cubiccurve2d.java

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	}

	/**
	 * Returns the Y coordinate of the first control point 
	 * in double precision.
	 * @return the Y coordinate of the first control point of the
	 *		<code>CubicCurve2D</code>.
	 */
	public double getCtrlY1() {
	    return ctrly1;
	}

	/**
	 * Returns the first control point.
	 * @return a <code>Point2D</code> that is the first control point of the
	 *		<code>CubicCurve2D</code>.
	 */
	public Point2D getCtrlP1() {
	    return new Point2D.Double(ctrlx1, ctrly1);
	}

	/**
	 * Returns the X coordinate of the second control point
	 * in double precision.
	 * @return the X coordinate of the second control point of the
	 *		<code>CubicCurve2D</code>.
	 */
	public double getCtrlX2() {
	    return ctrlx2;
	}

	/**
	 * Returns the Y coordinate of the second control point
	 * in double precision.
	 * @return the Y coordinate of the second control point of the
	 *		<code>CubicCurve2D</code>.
	 */
	public double getCtrlY2() {
	    return ctrly2;
	}

	/**
	 * Returns the second control point.
	 * @return a <code>Point2D</code> that is the second control point of 
	 *		the <code>CubicCurve2D</code>.	
	 */
	public Point2D getCtrlP2() {
	    return new Point2D.Double(ctrlx2, ctrly2);
	}

	/**
	 * Returns the X coordinate of the end point
	 * in double precision.
	 * @return the X coordinate of the end point of the
	 *		<code>CubicCurve2D</code>.
	 */
	public double getX2() {
	    return x2;
	}

	/**
	 * Returns the Y coordinate of the end point 
	 * in double precision.
	 * @return the Y coordinate of the end point of the
	 *		<code>CubicCurve2D</code>.
	 */
	public double getY2() {
	    return y2;
	}

	/**
	 * Returns the end point.
	 * @return a <code>Point2D</code> that is the end point of 
	 *		the <code>CubicCurve2D</code>.	
	 */
	public Point2D getP2() {
	    return new Point2D.Double(x2, y2);
	}

	/**
	 * Sets the location of the endpoints and controlpoints
	 * of this curve to the specified double coordinates.
	 * @param x1,&nbsp;y1 the first specified coordinates used to set the start
	 *		point of this <code>CubicCurve2D</code>
	 * @param ctrlx1,&nbsp;ctrly1 the second specified coordinates used to set the
	 *		first control point of this <code>CubicCurve2D</code>
	 * @param ctrlx2,&nbsp;ctrly2 the third specified coordinates used to set the 
	 *		second control point of this <code>CubicCurve2D</code>		
	 * @param x2,&nbsp;y2 the fourth specified coordinates used to set the end
	 *		point of this <code>CubicCurve2D</code>	 
	 */
	public void setCurve(double x1, double y1,
			     double ctrlx1, double ctrly1,
			     double ctrlx2, double ctrly2,
			     double x2, double y2) {
	    this.x1     = x1;
	    this.y1     = y1;
	    this.ctrlx1 = ctrlx1;
	    this.ctrly1 = ctrly1;
	    this.ctrlx2 = ctrlx2;
	    this.ctrly2 = ctrly2;
	    this.x2     = x2;
	    this.y2     = y2;
	}

	/**
	 * Returns the bounding box of the shape.
	 * @return a <code>Rectangle2D</code> that is the bounding box
	 *		of the shape.
	 */
	public Rectangle2D getBounds2D() {
	    double left   = Math.min(Math.min(x1, x2),
				     Math.min(ctrlx1, ctrlx2));
	    double top    = Math.min(Math.min(y1, y2),
				     Math.min(ctrly1, ctrly2));
	    double right  = Math.max(Math.max(x1, x2),
				     Math.max(ctrlx1, ctrlx2));
	    double bottom = Math.max(Math.max(y1, y2),
				     Math.max(ctrly1, ctrly2));
	    return new Rectangle2D.Double(left, top,
					  right - left, bottom - top);
	}
    }

    /**
     * This is an abstract class that cannot be instantiated directly.
     * Type-specific implementation subclasses are available for
     * instantiation and provide a number of formats for storing
     * the information necessary to satisfy the various accessor
     * methods below.
     *
     * @see java.awt.geom.CubicCurve2D.Float
     * @see java.awt.geom.CubicCurve2D.Double
     */
    protected CubicCurve2D() {
    }

    /**
     * Returns the X coordinate of the start point in double precision.
     * @return the X coordinate of the start point of the
     *		<code>CubicCurve2D</code>.
     */
    public abstract double getX1();

    /**
     * Returns the Y coordinate of the start point in double precision.
     * @return the Y coordinate of the start point of the
     *		<code>CubicCurve2D</code>.
     */
    public abstract double getY1();

    /**
     * Returns the start point.
     * @return a <code>Point2D</code> that is the start point of 
     *		the <code>CubicCurve2D</code>.
     */
    public abstract Point2D getP1();

    /**
     * Returns the X coordinate of the first control point in double precision.
     * @return the X coordinate of the first control point of the
     *		<code>CubicCurve2D</code>.
     */
    public abstract double getCtrlX1();

