public Body create(double rx, double ry, double rz) throws IOException{
		// gĂȂVAio[𔭍sāAVBody쐬ĕԂ
		for(int n=0; n<Integer.MAX_VALUE; ++n){
			++latestSerialNumber;
			if(!serialNumberMap.containsValue(latestSerialNumber)){
				GPUTexture[] textures = {
						getTexture("res/johnny.png"),
						getTexture("res/johnny_ahe.png"),
						getTexture("res/johnny_pangmi.png"),
				};
				Body newBody = new Body(latestSerialNumber, textures, rx, ry, rz);
				serialNumberMap.put(newBody, latestSerialNumber);
				return newBody;
			}
		}

		// 21܂烁pNƎv̂ŁAgc点čČƂ͂Ȃ
		// ꉞG[悤ɂĂ
		throw new Error("too many bodys.");
	}