#ifndef FBO_H
#define FBO_H
#include <GL/glew.h>
//#include <SDL/SDL.h>
class CFBO
{
    public:
    CFBO(int, int, int);
    ~CFBO();
    //void SetTexture(int, GLuint*);
    GLuint GetTexture(int);
    void Set(int);
    void Reset();
    int GetnFBO();
    protected:
    int nfbo;
    GLuint tex[16], rbo[16], fbo[16], w, h;
};
#endif

#include "FBO.h"
CFBO::CFBO(int nb, int width, int height)
{
    /*Constructeur de la Class CFBO
    nb représente le nombre de FrameBufferObj a créer
    width et height sont les dimensions qui sont respectivement largeur et hauteur
    Il faut savoir que nb FrameBufferObj seront crée a la même dimension width*height*/
    ///GENERATION
    glGenTextures(nb, tex);
    glGenFramebuffersEXT(nb, fbo);
    glGenRenderbuffersEXT(nb, rbo);
    for(int i=0; i<nb; i++)
    {
    ///TEXTURE INIT
    glEnable(GL_TEXTURE_2D);
   glBindTexture(GL_TEXTURE_2D,tex[i]);
   glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, width, height,0 , GL_RGB, GL_INT, NULL);
   /*width et height doivent etre egaux et des puissance de 2.
   Remplacez GL_TEXTURE_2D par GL_TEXTURE_RECTANGLE_ARB pour
   pouvoir utiliser des textures avec plus de liberté.
   Cependant, attention a son utilisation, référencez vous pour
   l'utilisation de GL_TEXTURE_RECTANGLE_ARB*/
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);//si vous voulez un rendu pixelisé comme Minecraft, remplacez GL_LINEAR par GL_NEAREST
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);//idem
   glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP_TO_EDGE);
   glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_CLAMP_TO_EDGE);
    //UNBIND TEXTURE
   glBindTexture(GL_TEXTURE_2D,0);

    ///FBO BIND
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo[i]);
    ///Render Buffer BIND & ASSOC -> FBO
    glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, rbo[i]);
    glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT, width, height);
    glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, 0);
    ///ASSIGNATION Texture et Render Buffer
    glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,GL_TEXTURE_2D, tex[i], 0);
    glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT,GL_RENDERBUFFER_EXT, rbo[i]);
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
    }
    nfbo=nb;
    w=width;
    h=height;
}
CFBO::~CFBO()
{
    /*Destructeur de la Class CFBO
    Il est très conseillé d'utilisé lorsque vous n'en ayez plus besoin*/
    glDeleteFramebuffersEXT(nfbo, fbo);
    glDeleteRenderbuffersEXT(nfbo, rbo);
    glDeleteTextures(nfbo, tex);
}
void CFBO::Set(int i)
{
    /*meme utilisation que surface_set_target()
    i représente l'id de la texture dans l'instance crée
    variant de 0 a 15*/
    glFlush();
    glEnable(GL_TEXTURE_2D);
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fbo[i]);
    glBindTexture(GL_TEXTURE_2D,0);
    glViewport(0, 0, w, h);
}
void CFBO::Reset()
{
    /*meme utilisation que surface_set_target()
    nul besoin de préciser quel id a reset car elle agit sur toute*/
    glFlush();
    glDisable(GL_TEXTURE_2D);
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
}
GLuint CFBO::GetTexture(int i)
{
    /*Retourne l'id sous forme "GLuint" de la texture d'id i*/
    return tex[i];
}
int CFBO::GetnFBO()
{
    /*Retourne le nombre de FrameBufferObj que l'on a construit dans le constructeur -> nb*/
    return nfbo;
}

#include <GL/glew.h>
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <SDL/SDL.h>
#include "sdlglutils.h"
#include "FBO.h"

///Variable
int Largeur=1000, Hauteur=800, FPS=0;
int Wfbo=256, Hfbo=256;
const SDL_VideoInfo* VideoInfo;
char continuer=1;
GLuint text;
CFBO *FboObj;
///Fonctions
int FPSGet();
void FPSControl(float);
void drawCube(float x1,float y1,float z1,float x2,float y2,float z2,GLuint tex);

int main(int argc, char** argv)
{
    std::cout<<"Chargement...\n";

