#include <halfspaceD2draw.h>

void halfspaceD2draw::draw() 
{
  glColor3ub(0,255,0);
  glBegin(GL_LINES);
  glVertex3f(h.p0.x,h.p0.y,0.0);
  glColor3ub(255,0,0);
  glVertex3f(h.p1.x,h.p1.y,0.0);
  glEnd();
}

void halfspaceD2draw::rotate(double const theta)
{
  pt2 z;
  z.x = h.p1.x - h.p0.x;
  z.y = h.p1.y - h.p0.y;
  double r = z.distance();
    
  alpha += theta;
//cout << SHOW(alpha) << endl;
  z.x = r*cos(alpha);
  z.y = r*sin(alpha);
  h.p1.x = z.x + h.p0.x;
  h.p1.y = z.y + h.p0.y;

  h.normalcalculate();
}