Game Engine Architecture

499 Each joint data structure typically contains the following information: The • name of the joint, either as a string or a has ...

500 11. Animation Systems represented by a 4 × 4 or 4 × 3 matrix, or by an SQT data structure (scale, quaternion rotation and ve ...

501 unchanged, the entire arm will rotate about the shoulder in a rigid manner, as we’d expect. We sometimes use the term local ...

502 11. Animation Systems 11.3.2.1. Joint Scale Some game engines assume that joints will never be scaled, in which case Sj is s ...

503 The local pose of an entire skeleton can be represented as follows, where it is understood that the array m_aLocalPose is dy ...

504 11. Animation Systems In general, the global pose (joint-to-model transform) of any joint j can be writt en as follows: 0 jM ...

11.4. Clips 505 Game animation is diff erent. A game is an interactive experience, so one cannot predict beforehand how the char ...

506 11. Animation Systems 11.4.1.1. Pose Interpolation and Continuous Time It’s important to realize that the rate at which fram ...

507 1, 2, 3, and so on—there’s never any need to fi nd a character’s pose on frame 3.7, for example. So in fi lm animation, the ...

508 11. Animation Systems 11.4.1.4. Frames, Samples and Looping Clips When a clip is designed to be played over and over repeate ...

509 Normalized time is useful when synchronizing two or more animation clips that are not necessarily of the same absolute durat ...

510 11. Animation Systems As we saw above, playing a looping animation is like laying down an infi nite number of back-to-front ...

511 In order to map an animation clip onto a global time line, we need the fol- lowing pieces of information about the clip: it ...

512 11. Animation Systems time index t is usually taken to be zero. To advance the animations for- ward in time, we advance the ...

513 // more updates... UpdatePlayer(); // punch button hit – start punch // anim, and send event to NPC to // react // still mor ...

514 11. Animation Systems 11.4.4. A Simple Animation Data Format Typically, animation data is extracted from a Maya scene fi le ...

515 In C++, an animation clip can be represented in many diff erent ways. Here is one possibility: struct JointPose { ... }; // ...

516 11. Animation Systems imation authored for one of these skeletons should work on any of them. The only requirement is that t ...

517 11.4.6. Metachannels Many games permit additional “metachannels” of data to be defi ned for an animation. These channels can ...

518 11. Animation Systems fi eld of view (focal length) of the camera, and possibly other camera att ributes, can also be animat ...