    SDL_Surface *window;
    SDL_Init(SDL_INIT_VIDEO);
    ****("SDL_VIDEO_WINDOW_POS=center");
    SDL_WM_SetCaption("Test du FrameBuffer Object",NULL);
    VideoInfo = SDL_GetVideoInfo();
    window = SDL_SetVideoMode(Largeur, Hauteur, 32, SDL_OPENGL|SDL_DOUBLEBUF);
    GLenum code = glewInit();
    text=loadTexture("tex2.png",1);
    if(code != GLEW_OK)
    {
        std::cout<<"erreur glewInit() : "<<code;
        exit(32);
    }
    if (text==NULL)
    {
        std::cout<<"erreur Texture non chargée : "<< std::endl;
        exit(33);
    }
    else
    {std::cout<<"texture : "<<text<<std::endl;}
    glEnable(GL_DEPTH_TEST);


    ///Partie FBO
    GLenum status;
    status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
    SDL_Event event;
    status==GL_FRAMEBUFFER_COMPLETE_EXT?
   std::cout << " - FBO supporté - \n":
   std::cout << " - FBO non supporté - \n Arrété\n";
   if (status!=GL_FRAMEBUFFER_COMPLETE_EXT)exit(1);

   int taille_max;
   glGetIntegerv(GL_MAX_RECTANGLE_TEXTURE_SIZE_ARB,&taille_max);
   std::cout << " Taille max de texture supportée : " << taille_max << std::endl;
   //GLuint fbo, rbo, texfbo;
    //FBORenderCreate(1, &fbo, &rbo, &texfbo, 256, 256);
    std::cout<<"Nouvelle Classe FBO : FboObj"<<std::endl;
    FboObj = new CFBO(2,Wfbo, Hfbo);

    std::cout<<"Chargée\n";
    //std::cout << "fbo : " << &fbo << "\ntexture : " << &texfbo1 << std::endl;
    while (continuer)
    {
        SDL_PollEvent(&event);
        switch (event.type)
        {
        case SDL_QUIT:
                continuer = false;
        break;
        case SDL_KEYDOWN:
            if ((event.key.keysym.sym)==SDLK_ESCAPE) continuer=0;
        break;
        }
        FPS=FPSGet();
        char ch[100];
        sprintf(ch, "Test du FrameBuffer Object %d FPS", FPS);
        SDL_WM_SetCaption(ch,NULL );
        glMatrixMode(GL_MODELVIEW);
        glLoadIdentity();
        glMatrixMode( GL_PROJECTION );
        glLoadIdentity();
        //gluPerspective(90,(float)Largeur/Hauteur,0.1f,500);
        //glFrustum(0,0,HAUTEUR,LARGEUR, 0.1f, 500);
        //glClear(GL_DEPTH_BUFFER_BIT|GL_COLOR_BUFFER_BIT);
        static float xx=0;
        xx+=0.7;

        //FBOSet();
        FboObj->Set(0);
        ///draw 3D ON FBO TEX0
        glClearColor(0.0f, 0.5f, 0.0f, 0.0f);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        //glClearColor(0.0f, 0.0f, 1.0f, 0.0f);

        glPushMatrix();
        gluPerspective(90, (float)Hfbo/Wfbo,1.0F, 100.0F);
        gluLookAt(0.0F, 0.0F, 3.0F, 0.0F, 0.0F, 0.0F, 0.0F, 1.0F, 0.0F);
        glRotatef(xx/5, 1, 0, 0);
        glRotatef(xx/5, 0, 1, 0);
        glBindTexture(GL_TEXTURE_2D,text);
        glColor3f(1.0F,1.0F,1.0F);
        drawCube(-1,-1,-1,1,1,1,text);
        glEnd();
        glPopMatrix();
        //drawCube(-1,-1,-1,1,1,1,0);
        ///draw 3D OFF FBO TEX0
        FboObj->Set(1);
        ///draw 3D ON FBO TEX1
        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        glPushMatrix();
        gluPerspective(90, (float)Hfbo/Wfbo,1.0F, 100.0F);
        gluLookAt(0.0F, 0.0F, 1.0F, 0.0F, 0.0F, 0.0F, 0.0F, 1.0F, 0.0F);

        //glRotatef(90, 0, 1, 0);
        glEnable(GL_TEXTURE_2D);
        glBindTexture(GL_TEXTURE_2D,FboObj->GetTexture(0));

