Method and apparatus for inserting external transformations into computer animations

This invention relates to the field of computer graphics, and more specifically, to modeling and/or simulating the behavior and motion of real-world articulated objects such as humans, animals and birds in real-time 3-dimensional video games and other interactive contexts. Still more particularly, this invention relates to a unique solution to the problem of efficiently inserting external matrix transformations (e.g., generated in real time) to computer-modeled animations and/or changing animation sequences at an arbitrary point. Transformation matrices describing the motion of an articulated reference object specify translations of the reference object and/or its articulated parts, and are relative to the origin of the object's coordinate system. During the real-time animation process, a connection matrix is saved to represent the current transformation status of the animated object. This connection matrix being obtained by continuously concatenating an external transformation (if any) with the next animation step. This process allows efficient insertion of external transformations (e.g., resulting from operating real-time interactive user controls). Use of absolute transformations to develop the connection matrix allows a first animation sequence to be interrupted at any arbitrary point and immediately, smoothly followed by a second animation sequence (e.g., walking can be interrupted at any time and turned into running, jumping, etc.).