rectangle2d.java

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  }

  /**
   * Return the hashcode for this rectangle. The formula is not documented, but
   * appears to be the same as:
   * <pre>
   * long l = Double.doubleToLongBits(getX())
   *   + 37 * Double.doubleToLongBits(getY())
   *   + 43 * Double.doubleToLongBits(getWidth())
   *   + 47 * Double.doubleToLongBits(getHeight());
   * return (int) ((l >> 32) ^ l);
   * </pre>
   *
   * @return the hashcode
   */
  public int hashCode()
  {
    // Talk about a fun time reverse engineering this one!
    long l = java.lang.Double.doubleToLongBits(getX())
      + 37 * java.lang.Double.doubleToLongBits(getY())
      + 43 * java.lang.Double.doubleToLongBits(getWidth())
      + 47 * java.lang.Double.doubleToLongBits(getHeight());
    return (int) ((l >> 32) ^ l);
  }

  /**
   * Tests this rectangle for equality against the specified object.  This
   * will be true if an only if the specified object is an instance of
   * Rectangle2D with the same coordinates and dimensions.
   *
   * @param obj the object to test against for equality
   * @return true if the specified object is equal to this one
   */
  public boolean equals(Object obj)
  {
    if (! (obj instanceof Rectangle2D))
      return false;
    Rectangle2D r = (Rectangle2D) obj;
    return r.getX() == getX() && r.getY() == getY()
      && r.getWidth() == getWidth() && r.getHeight() == getHeight();
  }

  /**
   * This class defines a rectangle in <code>double</code> precision.
   *
   * @author Eric Blake <[e-mail]>
   * @since 1.2
   * @status updated to 1.4
   */
  public static class Double extends Rectangle2D
  {
    /** The x coordinate of the lower left corner. */
    public double x;

    /** The y coordinate of the lower left corner. */
    public double y;

    /** The width of the rectangle. */
    public double width;

    /** The height of the rectangle. */
    public double height;

    /**
     * Create a rectangle at (0,0) with width 0 and height 0.
     */
    public Double()
    {
    }

    /**
     * Create a rectangle with the given values.
     *
     * @param x the x coordinate
     * @param y the y coordinate
     * @param w the width
     * @param h the height
     */
    public Double(double x, double y, double w, double h)
    {
      this.x = x;
      this.y = y;
      width = w;
      height = h;
    }

    /**
     * Return the X coordinate.
     *
     * @return the value of x
     */
    public double getX()
    {
      return x;
    }

    /**
     * Return the Y coordinate.
     *
     * @return the value of y
     */
    public double getY()
    {
      return y;
    }

    /**
     * Return the width.
     *
     * @return the value of width
     */
    public double getWidth()
    {
      return width;
    }

    /**
     * Return the height.
     *
     * @return the value of height
     */
    public double getHeight()
    {
      return height;
    }

    /**
     * Test if the rectangle is empty.
     *
     * @return true if width or height is not positive
     */
    public boolean isEmpty()
    {
      return width <= 0 || height <= 0;
    }

    /**
     * Set the contents of this rectangle to those specified.
     *
     * @param x the x coordinate
     * @param y the y coordinate
     * @param w the width
     * @param h the height
     */
    public void setRect(double x, double y, double w, double h)
    {
      this.x = x;
      this.y = y;
      width = w;
      height = h;
    }

    /**
     * Set the contents of this rectangle to those specified.
     *
     * @param r the rectangle to copy
     * @throws NullPointerException if r is null
     */
    public void setRect(Rectangle2D r)
    {
      x = r.getX();
      y = r.getY();
      width = r.getWidth();
      height = r.getHeight();
    }

    /**
     * Determine where the point lies with respect to this rectangle. The
     * result will be the binary OR of the appropriate bit masks.
     *
     * @param x the x coordinate to check
     * @param y the y coordinate to check
     * @return the binary OR of the result
     * @see #OUT_LEFT
     * @see #OUT_TOP
     * @see #OUT_RIGHT
     * @see #OUT_BOTTOM
     * @since 1.2
     */
    public int outcode(double x, double y)
    {
      int result = 0;
      if (width <= 0)
        result |= OUT_LEFT | OUT_RIGHT;
      else if (x < this.x)
        result |= OUT_LEFT;
      else if (x > this.x + width)
        result |= OUT_RIGHT;
      if (height <= 0)
        result |= OUT_BOTTOM | OUT_TOP;
      else if (y < this.y) // Remember that +y heads top-to-bottom.
        result |= OUT_TOP;
      else if (y > this.y + height)
        result |= OUT_BOTTOM;
      return result;
    }

    /**
     * Returns the bounds of this rectangle. A pretty useless method, as this
     * is already a rectangle.
     *
     * @return a copy of this rectangle
     */
    public Rectangle2D getBounds2D()
    {
      return new Double(x, y, width, height);
    }

    /**
     * Return a new rectangle which is the intersection of this and the given
     * one. The result will be empty if there is no intersection.
     *
     * @param r the rectangle to be intersected
     * @return the intersection
     * @throws NullPointerException if r is null
     */
    public Rectangle2D createIntersection(Rectangle2D r)
    {
      Double res = new Double();
      intersect(this, r, res);
      return res;
    }

    /**
     * Return a new rectangle which is the union of this and the given one.
     *
     * @param r the rectangle to be merged
     * @return the union
     * @throws NullPointerException if r is null
     */
    public Rectangle2D createUnion(Rectangle2D r)
    {
      Double res = new Double();
      union(this, r, res);
      return res;
    }