        glEnable(GL_BLEND);glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glColor4f(1.0F,1.0F,1.0F, 0.1F);
        glBegin(GL_QUADS);
        for(int iy=-2;iy<2;iy++)
        {
        for(int ix=-2;ix<2;ix++)
        {
        glTexCoord2i(0,0);    glVertex3f(-1.0F+0.008F*ix,-1.0F+0.008F*iy,0.0001F*(ix+iy*10));
        glTexCoord2i(0,1);    glVertex3f(-1.0F+0.008F*ix, 1.0F+0.008F*iy,0.0001F*(ix+iy*10));
        glTexCoord2i(1,1);    glVertex3f( 1.0F+0.008F*ix, 1.0F+0.008F*iy,0.0001F*(ix+iy*10));
        glTexCoord2i(1,0);    glVertex3f( 1.0F+0.008F*ix,-1.0F+0.008F*iy,0.0001F*(ix+iy*10));
        }
        }
        glDisable(GL_BLEND);
        glEnd();
        glBindTexture(GL_TEXTURE_2D,0);
        //drawCube(-1,-1,-1,1,1,1,texfbo);
        glPopMatrix();
        FboObj->Reset();
        glViewport(0,0,Largeur, Hauteur);
        ///draw 3D ON NO-FBO
        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        glPushMatrix();
        gluPerspective(90, (float)Largeur/Hauteur,1.0F, 100.0F);
        gluLookAt(0.0F, 0.0F, 2.0F, 0.0F, 0.0F, 0.0F, 0.0F, 1.0F, 0.0F);
        glColor4f(1.0F,1.0F,1.0F, 1.0F);
        glEnable(GL_TEXTURE_2D);
        glBindTexture(GL_TEXTURE_2D,FboObj->GetTexture(1));
        glBegin(GL_QUADS);
        glTexCoord2i(0,0);  glVertex3f(-2.0F,-1.0F,0.0F);
        glTexCoord2i(0,1);  glVertex3f(-2.0F, 1.0F,0.0F);
        glTexCoord2i(1,1);  glVertex3f( 0.0F, 1.0F,0.0F);
        glTexCoord2i(1,0);  glVertex3f( 0.0F,-1.0F,0.0F);
        glEnd();
        glPopMatrix();
        ///draw 3D OFF NO-FBO

        glMatrixMode(GL_PROJECTION);
        glPopMatrix();
        glMatrixMode(GL_MODELVIEW);
        glPopMatrix();
        glEnable(GL_DEPTH_TEST);

        glFlush();
        SDL_GL_SwapBuffers();
        FPSControl(1230);
        //XFlush(dpy);
    }
    delete FboObj; FboObj=NULL;
    SDL_Quit();
    return 0;
}
int FPSGet()
{
    static int tcount=0, tP=SDL_GetTicks(), fps=0;
    tcount++;
    int tA=SDL_GetTicks();
    if (tA-tP>1000.0f)
    {
        fps=tcount;
        tcount=0;
        tP=tA;
    }
    return fps;
}
void FPSControl(float fps)
{
    static int tP=0;
    int tA = SDL_GetTicks();
    //int _fps=tA - tP;
    if (tA - tP > (1000.0f/fps))
    {tP = tA;}
    else
    {SDL_Delay(float(1000.0f/fps) - (tA - tP));}

}
void drawCube(float x1,float y1,float z1,float x2,float y2,float z2,GLuint tex)
{
    glBindTexture(GL_TEXTURE_2D, tex);
    glBegin(GL_QUADS);
    glTexCoord2d(0,0); glVertex3d(x1,y1,z1);
    glTexCoord2d(0,1); glVertex3d(x1,y2,z1);
    glTexCoord2d(1,1); glVertex3d(x2,y2,z1);
    glTexCoord2d(1,0); glVertex3d(x2,y1,z1);

    glTexCoord2d(0,0); glVertex3d(x1,y1,z2);
    glTexCoord2d(0,1); glVertex3d(x1,y2,z2);
    glTexCoord2d(1,1); glVertex3d(x2,y2,z2);
    glTexCoord2d(1,0); glVertex3d(x2,y1,z2);

    glTexCoord2d(1,0); glVertex3d(x1,y1,z1);
    glTexCoord2d(1,1); glVertex3d(x1,y1,z2);
    glTexCoord2d(0,1); glVertex3d(x2,y1,z2);
    glTexCoord2d(0,0); glVertex3d(x2,y1,z1);

    glTexCoord2d(0,0); glVertex3d(x1,y2,z1);
    glTexCoord2d(0,1); glVertex3d(x1,y2,z2);
    glTexCoord2d(1,1); glVertex3d(x2,y2,z2);
    glTexCoord2d(1,0); glVertex3d(x2,y2,z1);

    glTexCoord2d(0,0); glVertex3d(x1,y1,z1);
    glTexCoord2d(0,1); glVertex3d(x1,y1,z2);
    glTexCoord2d(1,1); glVertex3d(x1,y2,z2);
    glTexCoord2d(1,0); glVertex3d(x1,y2,z1);

    glTexCoord2d(1,0); glVertex3d(x2,y1,z1);
    glTexCoord2d(1,1); glVertex3d(x2,y1,z2);
    glTexCoord2d(0,1); glVertex3d(x2,y2,z2);
    glTexCoord2d(0,0); glVertex3d(x2,y2,z1);
    glEnd();
}