public String animate(double speedmul) {
		String ret = getCurrentFrame();
		if (running) {
			phase += speed*speedmul;
			while (phase >= 1.0) {
				phase -= 1.0;
				framenr += increment;
				if (!pingpong) {
					if (framenr >= frames.length) framenr -= frames.length;
					if (framenr < 0)              framenr += frames.length;
				} else {
					if (framenr >= frames.length) {
						framenr -= 2*increment;
						increment = -increment;
					}
					if (framenr < 0) {
						framenr -= 2*increment;
						increment = -increment;
					}
				}
			}
		}
		return ret;
	}