Research Of Real-time Cloth Animation Based On Region Division

With the rapid development of 3D Internet Applications,more and more demands on cloth animation in the virtual environment are raised.No matter in the computer 3D games,or in 3D films and televisions,peoples' demand for high reality and strong interactivity of animation is becoming higher and higher.Many scholars have made many remarkable achievements after many years' researches.However,the existing technologies are difficult to meet the high real-time and high realistic requirement.In the cloth animation technology,there are two key evaluation indicators,one is real-time of simulation,the other is the sense of reality of simulation.But these two factors in cloth animation is a contradictory,the basis of realism is complex physical computing,which is affecting the real-time of simulation.As a result,how to balance these two factors and to obtain an effective comprise is still a problem needed to be resolved so far.Based on the study background and problem above,this paper discusses the key technologies which used in cloth animation.Firstly,cloth modeling methods,forces analysis in the mass-spring model and numerical methods are compared and analyzed.Then the dynamic equation is established,and the Euler implicit method is selected.Finally,a method based regional pretreatment is used to detect the cloth collision.The specific work done in this paper is as follows:Regional division strategy of cloth is studied,and a new method of region division is proposed.According to the distance between cloth and other objects,cloth is divided into three regions,which are geometric region,weak physical region and strong physical region.Different simulation methods are use in different regions to make sure that maximize the simulation efficiency and enhance real-time performance on the basis of keeping sense of reality.The principle of physical methods are studied,and “weak physical” method is proposed.Based on the traditional physical method of simulation,combined with the special properties of some regions of the cloth,the traditional physical method is simplified.Some regions of the cloth has less physical details,there are few wrinkles even iftraditional physical method is used.So the simplified physical method can not only reduce the amount of computation,but also improve simulation efficiency,the sense of reality is not weakened as well.AABB algorithm is studied,and a improved AABB algorithm based on region pretreat is proposed.This algorithm simplifies the AABB algorithm by pretreatment,the minimum geometric elements with similarity are collocated together at the time of collision,and some of these elements are in the AABB tree's leaf node as a whole.This algorithm is helpful to improve the computational performance of the system and the real-time performance of cloth animation is further enhanced.In summary,this paper focuses on the idea of enhancing the real-time simulation by keeping sense of reality,proposes two optimized cloth animation algorithms,and verifies the practicability of them by simulation experiments.The research results of this paper will not only provide new theories for the production of cloth animation,but also have important significance for the fundamental theories and techniques in virtual reality,3D games and films fields.