    /**
     * Returns a string representation of this rectangle. This is in the form
     * <code>getClass().getName() + "[x=" + x + ",y=" + y + ",w=" + width
     * + ",h=" + height + ']'</code>.
     *
     * @return a string representation of this rectangle
     */
    public String toString()
    {
      return getClass().getName() + "[x=" + x + ",y=" + y + ",w=" + width
        + ",h=" + height + ']';
    }
  } // class Double

  /**
   * This class defines a rectangle in <code>float</code> precision.
   *
   * @author Eric Blake <[e-mail]>
   * @since 1.2
   * @status updated to 1.4
   */
  public static class Float extends Rectangle2D
  {
    /** The x coordinate of the lower left corner. */
    public float x;

    /** The y coordinate of the lower left corner. */
    public float y;

    /** The width of the rectangle. */
    public float width;

    /** The height of the rectangle. */
    public float height;

    /**
     * Create a rectangle at (0,0) with width 0 and height 0.
     */
    public Float()
    {
    }

    /**
     * Create a rectangle with the given values.
     *
     * @param x the x coordinate
     * @param y the y coordinate
     * @param w the width
     * @param h the height
     */
    public Float(float x, float y, float w, float h)
    {
      this.x = x;
      this.y = y;
      width = w;
      height = h;
    }

    /**
     * Create a rectangle with the given values.
     *
     * @param x the x coordinate
     * @param y the y coordinate
     * @param w the width
     * @param h the height
     */
    Float(double x, double y, double w, double h)
    {
      this.x = (float) x;
      this.y = (float) y;
      width = (float) w;
      height = (float) h;
    }

    /**
     * Return the X coordinate.
     *
     * @return the value of x
     */
    public double getX()
    {
      return x;
    }

    /**
     * Return the Y coordinate.
     *
     * @return the value of y
     */
    public double getY()
    {
      return y;
    }

    /**
     * Return the width.
     *
     * @return the value of width
     */
    public double getWidth()
    {
      return width;
    }

    /**
     * Return the height.
     *
     * @return the value of height
     */
    public double getHeight()
    {
      return height;
    }

    /**
     * Test if the rectangle is empty.
     *
     * @return true if width or height is not positive
     */
    public boolean isEmpty()
    {
      return width <= 0 || height <= 0;
    }

    /**
     * Set the contents of this rectangle to those specified.
     *
     * @param x the x coordinate
     * @param y the y coordinate
     * @param w the width
     * @param h the height
     */
    public void setRect(float x, float y, float w, float h)
    {
      this.x = x;
      this.y = y;
      width = w;
      height = h;
    }

    /**
     * Set the contents of this rectangle to those specified.
     *
     * @param x the x coordinate
     * @param y the y coordinate
     * @param w the width
     * @param h the height
     */
    public void setRect(double x, double y, double w, double h)
    {
      this.x = (float) x;
      this.y = (float) y;
      width = (float) w;
      height = (float) h;
    }

    /**
     * Set the contents of this rectangle to those specified.
     *
     * @param r the rectangle to copy
     * @throws NullPointerException if r is null
     */
    public void setRect(Rectangle2D r)
    {
      x = (float) r.getX();
      y = (float) r.getY();
      width = (float) r.getWidth();
      height = (float) r.getHeight();
    }

    /**
     * Determine where the point lies with respect to this rectangle. The
     * result will be the binary OR of the appropriate bit masks.
     *
     * @param x the x coordinate to check
     * @param y the y coordinate to check
     * @return the binary OR of the result
     * @see #OUT_LEFT
     * @see #OUT_TOP
     * @see #OUT_RIGHT
     * @see #OUT_BOTTOM
     * @since 1.2
     */
    public int outcode(double x, double y)
    {
      int result = 0;
      if (width <= 0)
        result |= OUT_LEFT | OUT_RIGHT;
      else if (x < this.x)
        result |= OUT_LEFT;
      else if (x > this.x + width)
        result |= OUT_RIGHT;
      if (height <= 0)
        result |= OUT_BOTTOM | OUT_TOP;
      else if (y < this.y) // Remember that +y heads top-to-bottom.
        result |= OUT_TOP;
      else if (y > this.y + height)
        result |= OUT_BOTTOM;
      return result;
    }

    /**
     * Returns the bounds of this rectangle. A pretty useless method, as this
     * is already a rectangle.
     *
     * @return a copy of this rectangle
     */
    public Rectangle2D getBounds2D()
    {
      return new Float(x, y, width, height);
    }

    /**
     * Return a new rectangle which is the intersection of this and the given
     * one. The result will be empty if there is no intersection.
     *
     * @param r the rectangle to be intersected
     * @return the intersection
     * @throws NullPointerException if r is null
     */
    public Rectangle2D createIntersection(Rectangle2D r)
    {
      Float res = new Float();
      intersect(this, r, res);
      return res;
    }

    /**
     * Return a new rectangle which is the union of this and the given one.
     *
     * @param r the rectangle to be merged
     * @return the union
     * @throws NullPointerException if r is null
     */
    public Rectangle2D createUnion(Rectangle2D r)
    {
      Float res = new Float();
      union(this, r, res);
      return res;
    }

    /**
     * Returns a string representation of this rectangle. This is in the form
     * <code>getClass().getName() + "[x=" + x + ",y=" + y + ",w=" + width
     * + ",h=" + height + ']'</code>.
     *
     * @return a string representation of this rectangle
     */
    public String toString()
    {
      return getClass().getName() + "[x=" + x + ",y=" + y + ",w=" + width
        + ",h=" + height + ']';
    }
  } // class Float
} // class Rectangle2D