void Sprite::Update(double deltaTime)
{
    glPushMatrix();
        glTranslatef(position.x, position.y, 0.0f);
        glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
    glPopMatrix();
}

uniform mat4 u_ViewMatrix;
uniform float u_Size;
attribute vec2 a_TextureCoord;
varying vec2 v_TextureCoord;
varying vec3 v_VertexCoord;
varying vec4 v_Position;

void main() {
  v_TextureCoord = a_TextureCoord;
  v_Position =  u_ViewMatrix * vec4(0.0,0.0,0.0,1.0);
  v_VertexCoord = (vec3(a_TextureCoord[0] - 0.5, (a_TextureCoord[1] - 0.5) * -1.0 , 0.0));
  v_VertexCoord = v_VertexCoord * u_Size;
  gl_Position = v_Position + vec4(v_VertexCoord, 0.0);
}

GLuint LoadTexture(const char *filename)
{
  GLuint format;
  GLuint texture;
  GLuint bpp; //BytesPerPixel

  //ez a Tga osztály, ezen belül tölti be magának a tga fájlt
  CTargaImage* image = new CTargaImage();

  //betöltés
  if(!image->Load(filename)) return 0;

  if(image->GetTgaHeader().bpp == 24)
  {
  format = GL_RGB;
  }
  else
  if(image->GetTgaHeader().bpp == 32)
  {
  format = GL_RGBA;
  }

  //itt elvileg minden helyesen van, mégse lesz belőle textúra csak egy fehér négyzet
  glGenTextures(1, &texture);
  glBindTexture(GL_TEXTURE_2D, texture);

  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
  glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

  glTexImage2D( GL_TEXTURE_2D,
0,
format,
image->GetWidth(),
image->GetHeight(),
0,
format, GL_UNSIGNED_BYTE, image->GetImage() );

  return texture;
}

void RenderTexture(const GLuint& texture, Vector2d pos, float w, float h)
{
float x2 = pos.x + w;
float y2 = pos.y + h;

glBindTexture(GL_TEXTURE_2D, texture);

glBegin(GL_QUADS);
glTexCoord2f(0.0F, 0.0F);
glVertex2f(pos.x, pos.y);
glTexCoord2f(1.0F, 0.0F);
glVertex2f(x2, pos.y);
glTexCoord2f(1.0F, 1.0F);
glVertex2f(x2, y2);
glTexCoord2f(0.0F, 1.0F);
glVertex2f(pos.x, y2)
glEnd();
}

void RenderTGA(CTargaImage* tgaImage, Vector2d pos)
{
glRasterPos2i(pos.x, pos.y);
glDrawPixels( (int)(tgaImage->GetWidth()),
(int)(tgaImage->GetHeight()),
GL_RGBA,
GL_UNSIGNED_BYTE,
tgaImage->GetImage() );
}

#define GL_GLEXT_PROTOTYPES 1
#define GLX_GLXEXT_PROTOTYPES 1

void setPixel(GLubyte* ptr,int r,int g,int b,int x,int y)
{

long int i;
    i=4*(512*(y+255)+(x+256));

     *(ptr+i)=b; //kék
     *(ptr+i+1)=g; //zöld
     *(ptr+i+2)=r; //piros
     *(ptr+i+3)=0;

}

imageData=(GLubyte*)malloc(512*4*512*sizeof(GLubyte));
memset(imageData,0, 512*512*4); //nulláza a tömböt


    // init 1 texture objects
    glGenTextures(1, &textureId);
    glBindTexture(GL_TEXTURE_2D, textureId);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 512, 512,0, PIXEL_FORMAT, GL_UNSIGNED_BYTE, (GLvoid*)imageData);

    glBindTexture(GL_TEXTURE_2D, 0);


       // create 1 pixel buffer objects, you need to delete them when program exits.
        // glBufferDataARB with NULL pointer reserves only memory space.
        glGenBuffersARB(1, pboIds);
        glBindBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, pboIds[0]);
        glBufferDataARB(GL_PIXEL_UNPACK_BUFFER_ARB, 4*512*512*sizeof(GLubyte), NULL, GL_STREAM_DRAW_ARB);
       glBindBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB,0);


//köti a PBO-t
glBindBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB,pboIds[0]);


//0-kkal tölti fel a PBO-t
glBufferDataARB(GL_PIXEL_UNPACK_BUFFER_ARB, 4*512*512*sizeof(GLubyte)  ,0, GL_STREAM_DRAW_ARB);

//lekéri a PBO tartalmára mutató mutatót a módosításhoz
GLubyte* ioMem = (GLubyte*)glMapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, GL_WRITE_ONLY_ARB);
if(ioMem)
  {
//buffer: 4*szélesség*magasság
setPixel(ioMem,40,150,160,0,0); //buffer,r,g,b,x,y

glUnmapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB);
  }

//köti a textúrát
glBindTexture(GL_TEXTURE_2D,textureId);

//átküldi a pbo tartalmát a textura objektumba
glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 512, 512, PIXEL_FORMAT, GL_UNSIGNED_BYTE,0);
//feloldja a PBO kötést
glBindBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, 0);


while(1)
{



glClear(GL_COLOR_BUFFER_BIT); //törli a képernyő és a mélységi buffert

    glMatrixMode(GL_MODELVIEW);

      /* reset modelview matrix to the identity matrix */
    glLoadIdentity();

      /* move the camera back three units */
     glTranslatef(0.0, 0.0, -2.0);

glBindTexture(GL_TEXTURE_2D, textureId);
    glColor4f(1, 1, 1, 1);
    glBegin(GL_QUADS);
    glNormal3f(0, 0, 1);
   glTexCoord2f(0.0f, 0.0f);
     glVertex3f(-2.0f, -2.0f, 0.0f);
  glTexCoord2f(1.0f, 0.0f);
    glVertex3f( 2.0f, -2.0f, 0.0f);
glTexCoord2f(1.0f, 1.0f);
     glVertex3f( 2.0f,  2.0f, 0.0f);
glTexCoord2f(0.0f, 1.0f);
    glVertex3f(-2.0f,  2.0f, 0.0f);
    glEnd();

glBindTexture(GL_TEXTURE_2D,0);

   glXSwapBuffers(dpy,win);
   XPending(dpy);
}