Character Body Expression in 3D Computer Animation: a New Posing Approach.

Abstract

Creation of 3D character animations is a complex and time-consuming process, and the character animator has to simultaneously consider a multitude of factors in order to create high quality expressive animation. The 12 Principles of Animation are traditionally considered as the main guidelines for creating high-grade character animation. The main focus of this research is the process of animating the 3D character’s body expression and the animator’s practice, particularly the Posing phase of the animation process. Although posing is not one of the 12 Principles of Animation, it can be considered as the superposition of a subset of those principles that the animator has to keep in mind, while creating key-poses for any specific movement of an animated character. Additional factors that should be considered by the animator during the Posing stage are body language and acting, along with the technicalities of the 3D character manipulation. Hence, Posing is regarded as an intricate process, making it rather challenging for the animator to avoid involuntary neglect of the large number of the aforementioned characteristics. This aspect of the 3D animation process is extremely important for the final creative result of the animation, in terms of character's expression, because if the key-poses are not well defined, the computer may not be able to generate sufficiently expressive animation. This would often result in work that may be subjectively judged as lower quality animations. This research developed the hypothesis that the key to create more expressive 3D character animation is located within Posing, in the Animation Blocking phase of the process. This thesis proposes that a systematisation of the Posing procedure taking advantage of certain Traditional Animation, Fine Arts and Acting concepts and their underlying rationale, can greatly benefit the animator. This thesis presents a new posing approach to 3D character animation, as a conceptual guideline which promotes the arrangement of the body parts into naturalistic patterns of expression. This is achieved by combining the concepts of Power Centre, Line of Action, Contrapposto and Serpentine Line in a systematic way, around a conceptual flow of force. These comprehensible high-level concepts make Posing and the animation process less complicated and more accessible. This allows animators of different levels to create more believable character body expressions in an easier and less time-consuming fashion, introducing better methods of more efficient workflows resulting in improved creative results over shorter periods of time. It is also demonstrated how the aforementioned concepts can be applied to a variety of animation styles – ranging from the more realistic to the more cartoonish ones. A prototype of a 3D Pose Tool was also developed, based on the rationale of the proposed approach, with the objective of being used as a visual guide for generation of new poses to be included in the case studies. Additionally, this tool produces visual evidence in the analysis of specific good and bad examples of character posing. This thesis, therefore, makes the argument that the proposed solution – whether accompanied with the complementary 3D Pose Tool or not – gives the animator the possibility to work the character body expression as a whole. Thus, avoiding stiffness and ensuring that the essential steps of posing are not neglected in the process. This was demonstrated with several cases, which give evidence of the usefulness of the approach as a contribution to create more expressive character animation and to produce it in a more efficient way.