Volume animation using the skeleton tree
Nikhil Gagvani, D. Kenchammana-Hosekote, D. Silver · 1998
b this paper, w describe a technique to hate volumes using a volumetric skdeton.The skdeton is computed born the actual volum~b=ed on a reversible thinning procedure u~ing the distance transfomPolygons are never computed, and the entire proc-remains in the volume domain.The skeletal points =e connected and arranged in a 'skeletontree", which can be used for artictiation in an animation program.The ti volume object is regrown Corn the tr~ fomed skdetti points.Since the skdeton is an intuitive mechanism for animation, the animator deforms the skeleton and causes corre~onding deformations in the volume object.The volumetric skdeton can *O be used for volume morphing, automatic path navigation, volume smoothing and compresGon/decimation.Kepor&I'olurne Graphics, Skdeton, Animation, Volume Deformation. introductionThe Sdd of volume graphics is gaining momentum as volumetric dat=ets become more widespread and the computational power to render these datasets becomes a~dable.The god of volume graphics is to replace the tradition polygonbased graphics piphe with a volumebased pip~e.This includes volume mod~g, animation and rendering.Took for deforming and &at-mg volumetric objects have ap pEcations in scientific and medid visu&ation and, Iatdy, in comrnerci~animation where computational simdations and volumetric mod& are used for generating rhtic effects.However, because the volumes are large and rendering is non-intsractivq maniptiating volumetic objects is Mctit -and non-intuiti~e k stmdard grapfiw processing, artidated skdetons are often used for dtiormation -d tiation [21].b this paper, we propose using vohnn~based skdetons to control animation and deformation in volumetric objects.Skdetd VOX* me determined directly tiom the volume objects.The vox-& =e arranged in a skeleton-tr= which m be manipdated me st~dmd arti~ated skdetona, i.a, deformed ad animated.The volume objects a then be regenerated from the skdeton-tree for rendering.There are three steps in skdeton bz~ed animation computation of the sk~eton and the skdeton tree (skdetotiation), animation of the skdeton (deformation) and, fi~y, regeneration of the object from the tiated skdeton (reconstruction).The skdeton-tiee is intuitive because it suggests the shape of the object.A key feature of the skeleton-tree is that it can be imported into tradition animation environments and tiated, dewing animators to use their existing fi-br~of motion control took, me motion capture, parametric key tie animation, constraint-based inlers-wmatics