Campos, JordiPuig, AnnaTost, DaniPere Brunet and Nuno Correia and Gladimir Baranoski2014-01-312014-01-3120063-905673-60-6http://dx.doi.org/10.2312/LocalChapterEvents/siacg/siacg06/079-087We propose a hierarchical representation of volume data sets based on a user-given definition of features. The model is general and it can be used for various types of feature definitions such as rendering queries, topological skeletons and property-based classification. We use this model to interactively select features of the volume and to render them providing focus+context information. In addition, our model provides a mechanism to index directly the feature voxels, therefore it considerably speeds up rendering.Categories and Subject Descriptors (according to ACM CCS): I.3.3 [Computer Graphics]: Picture/Image generation- Display algorithms; I.3.6 [Computer Graphics]: Methodology and techniques - Graphics data structures and data types H.5.2 [Information interfaces and presentation]: User interfaces- Theory and methods