Volume 38 (2019)

Permanent URI for this community

https://diglib.eg.org/handle/10.2312/2632736

Browse

Browsing Volume 38 (2019) by Subject "and systems"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Dense Point-to-Point Correspondences Between Genus-Zero Shapes
    (The Eurographics Association and John Wiley & Sons Ltd., 2019) Lee, Sing Chun; Kazhdan, Misha; Bommes, David and Huang, Hui
    We describe a novel approach that addresses the problem of establishing correspondences between non-rigidly deformed shapes by performing the registration over the unit sphere. In a pre-processing step, each shape is conformally parametrized over the sphere, centered to remove Möbius inversion ambiguity, and authalically evolved to expand regions that are excessively compressed by the conformal parametrization. Then, for each pair of shapes, we perform fast SO(3) correlation to find the optimal rotational alignment and refine the registration using optical flow. We evaluate our approach on the TOSCA dataset, demonstrating that our approach compares favorably to state-of-the-art methods.
  • Thumbnail Image
    Item
    Single-View Modeling of Layered Origami with Plausible Outer Shape
    (The Eurographics Association and John Wiley & Sons Ltd., 2019) Kato, Yuya; Tanaka, Shinichi; Kanamori, Yoshihiro; Mitani, Jun; Lee, Jehee and Theobalt, Christian and Wetzstein, Gordon
    Modeling 3D origami pieces using conventional software is laborious due to the geometric constraints imposed by the complicated layered structure. Targeting origami models used in visual content such as CG illustrations and movies, we propose an interactive system that dramatically simplifies the modeling of 3D origami pieces with plausible outer shapes, while omitting accurate inner structures. By focusing on flat origami models with a front-and-back symmetry commonly found in traditional artworks, our system realizes easy and quick modeling via single-view interface; given a reference image of the target origami piece, the user draws polygons of planar faces onto the image, and assigns annotations indicating the types of folding operations. Our system automatically rectifies the manually-specified polygons, infers the folded structures that should yield the user-specified polygons with reference to the depth order of layered polygons, and generates a plausible 3D model while accounting for gaps between layers. Our system is versatile enough for modeling pseudo-origami models that are not realizable by folding a single sheet of paper. Our user study demonstrates that even novice users without the specialized knowledge and experience on origami and 3D modeling can create plausible origami models quickly.
  • Thumbnail Image
    Item
    String-Based Synthesis of Structured Shapes
    (The Eurographics Association and John Wiley & Sons Ltd., 2019) Kalojanov, Javor; Lim, Isaak; Mitra, Niloy; Kobbelt, Leif; Alliez, Pierre and Pellacini, Fabio
    We propose a novel method to synthesize geometric models from a given class of context-aware structured shapes such as buildings and other man-made objects. The central idea is to leverage powerful machine learning methods from the area of natural language processing for this task. To this end, we propose a technique that maps shapes to strings and vice versa, through an intermediate shape graph representation. We then convert procedurally generated shape repositories into text databases that, in turn, can be used to train a variational autoencoder. The autoencoder enables higher level shape manipulation and synthesis like, for example, interpolation and sampling via its continuous latent space. We provide project code and pre-trained models.