/****************************************************************************

 Copyright (C) 2002-2006 Gilles Debunne (Gilles.Debunne@imag.fr)

This file is part of the QGLViewer library.
 Version 2.2.4-1, released on December 12, 2006.

 http://artis.imag.fr/Members/Gilles.Debunne/QGLViewer

 libQGLViewer 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 2 of the License, or
 (at your option) any later version.

 libQGLViewer 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 for more details.

 You should have received a copy of the GNU General Public License
 along with libQGLViewer; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

*****************************************************************************/

#include "cameraViewer.h"

using namespace qglviewer;

CameraViewer::CameraViewer(Camera* camera) : c(camera) {};

void CameraViewer::draw()
{
  // Exactly the same draw than for 'Viewer'. The two viewers could also share a 'Scene' instance.
  const float nbSteps = 200.0;

  glBegin(GL_QUAD_STRIP);
  for (int i=0; i<nbSteps; ++i)
    {
      const float ratio = i/nbSteps;
      const float angle = 21.0f*ratio;
      const float c = cos(angle);
      const float s = sin(angle);
      const float r1 = 1.0f - 0.8f*ratio;
      const float r2 = 0.8f - 0.8f*ratio;
      const float alt = ratio - 0.5f;
      const float nor = 0.5f;
      const float up = sqrt(1.0f-nor*nor);
      glColor3f(1.0f-ratio, 0.2f , ratio);
      glNormal3f(nor*c, up, nor*s);
      glVertex3f(r1*c, alt, r1*s);
      glVertex3f(r2*c, alt+0.05f, r2*s);
    }
  glEnd();

  // Draws the other viewer's camera
  glDisable(GL_LIGHTING);
  glLineWidth(4.0);
  glColor4f(1.0, 1.0, 1.0, 0.5);
  c->draw();
  glEnable(GL_LIGHTING);
}

void CameraViewer::init()
{
  // Places the cameraViewer's camera far away in order to see the (other viewer) camera.
  if (!restoreStateFromFile())
  {
    // Make near and far planes much further from scene in order not to clip c's display.
	camera()->setZClippingCoefficient(50.0);
    camera()->setViewDirection(qglviewer::Vec(0.0, -1.0, 0.0));
    showEntireScene();
  }

  // Enable semi-transparent culling planes
  glEnable(GL_BLEND);
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
}