/*
* Copyright (C) 2014 Alfons Wirtz
* website www.freerouting.net
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 at <http://www.gnu.org/licenses/>
* for more details.
*
* PolylineShape.java
*
* Created on 16. November 2002, 09:34
*/
package geometry.planar;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedList;
/**
* Abstract class with functions for shapes, whose borders consist
* ob straight lines.
*
* @author Alfons Wirtz
*/
public abstract class PolylineShape implements Shape, java.io.Serializable
{
/**
* returns true, if the the shape has no infinite part at this corner
*/
public abstract boolean corner_is_bounded(int p_no);
/**
* Returns the number of border lines of the shape
*/
public abstract int border_line_count();
/**
* Returns the p_no-th corner of this shape for
* p_no between 0 and border_line_count() - 1.
* The corners are sorted starting with the smallest y-coordinate
* in counterclock sense arount the shape.
* If there are several corners with the smallest y-coordinate,
* the corner with the smallest x-coordinate comes first.
* Consecutive corners may be equal.
*/
public abstract Point corner(int p_no);
/**
* Turns this shape by p_factor times 90 degree around p_pole.
*/
public abstract PolylineShape turn_90_degree(int p_factor, IntPoint p_pole);
/**
* Rotates this shape around p_pole by p_angle.
* The result may be not exact.
*/
public abstract PolylineShape rotate_approx(double p_angle, FloatPoint p_pole);
/**
* Mirrors this shape at the horizontal line through p_pole.
*/
public abstract PolylineShape mirror_horizontal(IntPoint p_pole);
/**
* Mirrors this shape at the vertical line through p_pole.
*/
public abstract PolylineShape mirror_vertical(IntPoint p_pole);
/**
* Returns the affine translation of the area by p_vector
*/
public abstract PolylineShape translate_by(Vector p_vector);
/**
* Return all unbounded cornersw of this shape.
*/
public Point [] bounded_corners()
{
int corner_count = this.border_line_count();
Collection<Point> result_list = new LinkedList<Point>();
for (int i = 0; i < corner_count; ++i)
{
if (this.corner_is_bounded(i))
{
result_list.add(this.corner(i));
}
}
Point[] result = new Point[result_list.size()];
Iterator<Point> it = result_list.iterator();
for (int i = 0; i < result.length; ++i)
{
result[i] = it.next();
}
return result;
}
/**
* Returns an approximation of the p_no-th corner of this shape
* for p_no between 0 and border_line_count() - 1.
* If the shape is not bounded at this corner, the
* coordinates of the result will be set to Integer.MAX_VALUE.
*/
public FloatPoint corner_approx(int p_no)
{
return corner(p_no).to_float();
}
/**
* Returns an approximation of the all corners of this shape.
* If the shape is not bounded at a corner, the
* coordinates will be set to Integer.MAX_VALUE.
*/
public FloatPoint [] corner_approx_arr()
{
int corner_count = this.border_line_count();
FloatPoint [] result = new FloatPoint [corner_count];
for (int i = 0; i < corner_count; ++i)
{
result[i] = this.corner_approx(i);
}
return result;
}
/**
* If p_point is equal to a corner of this shape, the number
* of that corner is returned; -1 otherwise.
*/
public int equals_corner(Point p_point)
{
for (int i = 0; i < border_line_count(); ++i)
{
if (p_point.equals(corner(i)))
{
return i;
}
}
return -1;
}
/**
* Returns the cumulative border line length of the shape.
* If the shape is unbounded, Integer.MAX_VALUE is returned.
*/
public double circumference()
{
if (!is_bounded())
{
return Integer.MAX_VALUE;
}
int corner_count = border_line_count();
double result = 0;
FloatPoint prev_corner = corner_approx(corner_count - 1);
for (int i = 0; i < corner_count; ++i)
{
FloatPoint curr_corner = corner_approx(i);
result += curr_corner.distance(prev_corner);
prev_corner = curr_corner;
}
return result;
}
/**
* Returns the arithmetic middle of the corners of this shape
*/
public FloatPoint centre_of_gravity()
{
int corner_count = border_line_count();
double x = 0;
double y = 0;
for (int i = 0; i < corner_count; ++i)
{
FloatPoint curr_point = corner_approx(i);
x += curr_point.x;
y += curr_point.y;
}
x /= corner_count;
y /= corner_count;
return new FloatPoint(x, y);
}
/**
* checks, if this shape is completely contained in p_box.
