C++ > OpenGL SDL_TTF transparence

Text::Text(Ttf* font, const char* text, unsigned char r, unsigned char g, unsigned char b)
{
        SDL_Surface* s = NULL;
        SDL_Surface* socle = NULL;
        SDL_Color color = {r, g, b, 0};
        unsigned short w = 1, h = 1;

        s = TTF_RenderText_Blended(font->GetFont(), text, color);

        while (s->w > w)
                w = w << 1;

        while (s->h > h)
                h = h << 1;

        w < h ? w = h : h = w;
         
        if(s > 0)
        {
                socle = SDL_CreateRGBSurface(SDL_SWSURFACE, w, h, 32, s->format->Rmask, s->format->Gmask, s->format->Bmask, s->format->Amask);
                 
                SDL_BlitSurface(s, NULL, socle, NULL);

                glGenTextures(1, &id);
                glBindTexture(GL_TEXTURE_2D, id);
                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
                glTexImage2D(GL_TEXTURE_2D, 0, 4, socle->w, socle->h, 0, GL_BGRA_EXT, GL_UNSIGNED_BYTE, socle->pixels);
        }

        SDL_FreeSurface(s);
        SDL_FreeSurface(socle);
}