fprintf(fi," (music \"%s\")\n", song_title.c_str());
fprintf(fi," (background \"%s\")\n", bkgd_image.c_str());
fprintf(fi," (particle_system \"%s\")\n", particle_system.c_str());
fprintf(fi," (music \"%s\")\n", song_title.c_str());
fprintf(fi," (background \"%s\")\n", bkgd_image.c_str());
fprintf(fi," (particle_system \"%s\")\n", particle_system.c_str());