*/
public boolean is_contained_in(IntBox p_box)
{
return p_box.contains(bounding_box());
}
/**
* Returns the index of the corner of the shape, so that all
* other points of the shape are to the right of the line
* from p_from_point to this corner
*/
public int index_of_left_most_corner(FloatPoint p_from_point)
{
FloatPoint left_most_corner = corner_approx(0);
int corner_count = border_line_count();
int result = 0;
for (int i = 1; i < corner_count; ++i)
{
FloatPoint curr_corner = corner_approx(i);
if (curr_corner.side_of(p_from_point, left_most_corner)== Side.ON_THE_LEFT)
{
left_most_corner = curr_corner;
result = i;
}
}
return result;
}
/**
* Returns the index of the corner of the shape, so that all
* other points of the shape are to the left of the line
* from p_from_point to this corner
*/
public int index_of_right_most_corner(FloatPoint p_from_point)
{
FloatPoint right_most_corner = corner_approx(0);
int corner_count = border_line_count();
int result = 0;
for (int i = 1; i < corner_count; ++i)
{
FloatPoint curr_corner = corner_approx(i);
if (curr_corner.side_of(p_from_point, right_most_corner) == Side.ON_THE_RIGHT)
{
right_most_corner = curr_corner;
result = i;
}
}
return result;
}
/**
* Returns a FloatLine result, so that result.a is an approximation of
* the left most corner of this shape when viewed from p_from_point,
* and result.b is an approximation of the right most corner.
*/
public FloatLine polar_line_segment(FloatPoint p_from_point)
{
if (this.is_empty())
{
System.out.println("PolylineShape.polar_line_segment: shape is empty");
return null;
}
FloatPoint left_most_corner = corner_approx(0);
FloatPoint right_most_corner = corner_approx(0);
int corner_count = border_line_count();
for (int i = 1; i < corner_count; ++i)
{
FloatPoint curr_corner = corner_approx(i);
if (curr_corner.side_of(p_from_point, right_most_corner) == Side.ON_THE_RIGHT)
{
right_most_corner = curr_corner;
}
if (curr_corner.side_of(p_from_point, left_most_corner)== Side.ON_THE_LEFT)
{
left_most_corner = curr_corner;
}
}
return new FloatLine(left_most_corner, right_most_corner);
}
/**
* Returns the p_no-th border line of this shape.
*/
public abstract Line border_line(int p_no);
/**
* Returns the previos border line or corner number of this shape.
*/
public int prev_no(int p_no)
{
int result;
if (p_no == 0)
{
result = border_line_count() - 1;
}
else
{
result = p_no - 1;
}
return result;
}
/**
* Returns the next border line or corner number of this shape.
*/
public int next_no(int p_no)
{
int result;
if (p_no == border_line_count() - 1)
{
result = 0;
}
else
{
result = p_no + 1;
}
return result;
}
public PolylineShape get_border()
{
return this;
}
public Shape[] get_holes()
{
return new Shape[0];
}
/**
* Checks, if this shape and p_line have a common point.
*/
public boolean intersects(Line p_line)
{
Side side_of_first_corner = p_line.side_of(corner(0));
if (side_of_first_corner == Side.COLLINEAR)
{
return true;
}
for (int i = 1; i < this.border_line_count(); ++i)
{
if (p_line.side_of(corner(i)) != side_of_first_corner)
{
return true;
}
}
return false;
}
/**
* Calculates the left most corner of this shape, when looked at from p_from_point.
*/
public Point left_most_corner(Point p_from_point)
{
if (this.is_empty())
{
return p_from_point;
}
Point result = this.corner(0);
int corner_count = this.border_line_count();
for (int i = 1; i < corner_count; ++i)
{
Point curr_corner = this.corner(i);
if (curr_corner.side_of(p_from_point, result) == Side.ON_THE_LEFT)
{
result = curr_corner;
}
}
return result;
}
/**
* Calculates the left most corner of this shape, when looked at from p_from_point.
*/
public Point right_most_corner(Point p_from_point)
{
if (this.is_empty())
{
return p_from_point;
}
Point result = this.corner(0);
int corner_count = this.border_line_count();
for (int i = 1; i < corner_count; ++i)
{
Point curr_corner = this.corner(i);
if (curr_corner.side_of(p_from_point, result) == Side.ON_THE_RIGHT)
{
result = curr_corner;
}
}
return result;
}
}