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Graphite 2005. Texture for Volume Character Animation. Peiyi Shen and Philip Willis. Media Technology Research Centre Department of Computer Science University of Bath UK http://www.bath.ac.uk/media/. Texture for Volume Character Animation Introduction.
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Graphite 2005 Texture for Volume Character Animation Peiyi Shen and Philip Willis Media Technology Research Centre Department of Computer Science University of Bath UK http://www.bath.ac.uk/media/
Texture for Volume Character AnimationIntroduction • New challenges and applications in manipulating/animating/annotating volume datasets. STAR-EG2005 : Deforming and Animating Discretely Sampled Object Representations, State of the Art Report, Eurographics ‘05, Dublin, Ireland. Graphite 2005
Texture for Volume Character AnimationIntroduction • Volume Datasets - a collection of discrete samples - no geometrical / topological / semantic information -> new challenges in deformation / animation / annotation control Graphite 2005
Texture for Volume Character AnimationIntroduction • Mesh texturing is well-advanced • Problems of mesh models? Graphite 2005
Dawn:Curtis Beeson, Kevin Bjorke, Skin in the “Dawn” Demo, Computer Graphics, Vol. 38, No. 2, 2004, pp 14-19. • Cubic map of environment; Diffuse colour map / bump map for the front of the head; Vertex shader techniques. Graphite 2005
Skin(BSSRDF): Henrik W. Jensen, Stephen R. Marschner, Marc Levoy and Pat Hanrahan, A Practical Model for Subsurface Light Transport, SIGGRAPH 2001. Skin(Light-Diffusion): C. Donner, H. W. Jensen, Light Diffusion in Multi –Layered Translucent Materials, SIGGRAPH 2005. Graphite 2005
Spherical Matching:J. Starck, A. Hilton, Spherical Matching for Temporal Correspondence of Non-Rigid Surface, ICCV 2005. • Spherical parameterisation Graphite 2005
Mesh Models: Filling Holes in Complex Surface using Volumetric Diffusion [Ref1] An Out-of-core Algorithm for Isosurface Topology Simplification[Ref2] Graphite 2005
Volume Animation: STAR-EG2005 Graphite 2005
Texture for Volume Character AnimationMotivation • Our targets are: 1. To texture volume objects with realistic appearance. 2. To develop a method which is robust to topological artefacts 3. To use scalar-field based semantic constraints to assist texture mapping Graphite 2005
Texture for Volume Character AnimationFunctionality of our system • Plenoptic/cel texture + projective indexing + semantic control + scalar field based volume environments: VLIB (Andrew S. Winter: PhD thesis, Chapter 6, 2002, University of Wales, Swansea) • Plenoptic projection plus semantic constraints: effectively a one-to-one parameterisation texture mapping. Graphite 2005
Texture for Volume Character AnimationTexture Projection • Our system:the pipeline (Left: after the style of Andrew S. Winter, with acknowledgements) Graphite 2005
P(u,v) . . . . . . . . . . . . . . . . . . . Texture for Volume Character AnimationTexture Projection • Our system: Plenoptic/cel texture + projective indexing + … cel cylinder sphere box Texture primitives (Intermediate Template) (Ox,Oy,Oz) Graphite 2005
P(u,v) (Px,Py,Pz) . . . . P(x,y) . . . . . . . . Texture for Volume Character AnimationConstrained Rendering • Our system: … +semantic constrained volume rendering. (Ox,Oy,Oz) Graphite 2005
Texture for Volume Character AnimationSemantic Constraints • Semantic constraints: • spatial • temporal • iso-surfaces etc • Applications: • annotation • illustration • and some more… Graphite 2005
Texture for Volume Character AnimationSemantic Constraints • Intermediate template Graphite 2005
Texture for Volume Character AnimationSemantic Constraints • Texture projective mapping Graphite 2005
Texture for Volume Character AnimationSemantic Constraints • Volume visualisation Graphite 2005
Texture for Volume Character AnimationSemantic Constraints Example 1: Semantic constraint • Surface texture model: spherical • Internal texture model: procedural model • Semantic information: distance field • Volume rendering engine: DVR Graphite 2005
Texture for Volume Character AnimationTexture Appliactions Example 2: Multiple iso-surfaces • Volume rendering engine(DSR) will pick up multiple iso-surfaces. Graphite 2005
Texture for Volume Character Animation Texture Applications Example 3: Pseudo-solid texture • An effective one-to-one parameterisation texture mapping. • Figures (a) and (b): DVR • Figures(c) and (d): DSR Graphite 2005
Texture for Volume Character Animation Texture Applications Example 4: Semantic constraint (1) • spatial transfer / semantic layers / volumetric sculpturing Graphite 2005
Texture for Volume Character Animation Texture Applications Example 5: Semantic constraint (2) • CVG operations / scalar fields functions – splitting Graphite 2005
Texture for Volume Character Animation Texture Applications Example 6: Semantic constraint (3) • Enhanced volume rendering engine Graphite 2005
Texture for Volume Character Animation Texture Applications Example 7: Semantic constraints(4) Animation • Enhanced volume rendering engine: Animation apps. Graphite 2005
Texture for Volume Character AnimationConclusions • System features: • Volume Rendering Control • 2D/2.5D/3D texture models • Semantic constrained projective indexing: a practical “one-to-one” texture mapping model. • No mesh models, goes directly to volume datasets. Graphite 2005
Texture for Volume Character Animation Acknowledgements • UK EPSRC funding the project • Project partners: • University of Bath, UK • Professor Min Chen, Dr Mark Jones, University of Wales, Swansea, UK • Professor Deborah Silver The State University New Jersey, Rutgers, USA. • Special thanks to Dr Andrew S. Winter for supporting VLIB. • Ref:Volume Animation Forum http://www.cs.bath.ac.uk/van Graphite 2005
Texture for Volume Character Animation Acknowledgements Thank You Graphite 2005
Texture for Volume Character AnimationRefs. [Ref1] J. Davis, S.R. Marschner, M. Garr, M. Levoy, Filling Holes in Complex Surface using Volumetric Diffusion, Proc. 1st Int. Sym. On 3D Data Processing, Visualization, Transmission. Padua, Italy, June 19-21, 2002 [Ref2] Z. Wood, H. Hoppe, M. Desbrun, P. Schroder, An Out-of-core Algorithm for Isosurface Topology Simplification, ACM Tran. On Graphics, Vol.23, No.2, 2004, pp 190-208 Graphite 2005