    /**
     * Returns the Y coordinate of the first control point in double precision.
     * @return the Y coordinate of the first control point of the
     *		<code>CubicCurve2D</code>.
     */
    public abstract double getCtrlY1();

    /**
     * Returns the first control point.
     * @return a <code>Point2D</code> that is the first control point of 
     *		the <code>CubicCurve2D</code>.
     */
    public abstract Point2D getCtrlP1();

    /**
     * Returns the X coordinate of the second control point
     * in double precision.
     * @return the X coordinate of the second control point of the
     *		<code>CubicCurve2D</code>.
     */
    public abstract double getCtrlX2();

    /**
     * Returns the Y coordinate of the second control point
     * in double precision.
     * @return the Y coordinate of the second control point of the
     *		<code>CubicCurve2D</code>.
     */
    public abstract double getCtrlY2();

    /**
     * Returns the second control point.
     * @return a <code>Point2D</code> that is the second control point of 
     *		the <code>CubicCurve2D</code>.
     */
    public abstract Point2D getCtrlP2();

    /**
     * Returns the X coordinate of the end point in double precision.
     * @return the X coordinate of the end point of the
     *		<code>CubicCurve2D</code>.
     */
    public abstract double getX2();

    /**
     * Returns the Y coordinate of the end point in double precision.
     * @return the Y coordinate of the end point of the
     *		<code>CubicCurve2D</code>.
     */
    public abstract double getY2();

    /**
     * Returns the end point.
     * @return a <code>Point2D</code> that is the end point of 
     *		the <code>CubicCurve2D</code>.
     */
    public abstract Point2D getP2();

    /**
     * Sets the location of the endpoints and controlpoints of this curve
     * to the specified double coordinates.
     * @param x1,&nbsp;y1 the first specified coordinates used to set the start
     *		point of this <code>CubicCurve2D</code>
     * @param ctrlx1,&nbsp;ctrly1 the second specified coordinates used to set the
     *		first control point of this <code>CubicCurve2D</code>
     * @param ctrlx2,&nbsp;ctrly2 the third specified coordinates used to set the 
     *		second control point of this <code>CubicCurve2D</code>		
     * @param x2,&nbsp;y2 the fourth specified coordinates used to set the end
     *		point of this <code>CubicCurve2D</code>	 
     */
    public abstract void setCurve(double x1, double y1,
				  double ctrlx1, double ctrly1,
				  double ctrlx2, double ctrly2,
				  double x2, double y2);

    /**
     * Sets the location of the endpoints and controlpoints of this curve
     * to the double coordinates at the specified offset in the specified
     * array.
     * @param coords a double array containing coordinates
     * @param offset the index of <code>coords</code> at which to begin 
     *		setting the endpoints and controlpoints of this curve
     *		to the coordinates contained in <code>coords</code>	
     */
    public void setCurve(double[] coords, int offset) {
	setCurve(coords[offset + 0], coords[offset + 1],
		 coords[offset + 2], coords[offset + 3],
		 coords[offset + 4], coords[offset + 5],
		 coords[offset + 6], coords[offset + 7]);
    }

    /**
     * Sets the location of the endpoints and controlpoints of this curve
     * to the specified <code>Point2D</code> coordinates.
     * @param p1 the first specified <code>Point2D</code> used to set the
     *		start point of this curve
     * @param cp1 the second specified <code>Point2D</code> used to set the
     *		first control point of this curve
     * @param cp2 the third specified <code>Point2D</code> used to set the
     *		second control point of this curve
     * @param p2 the fourth specified <code>Point2D</code> used to set the
     *		end point of this curve
     */
    public void setCurve(Point2D p1, Point2D cp1, Point2D cp2, Point2D p2) {
	setCurve(p1.getX(), p1.getY(), cp1.getX(), cp1.getY(),
		 cp2.getX(), cp2.getY(), p2.getX(), p2.getY());
    }

    /**
     * Sets the location of the endpoints and controlpoints of this curve
     * to the coordinates of the <code>Point2D</code> objects at the specified 
     * offset in the specified array.
     * @param pts an array of <code>Point2D</code> objects
     * @param offset  the index of <code>pts</code> at which to begin setting
     *		the endpoints and controlpoints of this curve to the 
     *		points contained in <code>pts</code>
     */
    public void setCurve(Point2D[] pts, int offset) {
	setCurve(pts[offset + 0].getX(), pts[offset + 0].getY(),
		 pts[offset + 1].getX(), pts[offset + 1].getY(),
		 pts[offset + 2].getX(), pts[offset + 2].getY(),
		 pts[offset + 3].getX(), pts[offset + 3].getY());
    }

    /**
     * Sets the location of the endpoints and controlpoints of this curve
     * to the same as those in the specified <code>CubicCurve2D</code>.
     * @param c the specified <code>CubicCurve2D</code>
     */
    public void setCurve(CubicCurve2D c) {
	setCurve(c.getX1(), c.getY1(), c.getCtrlX1(), c.getCtrlY1(),
		 c.getCtrlX2(), c.getCtrlY2(), c.getX2(), c.getY2());
    }

