y)
  {
    double mx = getX ();
    double mw = getWidth ();
    if (x < mx || x >= mx + mw)
      return false;
    double my = getY ();
    double mh = getHeight ();
    if (y < my || y >= my + mh)
      return false;

    // Now check to see if the point is in range of an arc.
    double dy = Math.min (Math.abs (my - y), Math.abs (my + mh - y));
    double dx = Math.min (Math.abs (mx - x), Math.abs (mx + mw - x));
    double aw = getArcWidth ();
    double ah = getArcHeight ();
    if (dx > aw || dy > ah)
      return true;

    // At this point DX represents the distance from the nearest edge
    // of the rectangle.  But we want to transform it to represent the
    // scaled distance from the center of the ellipse that forms the
    // arc.  Hence this code:
    dy = (ah - dy) / ah;
    dx = (aw - dx) / aw;

    return dx * dx + dy * dy <= 1.0;
  }

  /** Return true if this object contains the specified rectangle
   * @param x The x coordinate
   * @param y The y coordinate
   * @param w The width
   * @param h The height
   */
  public boolean contains (double x, double y, double w, double h)
  {
    // We have to check all four points here (for ordinary rectangles
    // we can just check opposing corners).
    return (contains (x, y) && contains (x + w, h)
	    && contains (x, y + h) && contains (x + w, y + h));
  }

  /** Return a new path iterator which iterates over this rectangle.
   * @param at An affine transform to apply to the object
   */
  public PathIterator getPathIterator (AffineTransform at)
  {
    // FIXME.
    return null;
  }

  /** Return true if the given rectangle intersects this shape.
   * @param x The x coordinate
   * @param y The y coordinate
   * @param w The width
   * @param h The height
   */
  public boolean intersects (double x, double y, double w, double h)
  {
    // Here we can use the same code we use for an ordinary rectangle.
    double mx = getX ();
    double mw = getWidth ();
    if (x < mx || x >= mx + mw || x + w < mx || x + w >= mx + mw)
      return false;
    double my = getY ();
    double mh = getHeight ();
    return y >= my && y < my + mh && y + h >= my && y + h < my + mh;
  }

  /** Set the boundary of this round rectangle.
   * @param x The x coordinate
   * @param y The y coordinate
   * @param w The width
   * @param h The height
   */
  public void setFrame (double x, double y, double w, double h)
  {
    // This is a bit lame.
    setRoundRect (x, y, w, h, getArcWidth (), getArcHeight ());
  }

  /** Set the values of this round rectangle to be the same as those
   * of the argument.
   * @param rr The round rectangle to copy
   */
  public void setRoundRect (RoundRectangle2D rr)
  {
    setRoundRect (rr.getX (), rr.getY (), rr.getWidth (), rr.getHeight (),
		  rr.getArcWidth (), rr.getArcHeight ());
  }

  /** A subclass of RoundRectangle which keeps its parameters as
   * floats.  */
  public static class Float extends RoundRectangle2D
  {
    /** The height of the corner arc.  */
    public float archeight;

    /** The width of the corner arc.  */
    public float arcwidth;

    /** The x coordinate of this object.  */
    public float x;

    /** The y coordinate of this object.  */
    public float y;

    /** The width of this object.  */
    public float width;

    /** The height of this object.  */
    public float height;

    /** Construct a new instance, with all parameters set to 0.  */
    public Float ()
    {
      this (0, 0, 0, 0, 0, 0);
    }

    /** Construct a new instance with the given arguments.
     * @param x The x coordinate
     * @param y The y coordinate
     * @param w The width
     * @param h The height
     * @param arcWidth The arc width
     * @param arcHeight The arc height
     */
    public Float (float x, float y, float w, float h,
		  float arcWidth, float arcHeight)
    {
      this.x = x;
      this.y = y;
      this.width = w;
      this.height = h;
      this.arcwidth = arcWidth;
      this.archeight = arcHeight;
    }

    public double getArcHeight ()
    {
      return archeight;
    }

    public double getArcWidth ()
    {
      return arcwidth;
    }

    public Rectangle2D getBounds2D ()
    {
      return new Rectangle2D.Float (x, y, width, height);
    }

    public double getX ()
    {
      return x;
    }

    public double getY ()
    {
      return y;
    }

    public double getWidth ()
    {
      return width;
    }

    public double getHeight ()
    {
      return height;
    }

    public boolean isEmpty ()
    {
      return width <= 0 || height <= 0;
    }

    public void setRoundRect (float x, float y, float w, float h,
			      float arcWidth, float arcHeight)
    {
      this.x = x;
      this.y = y;
      this.width = w;
      this.height = h;
      this.arcwidth = arcWidth;
      this.archeight = arcHeight;
    }

    public void setRoundRect (double x, double y, double w, double h,
			      double arcWidth, double arcHeight)
    {
      this.x = (float) x;
      this.y = (float) y;
      this.width = (float) w;
      this.height = (float) h;
      this.arcwidth = (float) arcWidth;
      this.archeight = (float) arcHeight;
    }
  }

  /** A subclass of RoundRectangle which keeps its parameters as
   * doubles.  */
  public static class Double extends RoundRectangle2D
  {
    /** The height of the corner arc.  */
    public double archeight;

    /** The width of the corner arc.  */
    public double arcwidth;

    /** The x coordinate of this object.  */
    public double x;

    /** The y coordinate of this object.  */
    public double y;

    /** The width of this object.  */
    public double width;

    /** The height of this object.  */
    public double height;

    /** Construct a new instance, with all parameters set to 0.  */
    public Double ()
    {
      this (0, 0, 0, 0, 0, 0);
    }

    /** Construct a new instance with the given arguments.
     * @param x The x coordinate
     * @param y The y coordinate
     * @param w The width
     * @param h The height
     * @param arcWidth The arc width
     * @param arcHeight The arc height
     */
    public Double (double x, double y, double w, double h,
		   double arcWidth, double arcHeight)
    {
      this.x = x;
      this.y = y;
      this.width = w;
      this.height = h;
      this.arcwidth = arcWidth;
      this.archeight = arcHeight;
    }

    public double getArcHeight ()
    {
      return archeight;
    }

    public double getArcWidth ()
    {
      return arcwidth;
    }

    public Rectangle2D getBounds2D ()
    {
      return new Rectangle2D.Double (x, y, width, height);
    }

    public double getX ()
    {
      return x;
    }

    public double getY ()
    {
      return y;
    }

    public double getWidth ()
    {
      return width;
    }

    public double getHeight ()
    {
      return height;
    }

    public boolean isEmpty ()
    {
      return width <= 0 || height <= 0;
    }

    public void setRoundRect (double x, double y, double w, double h,
			      double arcWidth, double arcHeight)
    {
      this.x = x;
      this.y = y;
      this.width = w;
      this.height = h;
      this.arcwidth = arcWidth;
      this.archeight = arcHeight;
    }
  }
}