#include "boundary.h"

boundary::boundary()
{
	note=40; //middle C
}

boundary::boundary(int _note)
{
	note=_note;
}

boundary::~boundary()
{
}


void boundary::draw(){
	if (points.size()>1) {
		for (int i=0;i<points.size();i++) {
			ofLine(points[i],points[(i+1)%points.size()]);
		}
		ofDrawBitmapString(ofToString(note),centroid);
	}
}

void boundary::add(ofPoint p){
	points.push_back(p);
	getCentroid();
}
void boundary::undo(){
	if (points.size()>0) {
		points.erase(points.end()-1);
		getCentroid();
	}
}

void boundary::getCentroid(){
	float x=0;
	float y=0;
	for (int i=0;i<points.size();i++) {
		x+=points[i].x;
		y+=points[i].y;
	}
	centroid=ofPoint(x/points.size(),y/points.size(),0);
}

bool boundary::contains(ofPoint p)
//winding rule algorithm for 2D polygon containment test
//thanks to Paul Bourke
//http://local.wasp.uwa.edu.au/~pbourke/geometry/insidepoly/
{
  int counter = 0;
  int i;
  double xinters;
  ofPoint p1,p2;

  p1 = points[0];
  for (i=1;i<=points.size();i++) {
    p2 = points[i % points.size()];
    if (p.y > min(p1.y,p2.y)) {
      if (p.y <= max(p1.y,p2.y)) {
        if (p.x <= max(p1.x,p2.x)) {
          if (p1.y != p2.y) {
            xinters = (p.y-p1.y)*(p2.x-p1.x)/(p2.y-p1.y)+p1.x;
            if (p1.x == p2.x || p.x <= xinters)
              counter++;
          }
        }
      }
    }
    p1 = p2;
  }

  if (counter % 2 == 0)
    return false;
  else
    return true;
}