1. An animation system, comprising: a server system connected to a communication network and configured to communicate with a user device that is also connected to the communication network; wherein the server system is configured to generate a user interface that is accessible via the communication network; wherein the server system is configured to receive high level descriptions of desired sequences of motion via the user interface; wherein the server system is configured to generate synthetic motion data based on the high level descriptions and to concatenate the synthetic motion data; wherein the server system is configured to stream the concatenated synthetic motion data to a rendering engine on the user device; and wherein the user device is configured to render a 3D character animated using the streamed synthetic motion data.