A Facial Rigging Survey

Rigging is the process of setting up a group of controls to operate a 3D model, analogous to the strings of a puppet. It plays a fundamental role in the animation process as it eases the manipulation and editing of expressions, but rigging can be very laborious and cumbersome for an artist. This difficulty arises from the lack of a standard definition of what is a rig and the multitude approaches on how to setup a face. This survey presents a critical review on the fundamentals of rigging, with an outlook of the different techniques, their uses and problems. It describes the main problems that appear when preparing a character for animation. This paper also gives an overview of the role and relationship between the rigger and the animator. Continues with an exhaustive analysis of the published literature and previous work, centered on the facial rigging pipeline. Finally, the survey discusses future directions of facial rigging.