source: orxonox.OLD/branches/atmospheric_engine/src/lib/graphics/effects/volfog_effect.cc @ 7558

/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   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, or (at your option)
   any later version.

### File Specific:
   main-programmer: hdavid, amaechler
*/

#include "volfog_effect.h"

#include "util/loading/load_param.h"
#include "util/loading/factory.h"

#include "glincl.h"
#include "shell_command.h"

using namespace std;

CREATE_FACTORY(VolFogEffect, CL_VOLFOG_EFFECT);

VolFogEffect::VolFogEffect(const TiXmlElement* root)
{
  this->setClassID(CL_VOLFOG_EFFECT, "VolFogEffect");

  if (root != NULL)
    this->loadParams(root);

  // Initialize Effect
  this->init();

  // Activate Effect
  this->activate();
}


VolFogEffect::~VolFogEffect()
{
  this->deactivate();
}

void VolFogEffect::loadParams(const TiXmlElement* root)
{
  WeatherEffect::loadParams(root);
}

bool VolFogEffect::init()
{
  PRINTF(0)("Initalize VolFogEffect\n");

  // Set fog color
  float fogColor[4] = {0.2, 0.2, 0.2, 1.0};

  // glClearColor(0.0, 0.0, 0.0, 1.0);  //sets bg color?!

  /* set up fog params */       
  glEnable(GL_FOG);                                             // Enable Fog
  glFogi(GL_FOG_MODE, GL_LINEAR);                               // Fog Fade Is Linear
  glFogfv(GL_FOG_COLOR, fogColor);                              // Set The Fog Color
  glFogf(GL_FOG_START, 0.0f);                                   // Set The Fog Start
  glFogf(GL_FOG_END, 1.0f);                                     // Set The Fog End
  glFogi(GL_FOG_COORDINATE_SOURCE_EXT, GL_FOG_COORDINATE_EXT);
  // glHint(GL_FOG_HINT, GL_NICEST);                            // Per-Pixel Fog Calculation

  /* enable texturing & set texturing function */
  // glEnable(GL_TEXTURE_2D);
  // glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

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

  char extensions[ 16384 ];
  char Extension_Name[] = "GL_EXT_fog_coord";
  char *buf;

  sprintf( extensions, "%s", (char *)glGetString( GL_EXTENSIONS ) );
  buf = strtok( extensions, " " );
  while( buf != NULL )
  {
    if( !strcmp( Extension_Name, buf ) )
    {
      PRINTF(0)( "%s found, great.\n", Extension_Name );
      return true;
    }
    buf = strtok( NULL, " " );
  }

  PRINTF(0)( "%s\n", (char *)glGetString( GL_EXTENSIONS ) );
  PRINTF(0)( "%s not found.\n", Extension_Name );
  return false;
}


bool VolFogEffect::activate()
{
  PRINTF(0)("Activating VolFogEffect\n");
}

bool VolFogEffect::deactivate()
{
  PRINTF(0)("Deactivating VolFogEffect\n");
}


/**
 * draws the effect, if needed
 */
void VolFogEffect::draw() const
{
        //glPushAttrib(GL_ENABLE_BIT);
        
        /* clear all pixels in colour buffer */
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        // glPushAttrib(GL_ENABLE_BIT);

        glEnable(GL_BLEND);
        glBlendFunc(GL_SRC_ALPHA, GL_DST_ALPHA);

        //glLoadIdentity ();    // Reset The Modelview Matrix

        // glBindTexture(GL_TEXTURE_2D, 0);
        /* draw the panels */
        glBegin(GL_QUADS); // Floor
                glFogCoordfEXT(0.0f);   glVertex3f(0.0f,0.0f,0.0f);
                glFogCoordfEXT(0.0f);   glVertex3f(100.0f,0.0f,0.0f);
                glFogCoordfEXT(0.0f);   glVertex3f(100.0f,0.0f, 100.0f);
                glFogCoordfEXT(0.0f);   glVertex3f(0.0f,0.0f, 100.0f);
        glEnd();

        glBegin(GL_QUADS); // Roof
                glFogCoordfEXT(5.0f);   glVertex3f(0.0f, 100.0f,0.0f);
                glFogCoordfEXT(5.0f);   glVertex3f( 100.0f, 100.0f,0.0f);
                glFogCoordfEXT(5.0f);   glVertex3f( 100.0f, 100.0f, 100.0f);
                glFogCoordfEXT(5.0f);   glVertex3f(0.0f, 100.0f, 100.0f);
        glEnd();

        glBegin(GL_QUADS); // Back Wall
                glFogCoordfEXT(0.0f);   glVertex3f(0.0f,0.0f,0.0f);
                glFogCoordfEXT(0.0f);   glVertex3f( 100.0f,0.0f,0.0f);
                glFogCoordfEXT(5.0f);   glVertex3f( 100.0f, 100.0f,0.0f);
                glFogCoordfEXT(5.0f);   glVertex3f(0.0f, 100.0f,0.0f);
        glEnd();

        glBegin(GL_QUADS); // Front Wall
                glFogCoordfEXT(0.0f);   glVertex3f(0.0f,0.0f,100.0f);
                glFogCoordfEXT(0.0f);   glVertex3f( 100.0f,0.0f,100.0f);
                glFogCoordfEXT(5.0f);   glVertex3f( 100.0f, 100.0f,100.0f);
                glFogCoordfEXT(5.0f);   glVertex3f(0.0f, 100.0f,100.0f);
        glEnd();

        glBegin(GL_QUADS); // Right Wall
                glFogCoordfEXT(0.0f);   glVertex3f( 100.0f,0.0f, 100.0f);
                glFogCoordfEXT(5.0f);   glVertex3f( 100.0f, 100.0f, 100.0f);
                glFogCoordfEXT(5.0f);   glVertex3f( 100.0f, 100.0f,0.0f);
                glFogCoordfEXT(0.0f);   glVertex3f( 100.0f,0.0f,0.0f);
        glEnd();

        glBegin(GL_QUADS); // Left Wall
                glFogCoordfEXT(0.0f);   glVertex3f(0.0f,0.0f, 100.0f);
                glFogCoordfEXT(5.0f);   glVertex3f(0.0f, 100.0f, 100.0f);
                glFogCoordfEXT(5.0f);   glVertex3f(0.0f, 100.0f,0.0f);
                glFogCoordfEXT(0.0f);   glVertex3f(0.0f,0.0f,0.0f);
        glEnd();
        
        /* process all buffered OpenGL commands */
        glFlush();

        // glPopAttrib();
        // glPopAttrib();
}


/**
 * ticks the effect if there is any time dependancy
 */
void VolFogEffect::tick(float dt)       
{
}