Graphics Basic of Animation Graphics Lab Korea University

Graphics Basic of Animation 고려대학교 그래픽스 연구실 Graphics Lab @ Korea University

Overview CGVR n Animation의 기본원칙 n Animation이란? n Animation의 기본 원칙 n 움직임 만들기 n Animation Technique의 분류 제작 기법에 따른 분류 n 기타분류 n Graphics Lab @ Korea University

동화 (Inbetween Animation) CGVR Graphics Lab @ Korea University

Overview CGVR n Animation의 기본원칙 n Animation이란? n Animation의 기본 원칙 n 움직임 만들기 n Animation Technique의 분류 제작 기법에 따른 분류 n 기타분류 n Graphics Lab @ Korea University

제작 기법에 따른 분류 n CGVR Camera 2 D n 3 D n n Cameraless Direct Animation n CGA (Computer Graphic Animation) n Graphics Lab @ Korea University

제작 기법에 따른 분류 - Camera n 2 D n n n n CGVR Paper Animation Cell Animation Cut-out Animation Sand Animation Silhouette Animation Painting on Glass 3 D Graphics Lab @ Korea University

제작 기법에 따른 분류 - Camera CGVR 2 D n 3 D n Puppet Animation n Claymation n Pixilation n Graphics Lab @ Korea University

제작 기법에 따른 분류 Cameraless n CGVR Direct Animation Drawing on Film n Scratching on film n n CGA (Computer Graphic Animation) Graphics Lab @ Korea University

제작 기법에 따른 분류 Cameraless CGVR Direct Animation n CGA (Computer Graphic Animation) n 2 D Computer Animation n 3 D Computer Animation n Graphics Lab @ Korea University

기타분류 CGVR Abstract Animation n Experimental Animation n Limited Animation / Full Animation n 실사합성 Animation Full Animation Limited Animation Graphics Lab @ Korea University

Graphics Computer Animation 고려대학교 그래픽스 연구실 Graphics Lab @ Korea University

Computer Animation n What is Animation? n n CGVR Make objects change over time according to scripted actions What is Simulation? n Predict how objects change over time according to physical laws Graphics Lab @ Korea University

Outline n Principles of Animation n Keyframe Animation n Articulated Figures CGVR Graphics Lab @ Korea University

Principle of Traditional Animation – Disney – n n n CGVR Squash and Stretch Slow In and Out Anticipation Exaggeration Follow Through and Overlapping Action Timing Staging Straight Ahead Action and Pose-to-Pose Action Arcs Secondary Action Appeal Graphics Lab @ Korea University

Anticipation n CGVR 이전 동작으로 다음 동작을 예측 가능하도록 표 현 점프 착지 Graphics Lab @ Korea University

Computer Animation n CGVR Animation Pipeline n n n 3 D modeling Motion specification Motion simulation Shading, lighting, & rendering Postprocessing Graphics Lab @ Korea University

Outline n Principles of Animation n Keyframe Animation n Articulated Figures CGVR Graphics Lab @ Korea University

Keyframe Animation n CGVR Define Character Poses at Specific Time Steps Called “Keyframes” Graphics Lab @ Korea University

Keyframe Animation n CGVR Interpolate Variables Describing Keyframes to Determine Poses for Character in between Graphics Lab @ Korea University

Inbetweening n CGVR Linear Interpolation n Usually not enough continuity Graphics Lab @ Korea University

Inbetweening n CGVR Spline Interpolation n Maybe good enough Graphics Lab @ Korea University

Inbetweening n CGVR Spline Interpolation n Maybe good enough o May not follow physical laws Graphics Lab @ Korea University

Inbetweening n CGVR Inverse Kinematics or Dynamics Graphics Lab @ Korea University

Outline n Principles of Animation n Keyframe Animation n Articulated Figures CGVR Graphics Lab @ Korea University

Articulated Figures n CGVR Character Poses Described by Set of Rigid Bodies Connected by “Joints” Base Arm Hand Scene Graphics Lab @ Korea University

Articulated Figures n CGVR Well-Suited for Humanoid Characters Graphics Lab @ Korea University

Articulated Figures n CGVR Joints Provide Handles for Moving Articulated Figure Graphics Lab @ Korea University

Inbetweening n CGVR Compute Joint Angles between Keyframes n consider the length constancy Right Wrong Graphics Lab @ Korea University

Example: Walk Cycle n CGVR Articulated Figure: Hip Upper Leg (Hip Rotate) Upper Leg Hip Rotate Knee Lower Leg Ankle Foot Lower Leg (Knee Rotate) Hip Rotate + Knee Rotate Foot (Ankle Rotate) Graphics Lab @ Korea University

Example: Walk Cycle n CGVR Hip Joint Orientation: Graphics Lab @ Korea University

Example: Walk Cycle n CGVR Knee Joint Orientation: Graphics Lab @ Korea University

Example: Walk Cycle n CGVR Ankle Joint Orientation: Graphics Lab @ Korea University

Challenge of Animation n CGVR Temporal Aliasing n Motion blur Graphics Lab @ Korea University

Temporal Ailasing n CGVR Artifacts due to Limited Temporal Resolution Strobing n Flickering n Graphics Lab @ Korea University

Motion Blur n CGVR Composite Weighted Images of Adjacent Frames n Remove parts of signal under-sampled in time Graphics Lab @ Korea University

Summary n CGVR Animation Requires. . . n n n Modeling Scripting Inbetweening Lighting, shading Rendering Image processing Graphics Lab @ Korea University