    /**
     * Returns the square of the flatness of the cubic curve specified
     * by the indicated controlpoints. The flatness is the maximum distance 
     * of a controlpoint from the line connecting the endpoints.
     * @param x1,&nbsp;y1 the first specified coordinates that specify the start
     *		point of a <code>CubicCurve2D</code>
     * @param ctrlx1,&nbsp;ctrly1 the second specified coordinates that specify the 
     * 		first control point of a <code>CubicCurve2D</code>
     * @param ctrlx2,&nbsp;ctrly2 the third specified coordinates that specify the 
     * 		second control point of a <code>CubicCurve2D</code>	
     * @param x2,&nbsp;y2 the fourth specified coordinates that specify the 
     * 		end point of a <code>CubicCurve2D</code>
     * @return the square of the flatness of the <code>CubicCurve2D</code>
     *		represented by the specified coordinates.
     */
    public static double getFlatnessSq(double x1, double y1,
				       double ctrlx1, double ctrly1,
				       double ctrlx2, double ctrly2,
				       double x2, double y2) {
	return Math.max(Line2D.ptSegDistSq(x1, y1, x2, y2, ctrlx1, ctrly1),
			Line2D.ptSegDistSq(x1, y1, x2, y2, ctrlx2, ctrly2));
			
    }

    /**
     * Returns the flatness of the cubic curve specified
     * by the indicated controlpoints. The flatness is the maximum distance 
     * of a controlpoint from the line connecting the endpoints.
     * @param x1,&nbsp;y1 the first specified coordinates that specify the start
     *		point of a <code>CubicCurve2D</code>
     * @param ctrlx1,&nbsp;ctrly1 the second specified coordinates that specify the 
     * 		first control point of a <code>CubicCurve2D</code>
     * @param ctrlx2,&nbsp;ctrly2 the third specified coordinates that specify the 
     * 		second control point of a <code>CubicCurve2D</code>	
     * @param x2,&nbsp;y2 the fourth specified coordinates that specify the 
     * 		end point of a <code>CubicCurve2D</code>
     * @return the flatness of the <code>CubicCurve2D</code>
     *		represented by the specified coordinates.
     */
    public static double getFlatness(double x1, double y1,
				     double ctrlx1, double ctrly1,
				     double ctrlx2, double ctrly2,
				     double x2, double y2) {
	return Math.sqrt(getFlatnessSq(x1, y1, ctrlx1, ctrly1,
				       ctrlx2, ctrly2, x2, y2));
    }

    /**
     * Returns the square of the flatness of the cubic curve specified
     * by the controlpoints stored in the indicated array at the 
     * indicated index. The flatness is the maximum distance 
     * of a controlpoint from the line connecting the endpoints.
     * @param coords an array containing coordinates
     * @param offset the index of <code>coords</code> at which to begin 
     *		setting the endpoints and controlpoints of this curve
     *		to the coordinates contained in <code>coords</code>
     * @return the square of the flatness of the <code>CubicCurve2D</code>
     *		specified by the coordinates in <code>coords</code> at
     *		the specified offset.
     */
    public static double getFlatnessSq(double coords[], int offset) {
	return getFlatnessSq(coords[offset + 0], coords[offset + 1],
			     coords[offset + 2], coords[offset + 3],
			     coords[offset + 4], coords[offset + 5],
			     coords[offset + 6], coords[offset + 7]);
    }

    /**
     * Returns the flatness of the cubic curve specified
     * by the controlpoints stored in the indicated array at the 
     * indicated index.  The flatness is the maximum distance 
     * of a controlpoint from the line connecting the endpoints.
     * @param coords an array containing coordinates
     * @param offset the index of <code>coords</code> at which to begin 
     *		setting the endpoints and controlpoints of this curve
     *		to the coordinates contained in <code>coords</code>
     * @return the flatness of the <code>CubicCurve2D</code>
     *		specified by the coordinates in <code>coords</code> at
     *		the specified offset.
     */
    public static double getFlatness(double coords[], int offset) {
	return getFlatness(coords[offset + 0], coords[offset + 1],
			   coords[offset + 2], coords[offset + 3],
			   coords[offset + 4], coords[offset + 5],
			   coords[offset + 6], coords[offset + 7]);
    }

    /**
     * Returns the square of the flatness of this curve.  The flatness is the 
     * maximum distance of a controlpoint from the line connecting the 
     * endpoints.
     * @return the square of the flatness of this curve.
     */
    public double getFlatnessSq() {
	return getFlatnessSq(getX1(), getY1(), getCtrlX1(), getCtrlY1(),
			     getCtrlX2(), getCtrlY2(), getX2(), getY2());
    }

    /**
     * Returns the flatness of this curve.  The flatness is the 
     * maximum distance of a controlpoint from the line connecting the 
     * endpoints.
     * @return the flatness of this curve.
     */
    public double getFlatness() {
	return getFlatness(getX1(), getY1(), getCtrlX1(), getCtrlY1(),
			   getCtrlX2(), getCtrlY2(), getX2(), getY2());
    }

    /**
     * Subdivides this cubic curve and stores the resulting two
     * subdivided curves into the left and right curve parameters.