source: orxonox.OLD/branches/atmospheric_engine/src/lib/graphics/effects/volfog_effect.cc @ 7679

/*
        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");
        
        if (glewInit() == GLEW_OK)
                PRINTF(0)("glewInit OK\n");
        else
                PRINTF(0)("glewInit failed\n");

        // Set fog color
        float fogColor[4] = {0.0, 1.0, 0.0, 1.0};

        /* 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);    // Set The Fog based on vertice coordinates
        // glHint(GL_FOG_HINT, GL_NICEST);                              // Per-Pixel Fog Calculation

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

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

        if (glewGetExtension("GL_EXT_fog_coord"))
        {
                PRINTF(0)("GL_EXT_fog_coord extension found\n");
                return true;
        }
        else
        {
                PRINTF(0)("GL_EXT_fog_coord extension NOT found\n");
                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);

        /* Enable blending */
        //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(1.0f);   glVertex3f(0.0f, 100.0f,0.0f);
                glFogCoordfEXT(1.0f);   glVertex3f( 100.0f, 100.0f,0.0f);
                glFogCoordfEXT(1.0f);   glVertex3f( 100.0f, 100.0f, 100.0f);
                glFogCoordfEXT(1.0f);   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(1.0f);   glVertex3f( 100.0f, 100.0f,0.0f);
                glFogCoordfEXT(1.0f);   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(1.0f);   glVertex3f( 100.0f, 100.0f,100.0f);
                glFogCoordfEXT(1.0f);   glVertex3f(0.0f, 100.0f,100.0f);
        glEnd();

        glBegin(GL_QUADS); // Right Wall
                glFogCoordfEXT(0.0f);   glVertex3f( 100.0f,0.0f, 100.0f);
                glFogCoordfEXT(1.0f);   glVertex3f( 100.0f, 100.0f, 100.0f);
                glFogCoordfEXT(1.0f);   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(1.0f);   glVertex3f(0.0f, 100.0f, 100.0f);
                glFogCoordfEXT(1.0f);   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();
}


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