/*  $Id: nightvision.cpp 1218 2006-01-12 02:55:49Z grumbel $
**   __      __ __             ___        __   __ __   __
**  /  \    /  \__| ____    __| _/_______/  |_|__|  | |  |   ____
**  \   \/\/   /  |/    \  / __ |/  ___/\   __\  |  | |  | _/ __ \
**   \        /|  |   |  \/ /_/ |\___ \  |  | |  |  |_|  |_\  ___/
**    \__/\  / |__|___|  /\____ /____  > |__| |__|____/____/\___  >
**         \/          \/      \/    \/                         \/
**  Copyright (C) 2005 Ingo Ruhnke <grumbel@gmx.de>
**
**  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 2
**  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 for more details.
** 
**  You should have received a copy of the GNU General Public License
**  along with this program; if not, write to the Free Software
**  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
**  02111-1307, USA.
*/

#include "globals.hpp"
#include "random.hpp"
#include "math/matrix.hpp"
#include "display/vertex_array_drawing_request.hpp"
#include "display/texture_manager.hpp"
#include "nightvision.hpp"

Nightvision::Nightvision(FileReader& props)
  : nightvision("images/nightvision.sprite")
{
  name = "nightvision";
  noise = Texture("images/noise.png");
  noise.set_wrap(GL_REPEAT);
  noise.set_filter(GL_LINEAR);
}

Nightvision::~Nightvision()
{
}

void
Nightvision::draw(SceneContext& sc)
{
  // reset the modelview, so we can draw in screen coordinates
  sc.light().push_modelview();
  sc.light().set_modelview(Matrix::identity());

  // try to stay above everything else with large z value
  if (1)
    {
      nightvision.set_alpha(1.0f);
      nightvision.set_blend_func(GL_ONE, GL_ZERO);
      sc.light().draw(nightvision, Vector(0, 0), 10000);
    }

  if (1)
    {
      VertexArrayDrawingRequest* array = new VertexArrayDrawingRequest(Vector(0, 0), 10000,
                                                                       sc.light().get_modelview());
      array->set_mode(GL_QUADS);
      array->set_texture(noise);
      array->set_blend_func(GL_DST_COLOR, GL_ZERO);

      float u = rnd.drand()/0.5f;
      float v = rnd.drand()/0.5f;
      float w = 4.0f/6.0f;
      float h = 3.0f/6.0f;

      array->texcoord(u, v);
      array->vertex(0, 0);

      array->texcoord(u + w, v);
      array->vertex(800, 0);

      array->texcoord(u + w, v + h);
      array->vertex(800, 600);

      array->texcoord(u, v + h);
      array->vertex(0, 600);
      
      if (0) // second noise level
        {
          u = rnd.drand();
          v = rnd.drand();
          float size = 4.0f;

          array->texcoord(u, v);
          array->vertex(0, 0, 1.0f);

          array->texcoord(u + size, v);
          array->vertex(800, 0, 1.0f);

          array->texcoord(u + size, v + size);
          array->vertex(800, 600, 1.0f);

          array->texcoord(u, v + size);
          array->vertex(0, 600, 1.0f);
        }

      sc.light().draw(array);
    }
  sc.light().pop_modelview();

  if (1)
    {
      // FIXME: might be better to copy the highlight over to the
      // color layer, however that would require some changes to the
      // DrawingContext structure
      sc.highlight().clear();

      sc.highlight().push_modelview();
      sc.highlight().set_modelview(Matrix::identity());
      nightvision.set_alpha(0.5f);
      nightvision.set_blend_func(GL_SRC_ALPHA, GL_ONE);
      sc.highlight().draw(nightvision, Vector(0, 0), 10000);
      sc.highlight().pop_modelview();
    }
}

void
Nightvision::update(float )
{
}

/* EOF */