Abstraction of man-made shapes

Abstract

Figure 1: Given three-dimensional models of man-made objects, often containing multiple self-intersecting components, we extract characteristic curve networks along with auxiliary normal information providing a compact vector representation of the main model features and use those to generate 3D abstractions capturing the essence of the inputs. AbstractMan-made objects are ubiquitous in the real world and in virtual environments. While such objects can be very detailed, capturing every small feature, they are often identified and characterized by a small set of defining curves. Compact, abstracted shape descriptions based on such curves are often visually more appealing than the original models, which can appear to be visually cluttered. We introduce a novel algorithm for abstracting three-dimensional geometric models using characteristic curves or contours as building blocks for the abstraction. Our method robustly handles models with poor connectivity, including the extreme cases of polygon soups, common in models of man-made objects taken from online repositories. In our algorithm, we use a two-step procedure that first approximates the input model using a manifold, closed envelope surface and then extracts from it a hierarchical abstraction curve network along with suitable normal information. The constructed curve networks form a compact, yet powerful, representation for the input shapes, retaining their key shape characteristics while discarding minor details and irregularities.

Interactive Inverse 3D Modeling

“…The former two types tend to be faster to evaluate and more precise, but more dependent on a carefully controlled patch network topology for good results, which renders them intimidating for novices compared to variational patches, which, however, are computationally more expensive. Smooth surface patch fitting can be used in several different fitting contexts: It can match an existing surface topologically, it can abstract a surface by matching a smooth surface envelope to the surface [22], or it can also be used for modeling offset surfaces and for blending between surface portions extracted by other modules.…”

Intuitive Design Exploration of Constrained Meshes

“…In freeform architectural design, a few curves may dominate the aesthetic characteristic of the shapes (see e.g., [Mehra et al 2009]). Hence, designers often take great care to prescribe such curves and expect the rest of the shape to blend in.…”

Illustrating the disassembly of 3D models

“…Recently, understanding the higher-level representations of 3D models has received considerable interest (see survey [11]), including symmetry detection [12,13,14], upright orientation inference [15] and shape abstractions [16]. Benefitting from these techniques, a wide spectrum of applications are spawned, such as shape manipulation [17,18,19], shape synthesis [20], motion analysis [21,22,23,24] and computational furniture design [25].…”